The Ucayali-Ene Basin Report, 2002.pdf

UCAYALI & ENE BASINS Technical Report As part of The Hydrocarbon Potential of the Southern Sub-Andean Basins Project Ucayali, Ene and Madre de Dios Basins by

PARSEP Proyecto de Asistencia para la Reglamentación del Sector Energético del Perú TEKNICA

PERUPETRO S.A.

Gary Wine (Project Leader) Bob Parker (Senior Geophysicist)

Elmer Martínez (Senior Geophysicist/Perupetro Coordinator) Justo Fernandez (Senior Geologist) Ysabel Calderón (Geologist) Carlos Galdos (Geophysicist)

December 2002

TABLE OF CONTENTS TABLE OF CONTENTS ............................................................................................0 FIGURES......................................................................................................................3 TABLES........................................................................................................................5 ENCLOSURES ............................................................................................................5 APPENDIX...................................................................................................................6 EXECUTIVE SUMMARY .........................................................................................8 1.0 INTRODUCTION...............................................................................................10 2.0 SCOPE OF PROJECT .......................................................................................12 3.0 PREVIOUS WORK IN THE STUDY AREA ..................................................15 4.0 GEOLOGY OF THE UCAYALI/ENE AREA ................................................17 4.1 GENERAL BASIN DESRIPTION...................................................................17 4.2 REGIONAL GEOLOGY..................................................................................18 4.2.1 Pre-Andean System ....................................................................................18 4.2.2 Andean System ...........................................................................................22 4.3 GEOLOGY OF THE UCYALI/ENE PROJECT AREA..................................26 4.3.1 Project Overview .......................................................................................26 4.3.2 Stratigraphy of the Ucayali/Ene Area........................................................28 4.3.2.1 Basement.............................................................................................29 4.3.2.2 Ordovician...........................................................................................29 4.3.2.3 Silurian................................................................................................29 4.3.2.4 Devonian - Cabanillas Group.............................................................29 4.3.2.6 Late Carboniferous to Early Permian - Tarma/Copacabana Group...31 4.3.2.7 Late Permian .......................................................................................36 Shinai Member.............................................................................................39 Red Bed Group/Mainique ............................................................................39 Permian/Cretaceous Basin Evolution – Camisea Area................................41 4.3.2.8 Triassic to Jurassic ..............................................................................41 Mitu..............................................................................................................41 Pucará Group ...............................................................................................42 Evaporites (Salt)...........................................................................................43 Sarayaquillo .................................................................................................44 4.3.2.9 Cretaceous...........................................................................................45 Cushabatay...................................................................................................46 Agua Caliente...............................................................................................48 Chonta ..........................................................................................................48 Vivian Formation .........................................................................................49 4.3.2.10 Tertiary..............................................................................................49 4.3.3 Structural Analysis of the Ucayali/Ene Area ..............................................50 4.3.3.1 Devonian Faults ..................................................................................51 4.3.3.2 Late Paleozoic Faults/Structures.........................................................51 4.3.3.3 Late Andean Foreland Faults/Structures.............................................52 4.3.3.4 Cushabatay High.................................................................................52

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4.3.3.5 Contaya Arch ......................................................................................54 4.3.3.6 Shira Mountains ..................................................................................54 4.3.3.7 Fold and thrust belt of the Ene and western Ucayali Basin ................55 North and Central Areas ..............................................................................55 Oxapampa and Ene Basin Areas..................................................................55 Camisea Area ...............................................................................................61 4.3.3.8 Structural Profiles ...............................................................................64 Section A (Enclosure 3a) .............................................................................64 Section B (Enclosure 3b) .............................................................................65 Section C (Enclosure 3c) .............................................................................65 Section D (Enclosure 3d) .............................................................................66 Section E (Enclosure 3e)..............................................................................66 Section F (Enclosure 3f) ..............................................................................66 5.0 GEOPHYSICS ....................................................................................................68 5.1 INTRODUCTION ............................................................................................68 5.2 DATA QUALITY.............................................................................................69 5.3 WELL TIES ......................................................................................................69 5.3.1 Ucayali North.............................................................................................69 5.3.2 Ucayalii South............................................................................................69 5.4 HORIZONS INTERPRETED ..........................................................................70 5.5 MAPS PLOTTED.............................................................................................70 5.5.1 General Comments.....................................................................................71 5.5.2 Time Structure Maps – Ucayali North.......................................................72 5.5.2.1 Pozo (Figure 30, Enclosure 4a)...........................................................72 5.5.2.2 Base Cretaceous (Figure 31, Enclosure 4b)........................................74 5.5.2.3 Copacabana (Figure 32, Enclosure 4c) ................................................74 5.5.2.4 Contaya (Figure 33, Enclosure 4d) .....................................................74 5.5.3 Isochron Maps – Ucayali North ................................................................74 5.5.3.1 Pozo to Base Cretaceous (Figure 34, Enclosure 4e). ..........................74 5.5.3.2 Base Cretaceous – Contaya Isochron (Figure 35, Enclosure 4f) ........74 5.5.4 Time Structures Maps – Ucayali South .....................................................75 5.5.4.1 Upper Cretaceous (Figure 36, Enclosure 5a)......................................75 5.5.4.2 Base Cretaceous (Figure 37, Enclosure 5b)........................................75 5.5.4.3 Tarma (Figure 38, Enclosure 5c) .........................................................76 5.5.4.4 Top Devonian (Figure 39, Enclosure 5d) ............................................76 5.5.4.5 Basement (Figure 40, Enclosure 5e)...................................................78 5.5.5 Isochron Maps – Ucayali South.................................................................79 5.5.5.1 Cretaceous Isochron (Upper to Base) (Figure 41, Enclosure 5f).........79 5.5.5.2 Upper Cretaceous – Tarma Isochron (Figure 42, Enclosure 5g) ........79 5.5.5.3 Lower Paleozoic (Devonian-Basement) Isochron (Figure 43, Enclosure 5h) ...................................................................................................79 5.5.6 Cretaceous Channel Play – Ucayali South................................................81 5.5.7 Future work to be done ..............................................................................82 6.0 WELL SUMMARY ............................................................................................83 7.0 PETROLEUM GEOLOGY ...............................................................................84 7.1 GEOCHEMISTRY ...........................................................................................84 7.1.1 General ......................................................................................................84 7.1.2 Source Rocks..............................................................................................84 2

7.2 RESERVOIRS/SEALS.....................................................................................85 7.3 PROSPECTS/LEADS.......................................................................................87 7.3.1 Structural Prospects...................................................................................87 7.3.1.1 Rashaya Norte.....................................................................................87 7.3.1.2 Rio Caco Sur .......................................................................................88 7.3.2 Stratigraphic Leads....................................................................................89 7.3.2.1 Cushabatay South Pucará Lead (CSPL) .............................................89 7.3.2.2 Mashansha Channel ............................................................................91 8.0 CONCLUSIONS .................................................................................................92 9.0 SELECTED REFERENCES .............................................................................94

FIGURES Figure 1: Area of investigation of the PARSEP Group for the Southern Sub-Andean Basins of Peru. ......................................................................................................................10 Figure 2: Location of the Seismic and Wells utilized in the study of the Ucayali Basin .............13 Figure 3: Location of Madre de Dios Basin area and the available seismic data (in red) ..........14 Figure 4: Stratigraphic Columns for the Sub-Andean Basins of Peru, highlighting the Ucayali Basin......................................................................................................................19 Figure 5: Composite seismic line through the South-Central portion of the Ucayali Basin showing a) the magnitude of the Devonian-Ordovician (?) rift Basins, b) the onlap relationship of the Carboniferous Ambo onto the Eohercynian Unconformity, and c) the truncation of the Paleozoic sequences beneath the Nevadan Unconformity at the Base of Cretaceous..............................................................................................................20 Figure 6: Seismic Line in the south central Ucayali Basin showing a significant amount of erosion on the pre Ambo sequences (Devonian) beneath the Eohercynian Unconformity (dk. blue reflector). ........................................................................................................21 Figure 7: Seismic line OR-95-08 in the northern Contaya Arch area showing the evolution of a Late Permian to early Mesozoic extensional basin through the use of different datums (flattenings) (after PARSEP, 2002) ............................................................................24 Figure 8: (After Tankard, 2001) Late Triassic – Middle Jurassic paleogeography. The locus of sedimentation was the extensional tract between the Contaya (csz) and Shionayacu (ssz) shear zones. Isopachs show that the stratigraphy terminated abruptly against NE-striking faults, and for this reason they are described as basin sidewall faults. psz, Pucalpa shear zone; sol, Solimoes Basin. .........................................................................................25 Figure 9: Isochron map of the Ambo Group in the southern Ucayali Basin ............................30 Figure 10: An example of a 50 to 60 meter anhydrite unit within the upper Copacabana section that has been repeated by a thrust fault. The log on the right is the hanging wall section and the one on the right, the footwall section. Note: The repeated section has been removed in the Huaya 3X well in the stratigraphic stratigraphic cross-sections 1 and 2....32 Figure 11: West to East seismic line through the Panguana well showing a) how the Copacabana has been erosionally reduced beneath the Base Cretaceous unconformity and b) The anomalously thick section of pre-Ambo sediments intersected in the Panguana well. The Basement pick is very interpretive and base largely on the results of the Panguana 1X well.

..............................................................................................................................32 Figure 12: Distribution of the Ene Formation as mapped seismically in the Ucayali Basin. The seismic line shown in Figure 14 is located on this map ..................................................34 Figure 13: NW/SE stratigraphic cross-section flattened in the Upper Permian unconformity shows the late Permian post Tarma/Copacabana Group stratigraphy. Orellana 1X is in the SE Marañon Basin. ..................................................................................................35

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Figure 14: Seismic line CP739801 (located on Figure 12) through a thick preserved Permian section in the Northern Ucayali Basin. In an alternative interpretation, the Top Copacabana was picked at an alternative reflector, the pink mk below the Grn Sdst. If this surface were a significant unconformity, as it would appear from this seismic interpretation, this horizon would most likely represent the Devonian unconformity so readily visible in the southern Ucayali Basin, thereby supporting the interpretation presented above. ......................................................................................................36 Figure 15: Stratigraphic cross-section flattened on Base Cretaceous shows detailed late Permian stratigraphy. Note excellent log correlation in Shinai, and two 10 m. thick anhydrite beds in the Middle Mudstone Formation and anhydrite beds in the Noi Sandstone Patsite Member.

..............................................................................................................................37 Figure 16: Evolution of the post-Copacabana Permian and Cretaceous sequences in the Camisea area through flattenings in Noi, Shinai, Lower Nia, Mid Mudstone or Base-Cretaceous, Agua Caliente, Chonta and Vivian Formations ...........................................................40 Figure 17: Isochron Map of the salt ‘swells’ in the western Ucayali Basin. Cold colors represent thins and hot colors represent thicks. .........................................................................44 Figure 18: Seismic line across the Aguaytia structure showing the presence of salt (?) within an Andean inverted, early Mesozoic-aged graben. ...........................................................45 Figure 19: Isopach of the Cretaceous in the Ucayali Basin from well control with the significant pinchout (onlap) edges of the Cretaceous sequences highlighted. Note the dramatic thinning of the Cretaceous from northwest to southeast. ..............................................47 Figure 20: Seismic Profile 3 from PARSEP (2002a), extending from the Huallaga Basin (left) to the Ucayali Basin (right) showing the interpreted inverted nature of the Cushabatay High, late Permian-early Triassic half graben. .....................................................................53 Figure 21: Map of the Shira Mountains (Pajonal High), Pachitea Basin and the Oxapamapa and Ene Basin Fold and thrust Belt showing the major tectonic features (after Elf, 1996a). Elf has divided the Ene Basin into three regions, the northern, central and southern Ene Basins

..............................................................................................................................56 Figure 22: Structural profile through the central Ene Basin modeled from the interpretation of seismic line Elf96-09 (after Elf, 1996c). In this region, the principal detachment surface and zone of multiple imbrications, is interpreted to be within the Cabanillas Formation. The Elf interpretation has the western margin of the Shira Mountains as an ‘old’ high controlled by a series of down to the west normal faults of substantial displacement that acted as a buttress to eastern the advancing thrust front. .............................................57 Figure 23: Magnetic Map (reduced to pole total field) of the Ene Basin showing the contrast in magnetic characteristics been the northern Ene Basin and the Central and Southern Basins across the Tambo Fault zone. ....................................................................................58 Figure 24: Evolution of the of the Tambo Fault zone (After Elf, 1996a) – Two alternative explanations with the inactive paleogeographic limit scenario being favored. ..................59 Figure 25: Location of present day seismicity in the Ene Basin and surrounding area (from Elf, 1996c). ...................................................................................................................60 Figure 26: Late Cretaceous – Tertiary paleogeography in which the locus of subsidence and deposition was the Marañon – Oriente basin area. co, Contaya high; cob, boundary between continental and oceanic crust; csz, Contaya shear zone; cu, Cushabatay high; Cv, Cordillera Vilcabamba range and shear zone; fc, Fitzcarrald anticline; Hu, Huallaga basin; j-n, Jambeli-Naranjal shear zone; MdD, Madre de Dios range; Pr, Progreso basin; s, oil seeps; Sa, Santiago basin; Ta, Talara basin; Tr, Trujillo basin; Uc, Ucayali basin; vu, Vuana fault. (after Tankard 2002). ............................................................................62 Figure 27: Series of three seismic lines aligned on the San Martin Anticline showing the northeast propogation of the thrust front into the southern Ucayali Basin from west to east.

..............................................................................................................................63 Figure 28: Radar image of western regions of the Ucayali Basin crossed by Section C. Section B is located parallel to D but just off the map to the north. ..............................................65 Figure 29: Seismic SHL-UBA-22 showing the San Martin structure on the South end of the line, and an un-drilled structure just over half way along the line. The two red horizons mark the Cretaceous interval. The blue pick is Top Devonian, the cyan is Basement. ...............72 Figure 30: Pozo Time Structure, Ucayali North. ..................................................................73

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Figure 31: Base Cretaceous Time Structure, Ucayali North. .................................................73 Figure 32: Copacabana Time Structure, Ucayali North. .......................................................73 Figure 33: Contaya Time Structure, Ucayali North..............................................................73 Figure 34: Pozo-Base Cretaceous Isochron (Ucayali North)..................................................73 Figure 35: Base Cretaceous – Contaya Isochron (Ucayali North) ...........................................73 Figure 36: Upper Cretaceous Time Structure, Ucayali South. ..............................................75 Figure 37: Base Cretaceous Structure Time, Ucayali South..................................................76 Figure 38: Tarma Time Structure, Ucayali South. .............................................................77 Figure 39: Top Devonian Time Structure, Ucayali South. ....................................................77 Figure 40: Basement Time Structure, Ucayali South. ..........................................................78 Figure 41: Cretaceous Isochron, Ucayali South. ..................................................................79 Figure 42: Upper Cretaceous – Tarma Isochron, Ucayali South. ...........................................80 Figure 43: Lower Paleozoic Isochron, Ucayali South. ...........................................................80 Figure 44: Seismic Lines rep35-124, 126 and 128 (top to bottom), over the channel feature discussed in the text. Note the high amplitude event in the middle of the channel on line 126.

..............................................................................................................................81 Figure 45: Cretaceous channel Isochron, Ucayali South. ......................................................82 Figure 46: TWT Map on Base of Cretaceous along the Runuya/Rio Caco/Tamaya anticline showing the undrilled structure remaining at Rio Caco Sur ..........................................88 Figure 47: Seismic line across the Rio Caco structure highlighted on the preceding Figure. .....89 Figure 48: Location of Seismic Line CP739801 ...................................................................89 Figure 49: Seismic line CP739801 through the CSPL lead, a Pucará play where high energy carbonates are expected to have been deposited over a Copacabana erosional high. The upper section is a time section, the middle section is flattened on the Base Cretaceous and the bottom section is flattened on the Pucará. .............................................................90

TABLES Table 1: Seismic surveys used in the Ucayali study .............................................................68 Table 2: Wells used for synthetic seismogram ties (Ucayali South). ........................................69

ENCLOSURES Only in Hardcopy (in digital to request) 1.

2.

3.

Ucayali Basin Location Maps a. Location map of blocks, wells, and seismic b. Location map of cross-sections, wells, and seismic c. Location map of geological profiles, Enclosures 2(a to c) wells, and seismic Geological Maps of the Ucayali to Madre de Dios Basins with wells and seismic a. Northern Ucayali Basin (southern Marañon Basin, Huallaga Basin, Contaya Arch) b. Central Ucayali Basin (Oxapampa, northern Shira Mountains, La Colpa) c. Southern Ucayali and Ene Basins (southern Shira Mountains, Camisea) d. Northern Madre de Dios Basin (Karene, Cariyacu, Brazilian and Bolivian Borders) e. Southern Madre de Dios Basin (fold belt, Candamo 1X) Geological Profiles

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a.

4.

5.

Structural Section A-A' from SW to NE (Fold thrust belt, SE Cushabatay High, Santa Clara, Orellana) b. Structural Section B-B' from SWW to NEE (Fold thrust belt, Pisqui area, Cashiboya south) c. Structural Section C-C' from W to E (Fold thrust belt, Aguaytia, Moa Divisor) d. Structural Section D-D' from W to E (Fold thrust belt, Chio, Agua Caliente, East Tamaya) e. Structural Section E-E' from W to E (Oxapampa Area, Shira mountains) f. Structural Section F-F’ from SSW to NNE (Camisea, Panguana) Northern Ucayali Basin Seismic Maps a. TWT time structure Map – Pozo b. TWT time structure Map – Base Cretaceous c. TWT time structure Map – Cabanillas d. TWT time structure Map – Contaya e. Isochron – Pozo to Base Cretaceous f. Isochron – Base Cretaceous to Contaya Southern Ucayali Basin Seismic Maps a. TWT time structure Map – Upper Cretaceous b. TWT time structure Map – Base Cretaceous c. TWT time structure Map – Tarma d. TWT time structure Map – Top Devonian e. TWT time structure Map – Basement f. Isochron – Cretaceous g. Isochron – Upper Cretaceous to Tarma h. Isochron – Top Devonian to Basement

Digital (to request) 6. 7.

Ucayali Basin SEGY Data on Exabyte Tape CD’s containing a. Report b. Appendices and Enclosures

APPENDIX Hardcopy 1. 2.

3.

Wells drilled in the Ucayali Basin and their status Cross –sections across the Ucayali Basin a. Section 1: Orellana to Cashiboya Sur b. Section 2: Orellana to Panguana c. Section 3: Pisqui to Chonta d. Section 4: Coninca to San Martin e. Section 5: Pisqui to Mina San Vicente Area f. Section 6: Chio to Cashiboya Sur g. Section 7: Chio to Shahuinto h. Section 8: Mina San Vicente Area to Shahuinto i. Section 9: Camisea – Pongo Mainique to Panguana j. Section 10: Shahuinto to San Martin k. Location Map of Stratigraphic Cross-Sections Graphical presentation of wells drilled between 1990 and 2002 in the Ucayali Basin and the Camisea Discovery Wells a. Agua Caliente 31X b. Cachiyacu 1X c. Chio 1X d. Insaya 1X e. Mashansha 1X f. Pagoreni 1X g. Panguana 1X h. Rashaya Sur 1X

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i. j. k. l.

San Alejandro 1X Shahuinto 1X Camisea - Cashiriari 1X Camisea - San Martin 1X

Digital (CD - Enclosure 7b) 4. 5. 6. 7. 8. 9.

Listing of PARSEP Seismic Lines in SEGY – Excel Spreadsheet Access Well Database of Ucayali New Field Wildcats (NFW) – Access DB Composite Well Logs LAS Files of Ucayali NFW Northern Ucayali Seismic Interpretation – ASCII Data a. Horizon File b. Fault File Southern Ucayali Seismic Interpretation – ASCII Data a. Horizon File b. Fault File Ucayali Basin SEGY Seismic Navigational Data

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EXECUTIVE SUMMARY Project Description The Ucayali/Ene Basin Report is another in a series of reports generated by PARSEP (Projecto de Asistencia para La Reglamentacion del Sector Energetico del Peru), on the hydrocarbon potential of the Sub-Andean basins of Peru. The methodology is similar to the Maranon and other basinal reports already generated. The data, both well and seismic (from the archives of PeruPetro), was generated in digital format so that the work could be done on computer workstations for speed and efficiency. Geology The Ucayali Basin is one of the sub-Andean Basins of Peru with a prospective area of 105,000 km2 and some 5,000m of sedimentary infill. The Basin borders on the Brazilian Shield to the east and extends 650 km in length south from the Marañon Basin to the Madre de Dios Basin and 250 km in width east from the Fold Thrust Belt to beyond the Brazilian border. In the context of this study, the Ene Basin is considered to be simply a continuation of the thin-skinned deformation front which extends south from the Huallaga Basin and through the Oxapampa wells located directly north of the Ene Basin as it is currently defined. The Ucayali Basin includes thick sedimentary stratigraphic sequences that extend far beyond the present Ucayali Basin and merge with the greater Marañon and the Acre and Solimoes basins in Brazil and eventually pinch out onto the Brazilian and Guiana Shields. The geological evolution of the greater Ucayali Basin area is controlled by two regional tectonic systems recognized in the sub-Andean basins of Peru. The first, the pre-Andean System, encompasses three cycles of Ordovician, Devonian and Permo-Carboniferous ages overlying the Precambrian basement of the Guyana and Brazilian Shields. The second, the Andean System, was initiated with the beginning of subduction along the western margin of Peru. It encompasses several megastratigraphic sequences and numerous minor sedimentary cycles, ranging from Late Permian to the Present. The dominant structural form of the Basin is major basement-involved thrusting which in many cases is the result of reactivated Paleozoic normal faults, and along its western margin, it is one of detached thrusts along almost its entirety. The western thrust front can be divided into three segments; the northern Ucayali FTB, the Oxapampa/Ene FTB and the Camisea FTB. The first two are separated by a lateral ramp and the later two are divided by the Shira Mountains. At present, three oilfields (Agua Caliente, Maquia and Pacaya) and five gascondensate fields (Aguaytia, San Martin, Cashiriari, Pagoreni and Mipaya) have been discovered in the Ucayali Basin. Maquia and Agua Caliente fields are currently the only producing oil fields, with the Pacaya Field being shut-in. Of the four gas condensate fields only Aguaytia is on production although the Camisea fields are under development and expected to be on production in the near future. The main

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reservoirs in the Basin are Cretaceous continental and marine sandstones with subordinate Upper Permian lacustrine, eolian and restricted marine sandstones. Wells Standardized composite well logs were generated for all the wells with available logs, and used to create a grid of cross-sections over the Basin. Approximately 40 wells were used in this study. Seismic As the well coverage in this basin is relatively sparse, the study is largely driven by seismic interpretation. This meant that the seismic data had to be loaded onto workstations for interpretation. Upon doing so it was found that several of the data sets did not tie properly. A considerable amount of time was lost in analyzing the errors and correcting the positional data to a standard datum – in this case, a UTM WGS-84 grid – and re-loading all the data. The seismic data was interpreted in two sections, designated Ucayali North and Ucayali South. The northern half was interpreted and mapped using Kernel Technology’s WinPics software on a PC platform; Ucayali South was interpreted and mapped on Schlumberger GeoQuest IESX software on a Sun Platform running in a UNIX environment. Interpretation The interpretation for the Ucayali project is supported by ten regional stratigraphic cross sections, designed to include almost all the wells in the Basin and six regional structural profiles. A total of ten two-way time structure maps were generated from the geophysical interpretation, along with six Isochron maps. An attempt has been made within the time framework of this study to produce a standardized stratigraphic column for the Ucayali Basin. This attempt has been partially successful, but there are still a number of unanswered questions that may form the basis of further study. The Ucayali/Ene Basin Study was intended to be a regional work, integrating as much data as possible within the Basin to investigate whether new exploration concepts, etc., could be defined. It was not intended to be an exploration exercise where the ultimate goal is in defining drillable prospects. Ultimately however, in a study such as this, certain prospects and leads do emerge. During the process of this evaluation two structural prospects and two stratigraphic leads were defined. It should be noted that there are numerous other structural leads in the Basin and these have been well documented in other Perupetro reports. The two stratigraphic leads, the Mashansha Channel Play and the Cushabatay South Pucará play, on the other hand are new concepts and believed to be only partially representative of what can be found when a concentrated effort in exploring for stratigraphic traps is applied.

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1.0 INTRODUCTION The Southern Sub-Andean Basin Project is the last of several by the PARSEP Group on the evaluation of the hydrocarbon potential of the Sub-Andean Basins of Peru. PARSEP is an acronym for “Proyecto de Asistencia para La Reglamentación del Sector Energético del Perú” and is a joint venture between the governments of Peru and Canada. The parties comprising PARSEP are: the Canadian International Development Agency (CIDA), the Canadian Petroleum Institute (CPI), Teknica Overseas Ltd. (TOL), and PERUPETRO. The technical work on this project is being done by personal from TOL and PERUPETRO. The basins evaluated previously were in Northeastern Peru, and included the Huallaga, Santiago and Marañon Basins.

Southern Sub-Andean Basins of Peru Study Area

Figure 1: Area of investigation of the PARSEP Group for the Southern Sub-Andean Basins of Peru.

This phase of the project was originally proposed to complete three independent studies on the Ucayali, Ene and Madre de Dios Basins. The Ene Basin after reviewing the regional geology, however is considered for all intensive purposes to be part of the Ucayali Basin by the PARSEP Group and consequently it’s evaluation has been incorporated within contents of this study. There was a debate whether to include the Madre de Dios Basin as well but it was ultimately decided to do a separate report on this Basin. This restructuring has resulted in this PARSEP study being called the “Ucayali/Ene Basin Technical Report”

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Unlike the previous PARSEP studies, the one on the Ucayali/Ene Basin is not as complete an evaluation as the one done for the Marañon Basin (PARSEP 2002) in that certain sections such as geochemistry, basin modeling and prospective areas have been reduced or omitted. The emphasis of the last year’s work has been on data gathering, quality controlling and correcting the data, and in defining the stratigraphic and structural framework of the Basin. Despite receiving critical data sets needed for the interpretation within the last month of the study to complete this analysis, most of these objectives have been met. This study represents an excellent staging point from which a more detailed examination of the Basin can be continued. All the SEGY data utilized in this project was supplied by Perupetro and was interpreted primarily utilizing a Schlumberger GeoQuest UNIX based seismic interpretation software and with Kernel Technology’s WinPICs PC based seismic interpretation software. The seismic data was tied (bulk-shifted, phase rotated and amplitude-tied) utilizing Kernel Technology’s SMAC software. On the geological side, Geographixs and DigiRule software were used extensively for mapping, well log preparation and cross-section construction. Microsoft Access was utilized to design a standardized, exportable well database in the same format carried forward from the previous PARSEP Studies. The PARSEP Team would like to thank Perupetro, CPI and Teknica for their technical and logistical support on this project and CIDA for making this project a possibility through their financial support.

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2.0 SCOPE OF PROJECT When this project was initiated it was intended to be a regional geological and geophysical evaluation of the southeastern Peruvian Sub-Andean Basins focusing on the identification of new play types. It was hoped not to be a rework of previous Ucayali/Ene Basin studies of which there have been a number of excellent ones. The focus was to examine the Basin in slightly a different manner than others had before in the past. The manner in which to do this was though the interpretation of a seamless digital seismic and well data set, with each being tied to one another combined with an analysis of the exploratory drilling history in the Basin since 1990. Supplementing the work done by the PARSEP Group were two additional studies: 1. Geochemical: by Hans Von Der Dick, ChemTerra International Ltd. 2. Tectonic: by Tony Tankard, Tankard Enterprises Although both of these studies were originally initiated for the Marañon Basin study (PARSEP, 2002), they were sufficiently regional in nature to have application for this evaluation of the Ucayali Basin. One of the more time consuming aspects of this evaluation was the standardization and quality control of the data. Digital curve data was compiled and corrected for each of the New Field Wildcats in the Basin (Figure 2). A composite log for each well was constructed, which if available included a Caliper, SP, Gamma Ray, Deep and Shallow Resistivity, Density, Neutron and Sonic curve. These composite logs are available as an LAS file as part of this report. A series of 9 cross-sections were strung across the Basin to standardize the stratigraphy that was to be utilized in the geological mapping module of this project. Where possible, a synthetic for each of the wells was made and tied to seismic. A standardized well database in Access was developed in which is included every new field wildcat well in the Basin with standardized well tops, and other information when available was input. The principal seismic data set utilized and interpreted in the project consisted of over 14,000 kilometers of 2D SEGY data, which represents coverage throughout most of the Basin (Figure 2). Perhaps one of the more notable accomplishments of this study was in the assemblage of this data set. Seismic data acquisition on this project began in November 2001 and has continued on through to the time of this writing. Clearly the lack of readily accessible data in the earlier stages of this project was a major roadblock for the group with respect to the completion of this study. A further complication was the realization that after 50% of the data had been loaded and partially interpreted on the workstation, was that the navigational data supplied to the group was incorrect. To correct this Perupetro brought in a contractor to correct the errors by going back to the original field records and maps. All data was then standardized to a UTM WGS-84 grid, and reloaded. Despite all these quality control steps, the data set although much better than what was previously available, is far from being perfect. One of the current discrepancies is between wells and seismic locations as there is not an exact 1 to 1

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SantaSanta ClaraClara 1A 1X Rayo 1X

Huaya 4X Huaya 3X

Insaya 1X

Maquia 1X Cachiyacu 1X

Amaquiria 1X Pacaya 1X Inuya 1X Cashiboya 1A

Cashiboya Sur 1X

Pisqui 1X Coninca 1X Coninca 2X Tiruntan 1X

Tahuaya 1X Rashaya Sur 1X

Aguaytia 1X Zorrillo 1X

Aguaytia Sur 4XD Neshuya 1X

San Alejandro 1X Chio 1X

Tamaya 1X Agua Caliente Caliente 1A 1X Agua Chonta 1X

Huallaga Northern Ucayali Fold and Thrust Belt

Platanal 1X

Sanuya 1X Shahuinto 1X

Rio Caco 1X La Colpa 1X

Runuya 1X

Shira Mountains Oxapampa 17C 1

Oxapampa 19 1 Oxapampa 19 2

Oxapampa 07 2 Oxapampa 07 1

Oxapampa/ Ene Fold and Thrust Belt

Mashansha 1X

Sepa 1X

Ene ‘Basin’

Panguana 1X

Camisea Fold and Thrust

Mipaya 1X

Pagoreni 1X San Martin 1X

Armihuari 4X Cashiriari 3X

0 km 0 Miles

50 km 30 Miles

Figure 2: Location of the Seismic and Wells utilized in the study of the Ucayali Basin

13

correlation. Well coordinates were obtained from a multitude of sources utilizing different grid systems. After converting the locations to a UTM WGS-84 grid, a bestfit approach was taken utilizing various data sets as certain groups of wells from one data set fell nicely on seismic line intersections in one part of the Basin and not in another. Clearly this is an issue that needs to be addressed in future studies. As mentioned previously, the study as it was originally proposed was to include separate reports on the Ene and Madre de Dios Basins. Within the Ene Basin there are only six seismic lines available all showing considerable structuration as a result of intense imbricate faulting and consequently there was little in which to support a separate report. In the context of this study, the Ene Basin is considered to be simply a continuation of the thin-skinned deformation front which extends south from the Huallaga Basin and through the Oxapampa wells located directly north of the Ene Basin as it is currently defined. This thrust front in part overrides the Shira Mountains, an older positive feature, which ultimately dissects the front, separating the Oxapampa-Ene segment from the Camisea segment. As such, the Ene Basin and Ucayali Basin analysis has been incorporated into one single report.

Sepa 1X

Panguana 1X

Mipaya 1X

Pagoreni 1X San Martin 1X

Armihuari 4X Cashiriari 3X

Cariyacu 1X

Los Amigos 1X

Puerto Primo 1 Pariamanu 1X

Karene 1X

Candamo 1X

Candamo 1X Well

Figure 3: Location of Madre de Dios Basin area and the available seismic data (in red)

The Madre de Dios Basin (Figure 3) however is somewhat more isolated from the Ucayali than is the Ene Basin as well as being seismically disconnected (no real contiguous data sets) from it as well. As a result this Basin will be covered within its own separate report. The well data sets (Las and Access) of the Madre de Dios Basin, however is included within the Ucayali data set on CD in the Appendices of this report.

14

3.0 PREVIOUS WORK IN THE STUDY AREA Drilling activity in the sub-Andean Basins of Peru began in 1937 with the drilling of Ganso Azul #1 to test the Agua Caliente surface structure located in the Ucayali Basin. This well discovered oil pay in the Cretaceous Cushabatay Formation at 311 meters. The well was twinned and flowed 2000 BOPD of 43o API oil with an open choke. Five more wells were drilled on the structure eventually proving up 14.7 MMBO. Subsequent to the development of the Agua Caliente Field, during the 40’s and 50’s, numerous companies were doing fieldwork in the sub-Andean Basins of Peru and as a result several more wells were drilled. The next discovery, however, was not until 1957 with the discovery of the Maquia Field. This was made by the El Oriente Oil Company just west of the Contaya Arch in the northern Ucayali Basin. This small field (20 MMBO) was put on stream with the 37o API oil being barged to refineries in Iquitos and Pucallpa. Contemporaneously with this discovery, the Cerro De Pasco Petroleum Corp. drilled five dry holes with gas shows near Oxapampa within the Ucayali fold and thrust belt to the west of the Shira Mountains. During this time in 1962, Mobil made a gas condensate discovery with Cretaceous reservoirs at Aguaytia in the central Ucayali Basin. This field did not live up to its initial promise and plans for a gas pipeline to Lima were cancelled. Through most of the remainder of the 60’s and into the early 70’s, exploration was virtually none existent as the petroleum concession system had been annulled by decree. By the beginning of the 1970’s the Peruvian Sub-Andean production from Maquia and Agua Caliente, at 2,500 BOPD, comprised less than five percent of the country’s output. The Sub-Andean Basins of Peru in 70’s saw a renewed interest in exploration with significant discoveries being made in the Marañon Basin of northeastern Peru and the Oriente Basin of Ecuador. During this time, six exploratory wells were drilled in the Ucayali Basin, one each by El Oriente and Hispanoil and four by Burmah Oil. All were D&A. To the south of the Ucayali Basin in the Madre de Dios Basin, in the mid-70’s, Cities Service and Andes Petroleum shot seismic and between them drilled five dry holes. In the southern Ucayali Basin, Shell Oil in 1978/80 after extensive field geological studies, signed blocks 38 and 42. Their first well within the foreland area of Basin, Sepa 1X recovered a small amount of oil from the Carboniferous before it was ultimately abandoned. This was followed up with the San Martin 1X well within the fold and thrust belt of the Ucayali in 1983 which flowed 41 MMCFGPD Gas and 1,626 BCPD from a Cretaceous/Permian section. The next wildcat by Shell, Cashiriari 1X was drilled in 1986 and flowed 56.7 MMCFGPD and 1,553 BCPD from a section similar to that tested by the San Martin 1X well. One appraisal each of these two fields was drilled indication reserves over 8 TCF gas and 300 MMB condensate, with considerable upside. Shell also made several other gas discoveries afterwards but nothing replicating the success of the San Martin and Cashiriari discoveries. By 1988, however, Shell had been unable to reach an agreement with respect to developing these discoveries and ceased all exploration activities. At this time, Shell 15

also relinquished the Madre de Dios Basin foothills acreage where they have recorded 500 km of seismic. Other activity in the Basin during the 80’s included 4 wells by Petroperu and 2 by Occidental Petroleum. Despite the occurrence of significant oil shows in several of these wells, all were plugged and abandoned. The 90’s saw Petroperu drill their last well in the Basin, the Cachiyacu 1X well in the northern Ucayali Basin in 1992. Shortly there afterwards, the legal framework, which currently governs the exploration and exploitation of hydrocarbons, was passed in August 1993 allowing companies to operate under either a Service or License contract. In November 1993, the Peruvian government set up a new state agency, Perupetro, to deal with contract negotiations, on the governments behalf, talking over Pertroperu’s former role. As a result, industry’s interest in Peru was heightened and several new blocks were signed. Activity further increased in 1996, which also saw the initialization of the privatization process of Petroperu. Although never completed, Petroperu sold all their producing properties and left the upstream sector. Drilling and leasing remained active through the rest of 90’s. Six exploratory wells were drilled during this time with no success. During this time Shell returned to once more make an attempt of making the Camisea project a reality, which included the drilling of the Pagoreni 1X gas/condensate discovery well in the area, but negotiations broke down with the government, and Shell abandoned the project. The concession containing the giant Camisea gas project was won by Pluspetrol in the year 2000. They have worked since then on bringing the project closer to production. The only exploratory well drilled in the Basin was done so by Repsol in the central portion of the Basin in 2002. It was plugged as a dry hole with oil shows in the Paleozoic section. A chronological listing of new field wildcats drilled in the Ucayali Basin is presented in Appendix 1.

16

4.0 GEOLOGY OF THE UCAYALI/ENE AREA 4.1 GENERAL BASIN DESRIPTION The Ucayali Basin is one of the sub-Andean Basins of Peru (Figure 1) with a prospective area of 105,000 km2 and some 5,000m of sedimentary infill. The Basin borders on the Brazilian Shield to the east and extends 650 km in length south from the Marañon Basin to the Madre de Dios Basin and 250 km in width east from the Fold Thrust Belt to beyond the Brazilian border. It has been discontinuously explored since 1939 with much of the basin still remaining under-explored. Seismic and well data indicates that an almost complete composite sedimentary section of Paleozoic, Mesozoic and Cenozoic ages was deposited in the Basin. However, the Basin’s present configuration shows a discontinuous preservation of the pre-Cretaceous sedimentary succession overlying the crystalline Basement revealing a complex tectonic evolution that involved most phases of the Caledonian and Hercynian pre-Andean and Andean aged tectonic events. The sedimentary fill of the Ucayali Basin is fairly similar to the southeast Marañon Basin, comprising up to 3000m of Tertiary continental molasses clastics overlying westerly thickening wedges of mainly marine Cretaceous Jurassic and Triassic, and an extremely variable section of Paleozoic. The principal difference between the two basins are; a) the thinning of the Cretaceous section from north to south as it onlaps a progressively elevated Paleozoic section (Figure 19), and b) a dramatic thickening of the Paleozoic section through a southerly thickening of Devonian and a Carboniferous Ambo section, and increased erosional preservation of Permian sediments beneath the Cretaceous unconformity. The dominant structural form of the Basin is major basement-involved thrusting which in many cases is the result of reactivated Paleozoic normal faults, and along its western margin, it is one of detached thrusts along almost its entirety. The western thrust front is interrupted north of the Oxapampa area by an inferred lateral ramp with the northern section being offset to the west, and south of the Ene ‘Basin’ by the Shira uplift, which separates it from the Camisea Fold and Thrust Belt (FTB). This later segment contains the giant Cashiriari and San Martin Gas Fields. For clarification purposes, this study considers the Ene Basin to be just a continuation of the Oxapampa fold belt west of and abutting against the Shira Mountains to its east. At present, three oilfields (Agua Caliente, Maquia and Pacaya) and five gascondensate fields (Aguaytia, San Martin, Cashiriari, Pagoreni and Mipaya) have been discovered in the Ucayali Basin. Maquia and Agua Caliente fields are currently the only producing oil fields, with the Pacaya Field being shut-in. Of the five gas condensate fields only Aguaytia is on production although the Camisea fields are under development and expected to be on production in the near future. The main reservoirs in the Basin are Cretaceous continental and marine sandstones with subordinate Upper Permian lacustrine, eolian and restricted marine sandstones. Despite the insignificant current oil production (approx 600 bopd) from three small oil and gas fields, the presence of the giant Camisea Field (13 TCF of gas and over 500 17

MMBC) in the southernmost part of the Basin has offered sufficient encouragement to keep companies exploring for hydrocarbons in the Basin. Many large structures are still untested and the presence of light oil shows encountered in the majority of the wells mark this region as one of the more promising onshore areas in Peru. The available data appears to indicate that the lower Paleozoic section has fair reservoir potential and some possible oil source potential (Cabanillas) in parts of the Basin, which has not been adequately tested. The Upper Paleozoic section (Carboniferous and Permian) exhibit good source rock potential in the shales of the Ambo Group and Ene Formation, and fair to good reservoir quality potential in the sandstones of the Ambo and Tarma Groups (Green Sandstones) and Ene Formations. The Mesozoic section, although thinning from north to south, also has good quality reservoirs within the Oriente Group and Chonta and Vivian Formations. 4.2 REGIONAL GEOLOGY The Ucayali Basin includes thick sedimentary stratigraphic sequences that extend far beyond the present Ucayali Basin and merge with the greater Marañon and the Acre and Solimoes basins in Brazil and eventually pinch out onto the Brazilian and Guiana Shields. The geological evolution of the greater Ucayali Basin area is controlled by two regional tectonic systems recognized in the sub-Andean basins of Peru. The first, the pre-Andean System, encompasses three cycles of Ordovician, Devonian and Permo-Carboniferous ages overlying the Precambrian basement of the Guyana and Brazilian Shields. The second, the Andean System, was initiated with the beginning of subduction along the western margin of Peru. It encompasses several megastratigraphic sequences and numerous minor sedimentary cycles, ranging from Late Permian to the Present. The stratigraphic column that has been used by PARSEP in the Ucayali Basin is representative of all NE Peru and is presented in Figure 4. 4.2.1 Pre-Andean System The pre-Andean tectonic cycle includes Ordovician, Silurian, Devonian and the Permo-Carboniferous cycles all overlying crystalline/metamorphic Basement. This tectonic system preserved discontinuous successions of Ambo/Cabanillas/Contaya and a more continuous Tarma/Copacabana/ and Ene/Red Bed Groups which reveal complex tectonics that includes a possible pre-Cabanillas rifting and peneplanation and a late Permian uplift and erosional episode. Ordovician aged sediments initiate the pre-Andean cycle and are represented by the siliciclastic Contaya Formation. In NE Peru, as found within the Marañon Basin, the Contaya Formation has a thickness of up to 150m. A maximum thickness of 4500m, however, has been reported for the cycle in the Eastern Range of southern Peru. The Contaya Formation outcrops in the Contaya Mountains of the northern Ucayali Basin. Although not within the studied basins, next in the succession is the Silurian, which is represented by argillites, flysch and tillites, and can reach thicknesses up to 1000m in southern Peru (Laubacher, 1978). The Silurian cycle merges with that of the Devonian, which is comprised of sediments of the Cabanillas Group. Cabanillas aged sediments have been deposited in the Madre de Dios, Ucayali and Marañon Basins. 18

PARSEP

Parsep

NE Peru

Upper Puca Pozo Shale Pozo Sand

Pozo

Pozo Lower Puca

TERTIARY

Nieva

CRETACEOUS

Vivian

Vivian

M arañon Pebas Chambira Pozo Shale Pozo Sand

Yahuarango

Santiago SS

Cachiyacu

Chonta

Chonta

Upper Chonta Chonta Lmst

Evaporitic Unit

Condorsinga Aramachay Chambara

Sarayaquill

Red Beds

Pucará

Sarayaquillo

Pucará

JURAS TRIAS

Cushabatay

Ucayali

Ipururo Chambira Pozo Shale Pozo Sand

Ipururo Chambira Pozo Shale Pozo Sand

Yahuarango

Yahuarango

Yahuarango

Upper Vivian

Upper Vivian Cachiyacu

Vivian

Casa Blanca Huchpayacu Cachiyacu Vivian

Lower Vivian

Chonta

Chonta

Chonta

Agua Caliente

Agua Caliente

Agua Caliente

Petroperu Huallaga

PARSEP Ucayali South

Corrientes Upper Red Beds Pozo Shale Pozo Sand

Lower Red Beds

Upper Vivian Basal Tertiary Huchpayacu Cachiyacu Cachiyacu Lower Vivian Vivian

Chonta shale Chonta Lmst Chonta Sand

M arañon Pebas Chambira Pozo Shale Pozo Sand

Capas Rojas Superiores

Yahuarango

Capas Rojas Inferiores

Upper Vivian Huchpayacu Cachiyacu Lower Vivian Pona Lupuna Upper Cetico Caliza

Pozo

Cachiyacu

Cachiyacu

Lower Vivian

Chonta

Low ChontaSd

Lower Chonta Agua Caliente

ORD DEV CARB PERM

Oxy

Corrientes

BasalChontaSd

Lower Cetico

Agua Caliente

Agua Caliente

Raya

Raya

Raya

Raya

Raya

Raya

Cushabatay

Cushabatay

Cushabatay

Cushabatay

Cushabatay

Cushabatay

Sarayaquillo

Sarayaquillo

Sarayaquillo

Sarayaquillo

Red Beds Evaporitic Unit

Condorsinga Aramachay

Pucará

Pucará

Pucará

Pucará

Chambara

Sarayaquillo

Q

PARSEP Ucayali North and Ene

Marañon

Red Beds

Agua Caliente (1)

Absent

Evaporitic Unit

Condorsinga Aramachay

Pucará

AGE

Santiago

Chambara

Pucará (Pongo M ainique) Red Upper SS Fm

Mitu

M itu

Mitu

Mitu

M itu

M itu

M itu

Ene

Ene

Ene

Ene

Ene

Ene

Ene

Copacabana

Copacabana

Copacabana

Copacabana

Copacabana /Tarma

?

Tarma

Tarma

Tarma

Copacabana

Copacabana /Tarma

Bed M id Mudstone Fm Group Lower SS Fm (2) Shinai M ember Ene Noipatsite Mbr Ene SS M br Copacabana /Tarma

Green Sandstone

Green Sandstone

Ambo

Ambo

Ambo

Ambo

Ambo

Ambo

Ambo

Cabanillas

Cabanillas

Cabanillas

Cabanillas

Cabanillas

Cabanillas

Contaya

Contaya

Contaya

Contaya

Contaya

Contaya Basement

(1) Basal Chonta + Upper Nia Kaatsirinkari

(2) Low er Nia Kaatsirinkari

Figure 4: Stratigraphic Columns for the Sub-Andean Basins of Peru, highlighting the Ucayali Basin

In the south of Peru, Devonian sediments reach thicknesses of up to 2000m, while in northern Peru, the maximum thickness attained is 1000m. Unlike the Marañon Basin, rocks of Devonian age are quite extensive in the Ucayali Basin, particularly in its southern half and have been encountered in a number of wells, and thick sequences can be seismically identified in the South-Central Ucayali Basin. An example of such is shown in Figure 5 where up to 600 msec of Devonian sediments (and possibly older) can be mapped within a series of isolated half grabens.

19

Figure 5: Composite seismic line through the South-Central portion of the Ucayali Basin showing a) the magnitude of the Devonian-Ordovician (?) rift Basins, b) the onlap relationship of the Carboniferous Ambo onto the Eohercynian Unconformity, and c) the truncation of the Paleozoic sequences beneath the Nevadan Unconformity at the Base of Cretaceous

20

Figure 6: Seismic Line in the south central Ucayali Basin showing a significant amount of erosion on the pre Ambo sequences (Devonian) beneath the Eohercynian Unconformity (dk. blue reflector).

21

In Late Devonian, the large Arequipa granitic terrain docked into the western South American Continent. The Pisco Abancay deflection is more or less coincidental with the north boundary of this block and the southern boundary is in turn marked by the Africa deflection in northern Chile (Anadarko, 1999). The docking of this large terrain probably produced the Eo-Hercynean compression in the Late Devonian and resulted in a major unconformity underlying sediments of Carboniferous age (Figure 6). The Eo-Hercynean compressional event affected the Ucayali Basin directly as it produced a swarm of north–south oriented faults. Many of them are left lateral transpressive, and accommodated the Arequipa Massif as it docked into place. These north-south faults are very important as they established the structural grain of the weakness in the basement of the Ucayali Basin and have been reactivated in one fashion or another every time the area was subject to diastrophism. For instance the north-south grain has been affected by structural inversion through wrenching, caused by Andean compressive episodes in the Late Cretaceous and Tertiary. The Permo-Carboniferous is next in the succession and is found resting unconformably over the Devonian Cycle (Figure 6) and/or Ordovician sediments and Basement in the uplifted areas. Rocks of this age have a widespread distribution throughout the Andean Range, the subsurface of the Peruvian eastern basins, and in the Brazilian Acre and Solimoes Basins. In the Peruvian basins, the earliest Carboniferous sedimentation began with the Ambo Group, which was deposited as continental to shallow marine, fine-grained sandstones, with interbedded siltstones, gray shales, and occasional thin coal beds. These sediments are followed vertically by the thin transgressive, clastic-rich Tarma Formation, which is overlain, usually conformably, by the normally thick, massive shelf carbonates of the Copacabana Formation. The Tarma-Copacabana Group is widely distributed in most of the Andean basins. It is predominantly a marine carbonate sequence although the cycle begins with a basal fine- to coarse-grained sandstone, the Green Sandstone Unit. This is overlain by a thick sequence of dark gray, fossiliferous limestones (wackestones, packstones and grainstones), and thin interbeds of dark gray shales and anhydrites. The unit contains several intervals with characteristic fusulinid forams of Permian age. The Copacabana limestones covered most of Sub-Andean Peru with the exception of the Contaya Arch and several other structural highs, where the Cretaceous overlies rocks of lower Paleozoic age. The Copacabana Formation in turn, was conformably overlain by the Ene Formation, a sequence containing black organic rich shales, dolomites and minor sandstones. 4.2.2 Andean System The Andean System was initiated simultaneously with the beginning of subduction along the Pacific margin. A major change in the tectonic regime along the northwestern border of the South-American plate promoted isostatic rearrangements. In a global scale, the initial phase of the Andean System developed during the Pangaea break up (M. Barros & E. Carneiro, 1991). The development of the Andean subduction zone during late Permian to early Triassic times is supported by geological information gathered by Audebaud, et. al. (1976) along the Peruvian Eastern Range, where they recognized a Permo-Triassic continental volcanic arc. The volcanic Lavasen Formation, which is seen in outcrops unconformably underlying the Mitu

22

Group to the west of the Huallaga Basin (Serie A: Carta Geologica Nacional, INGEMMET Bulletin No. 56, 1995) could be a remnant of this arc. The Lavasen Formation is also found intruding older rocks such as the Ambo Formation. Its lower member is a volcanic-sedimentary sequence with interbedded red clastics. The upper member is comprised of thick lava flows and breccias. In a study done for PARSEP on the “Tectonic Framework of Basin Evolution in Peru” (A. Tankard, 2001), Tankard correlates the Juruá Orogeny with the onset of our above-defined ‘Andean System’. Towards the end of the Permian, relaxation of the earlier extensional basin forming stresses that culminated in the deposition of the late Permian aged Formations were interrupted by a regional uplift and a pronounced unconformity that marks a first order sequence boundary after Ene-Red Bed Group accumulation. This event is believed by Tankard (2001) to correspond to the Juruá event identified in the Acre and Solimoes Basins of the Brazilian upper Amazon. Tankard (2001) describes a three-part cycle of basin formation and sedimentation that is repeated throughout the Phanerozoic of South America. Typically each cycle consists of (1) an early phase of rift-controlled subsidence and deposition of relatively coarser-grained clastics, (2) abandonment of individual fault controlled subsidence and yoking together of the various depocenters into a shallow epeiric basin, and deposition of a widespread cover of finer clastics and potential petroleum source rocks, and (3) a marked change in the stress fields resulting in structural inversion, uplift and Orogeny. The Late Permian – Middle Jurassic tectono-stratigraphic cover accumulated in a compartmentalized basin complex. This is demonstrated seismically in Figure 7 and in map form, in Figure 8 (Late Triassic – Middle Jurassic). The cover succession consists of Mitu red beds in isolated rift segments, accumulation of finer-grained Pucará clastics, limestones and evaporites, and termination in the widespread Sarayaquillo blanket. Initiation of subsidence and deposition of the Mitu Formation is attributed to a process of orogenic collapse following the late Hercynican Juruá Orogeny. A regional supratidal sabkha environment developed at the transition between the Pucará and Sarayaquillo Formations, which marks the beginning of the continental and shallow marine deposition. Of stratigraphic significance to the western Ucayali/Ene Basin area is the evaporitic unit associated with the sabkha deposition. This unit has been tentatively named the Callanayacu Formation by Advantage who completed extensive fieldwork in the fold and thrust belt between the Huallaga and southern Marañon Basins (Advantage 2001). In the Peruvian Fold and Thrust Belt this evaporitic unit can be traced over a distance of at least 700 km. These deposits were intersected in subsurface by the Oxapampa 7-1 and Chio 1X wells in the central part of the Ucayali Basin (Appendix 2e to 2h), and by the Putuime 1X well of the Santiago Basin in its north. In between, extensive deposits of evaporites have been identified in outcrop in the Huallaga Basin, and in the Fold Thrust Belt of the westernmost Ucayali Basin. With further regression of the Jurassic sea the Pucará and Callanayacu Formations were overlain by Middle to Late Jurassic continental red beds of the Sarayaquillo Formation.

23

Cretaceous

Sarayaquillo Pucará Copacabana

Ene

Mitu

Unflattened section Cretaceous Sarayaquillo Pucará

Ene Mitu

Copacabana

Flattened on Base Cretaceous Unconformity Cretaceous

Sarayaquillo Pucará

Mitu

Ene

Copacabana

Flattened on Pucará Formation Figure 7: Seismic line OR-95-08 in the northern Contaya Arch area showing the evolution of a Late Permian to early Mesozoic extensional basin through the use of different datums (flattenings) (after PARSEP, 2002)

24

Figure 8: (After Tankard, 2001) Late Triassic – Middle Jurassic paleogeography. The locus of sedimentation was the extensional tract between the Contaya (csz) and Shionayacu (ssz) shear zones. Isopachs show that the stratigraphy terminated abruptly against NE-striking faults, and for this reason they are described as basin sidewall faults. psz, Pucalpa shear zone; sol, Solimoes Basin.

25

Termination of the Sarayaquillo deposition coincides with the later part of the Jurassic, which is represented by the regional Nevadan unconformity over which lies sediments of Cretaceous age. This is a boundary generally well recognized on seismic, below which the Jurassic is seen to thicken westward and locally subcrop with considerable angularity. Cretaceous deposition was initiated in the greater Marañon/Ucayali Basin during Neocomian-Aptian times and was characterized by a westerly thickening wedge of fluvial to marginal clastics occasionally punctuated by carbonate sedimentation. The Cretaceous epeiric sea deposition terminated during the Late Cretaceous with the arrival of the first pulses of the Andean Orogeny (Peruvian and Incaic Phases) at which time through to Middle Eocene time, molasse-styled deposition dominated the Basin. This was punctuated during the Late Eocene to Early Oligocene by a marine transgression that resulted in the deposition of the Pozo Formation, which is restricted to the northern basins and to the north Ucayali. Molasse deposition resumed in the Late Oligocene, which culminated during the Miocene Quechua deformation and has continued through to the present. 4.3 GEOLOGY OF THE UCAYALI/ENE PROJECT AREA 4.3.1 Project Overview PARSEP constructed a digital database from geological/geophysical data gathered from an extensive set of old and recent exploration activities that were made available to the group through the Perupetro technical archives. It was this database that was updated and subsequently used as the basis for the geological interpretation of the Ucayali/Ene Basin. The main database consists of wire-line logs and data from 40 new field wildcats and over 15,000 km of 2D seismic data. The seismic data set provided for the Ene Basin was of an earlier processed version than the one used by Elf in their evaluation of the Block 66 and was of considerably less quality. As a result, the Elf interpretation was utilized for the evaluation of the Ene Basin area. The Ucayali project is largely comprised of five subprojects: a) Collection and standardization of geological information; b) The stratigraphic cross-section grid project utilizing the data from (a); c) Collection of SEGY seismic data, navigational data corrections and tying the various data sets; d) Geophysical interpretation; and e) Structural profiles. a) Collection and standardization of geological information – Geological well data and tops were collected and put into an ACCESS data base that was used as the preliminary data set for interpretation. This information was gathered from literature and PARSEP correlated well logs. The database was continually updated reflecting changes and additions as the interpretation progressed. The final ACCESS database is included as Appendix 5 in this report and LAS files of the composite wells logs used for the interpretation as Appendix 6. In the Marañon Basin study done by PARSEP (2002), numerous geological maps were created from a similar type database and presented as enclosures in the report. The tectonic style, significant pre-Cretaceous uplifts and erosion, lack of significant well control and the biased sampling of what

26

was tested by those few wells, were not conducive to the creation of meaningful geological maps from well data. As a result, only seismic was utilized for generation of the maps in this project. The one exception was an isopach of the Cretaceous, which was created simply to show the regional thinning of the mapped interval from north to south in the Ucayali Basin. This map is presented in Figure 19 within section 4.3.2.8 b) The stratigraphic cross-section grid project - The cross-section grid consists of ten regional stratigraphic sections (Enclosure 1b), which was designed to include almost all the wells in the Basin. The sections were created to construct the regional stratigraphic framework of the Basin, particularly within the pre-Cretaceous section and are referred to extensively in the stratigraphy section 4.3.2, and presented as Appendices 2a to 2j in this report. c) Collection of SEGY seismic data, navigational data corrections and tying the various data sets – This section is discussed in detail in the Geophysics Section 5.0 of this report. d) Geophysical interpretation – The geophysical interpretation was done in two parts, the northern Ucayali which extends from the southern Marañon Basin to just north of the Oxapampa wells in the western part of the Basin and north of the La Colpa well in the eastern part of the Basin. The division represents a discontinuity in two largely continuous data sets of almost equal size. Additionally, changes in geology between the northern and southern Basins resulted in different reflectors and intervals in both areas to be mapped. In the northern Basin, TWT maps were made on, Pozo, Base Cretaceous, Copacabana, and Contaya and isochrons of the Pozo to Base Cretaceous, Base Cretaceous and Top to Base of the Jurassic salt intervals, while in the south, TWT maps were made on the Upper Cretaceous (near Chonta), Base Cretaceous, Tarma, Devonian and Basement and isochrons – Cretaceous, Upper Cretaceous to Tarma and Top Devonian to Basement. These maps are all discussed in detail with the Geophysical Section 5.0 of this report. Three other geophysical maps are included in this report that were done independently of the regional geophysical mapping project. They were a TWT map on the top of the Ene (Figure 12) created largely to show the distribution of the Formation throughout the Basin, an isochron of the Ambo section in the southern Ucayali (Figure 9) to emphasis the probable Ambo source kitchen area for the Camisea area and a lower Cretaceous channel map (Figure 45) in the area of the Mashansha well in the southern Ucayali Basin e) Structural profile project – The structural profile study for the Ucayali/Ene Area was completed through the compilation of the available seismic data, exploratory wells, geological field data and maps, and the PARSEP seismic mapping. Generally speaking, the six dip sections through the Basin were constructed by tying the geological field data from the Ingemmet quadrangle maps in the Andean fold and thrust belt to the west, with the seismic and well data in the sub-surface of the Ucayali Basin to the East. Additionally, both geological and geophysical interpretations available through various reports within the Perupetro archives were also utilized in areas of minimal PARSEP data coverage. The geological profiles are presented in Enclosures 3a to 3f

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and discussed in detail in section 4.3.3 . One additional section, (Figure 22) is also presented in this report as a representative structure profile through the Ene Basin, 1f, that has been taken from Elf’s Final report on Block 66 (Elf, 1996). 4.3.2 Stratigraphy of the Ucayali/Ene Area One of the intentions of this study was to standardize the stratigraphy of the Ucayali Basin as presented in Figure 4. The most critical and difficult aspect of this exercise was the tying of correlations between the northern Ucayali Basin and the Mainique Gorge/Camisea area of the southern Ucayali Basin. In the later, important modifications were introduced by Shell (1997) within the Permian and Cretaceous stratigraphic sections after the Camisea gas discoveries. The modifications made by PARSEP are in line with our intent to present a consistent digital database to facilitate mapping and interpretation. Discussions are presented where previous assumptions and conclusions were found to be contradictory (or in question) through our evaluation of the data. The intention is to keep the stratigraphy as simple as possible without introducing unknown or contradictory names. Unfortunately, at the termination of this project there are still a number of unanswered questions relevant to stratigraphy that may form the basis for future studies. The composite stratigraphic column present in the Ucayali Basin includes a thick sedimentary succession of early and late Paleozoic, Mesozoic and Cenozoic age (Figure 4) and the stratigraphic cross-sections presented in the report show the widespread distribution of all these units throughout most of the Basin. It is interesting to note, however, that the sections show no single area drilled to date, with a complete stratigraphic section preserved. Where this may be found is in the foredeep area just east of the Fold Thrust Belt west of the Pisqui - Rashaya Sur – Aguaytia structural trend, and in the deep basinal area of the northern Ucayali Basin south and west respectively of the Cushabatay and Contaya highs. The Camisea discoveries of the southern Ucayali Basin in the 80’s, allowed for detailed stratigraphic studies to be completed that defined the extension and termination of the early Cretaceous units and the stratigraphy in the Cretaceous/preCretaceous section overlying the Copacabana Group. These discoveries introduced a controversy that we do not intend to solve with the present means allocated to the project. In this report, PARSEP uses Shell (1997) Cretaceous age units with name modifications below the Vivian and its late Permian age units and names overlying the Copacabana Group. The major characteristics of these stratigraphic intervals that are presented in this report for investigators not familiar with the data, are from the knowledge gained after the Camisea discoveries and updated through the additional work done by Shell in the late 90`s. Additionally, the lesser-known deeper Paleozoic stratigraphy is reviewed and condensed, since it also constitutes a potential play type throughout much of the Basin. The following section discusses the Ucayali Basin mega-sequences Paleozoic, Late Permian to Jurassic (Rift/Sag Phase), Cretaceous and Tertiary beginning first with a brief section on Basement.

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4.3.2.1 Basement Few descriptions on Basement rocks have been presented in the greater Ucayali Basin area. One reference, however describes the Basement east of the Contaya Arch across the border in Brazil (Ingemmet 1997, Bull 101,) at Xingu Complex which is composed of granitic and dioritic gneisses and metamorphics with a K/Ar age of 911 ± 13 and 877 ±42 my. Several wells in the Basin penetrated Basement such as in the Agua Caliente 1X well north of the Shira Mountains and the Platanal 1X, La Colpa 1X, Shahuinto 1X, Runuya 1X, Sepa 1X and Mashansha 1X wells east of the Shira Mountains in the south Ucayali (stratigraphic cross-sections 2, 4, 7, 8 and 10). In the Ene Basin area, Basement has been described from outcrops to its west as being Precambrian crystalline and possible sedimentary to metasedimentary rocks. 4.3.2.2 Ordovician The pre-Andean System begins with the Ordovician cycle and is represented by the Contaya Formation, a unit of gray and black laminated hard slates, which overlies Basement. A maximum thickness of 4500m has been reported for the cycle in the Eastern Range of southern Peru. The Contaya Formation outcrops in the Contaya Arch (150m thick) and 35km south of the Oxapampa wells in the northern and southern Ucayali Basin, respectively. It has been drilled in the Agua Caliente 1X well and possibly in the Cashiboya South well (stratigraphic cross-sections 2, 3, and 4) and its presence is interpreted by seismic across the northern Ucayali Basin. Other than the occurrence south of the Oxapampa wells referred to above, no Contaya aged rocks have been recognized in the Ene Basin area. 4.3.2.3 Silurian Next in the succession is the Silurian cycle which is represented by argillites, flysch and tillites, and can reach thicknesses up to 1000m in southern Peru (Laubacher, 1978). A portion of the monotonous clastic sequences drilled by Panguana 1X and Sepa 1X wells in the southern Ucayali may represent this cycle (stratigraphic crosssections 2 and 4) although the actual date of these sediments is unknown. The Silurian depositional cycle ends with an erosional episode that is the result of tectonic movement during the Caledonian/Taconian Orogeny in the Peruvian Oriente. The Silurian cycle merges with that of the Devonian Cabanillas Group that has been deposited in the Madre de Dios, Ucayali and Marañon Basins. 4.3.2.4 Devonian - Cabanillas Group Sediments of Devonian age have a widespread distribution reaching a thickness of up to 2000m in the south of Peru, while in northern Peru the maximum thickness seen is 1000m. Rocks of the Cabanillas Group of Devonian age constitute a well defined unit in the study area, and are found in outcrops in the Mainique Gorge and in the Sepa 1X and Panguana 1X wells in the south, and the Rashaya Sur 1X and Cashiboya 1A wells in the north (stratigraphic cross-sections 2, 4, 9 and 10). The presence of this unit is interpreted by seismic throughout much of the subsurface in both the southern and

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northern Ucayali Basin. The presence of Cabanillas aged rocks in the Ene Basin area is likely although this has never been conclusively confirmed (Elf, 1996). The Cabanillas Group is comprised of dark gray mudstones, shales, siltstones and sandstones. The mudstones are dark gray, micaceous, and iron-rich, weathering to red with a sulfurous stain. Generally, the unit is considered to have been deposited in moderately deep water as turbidite and hemi-pelagic deposits, which change upwards into sediments representative of shallow water deposition. In outcrops to the west of the Camisea fields, the upper section is represented by coarsening upward sequences recording episodes of progradation from shelf to deltaic sedimentation and eventually into sediments representative of a shallow basin environment. Each period of progradation ends in a flooding event that deposits a potentially organic-rich source rock facies that characterizes the Cabanillas sediments. The Cabanillas is absent in the northern Shira Mountains-Agua Caliente and to the east of this area in the Platanal-Shahuinto-Mashansha area (stratigraphic cross-sections 7, 8 and 10). 4.3.2.5 Early Carboniferous - Ambo Group

Possible Ambo Basin Hingeline

Figure 9: Isochron map of the Ambo Group in the southern Ucayali Basin

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In the Peruvian basins, the earliest Carboniferous sedimentation began with the Ambo Group. The Ambo Group is well known in the southern portion of the Basin where it is generally found overlying the Devonian Cabanillas Group and/or Basement. A gross thickness of 813m in the south diminishes to less than 300m in the La Colpa well area (stratigraphic cross-sections 7, 9 and 10). Its distribution in the northern portion of the Basin is not well known. From the seismic mapping completed by PARSEP, the Ambo Group is seen to thicken dramatically from north to south in the southern Ucayali Basin (Figure 9) with the Ambo sediments onlapping the underlying unconformity surface on Devonian and/or older horizons. In the area of the Mashansha well and to its north, the Ambo is very thin and in some areas, completely absent where basement paleo-highs exist. Moving from this area to south in the Camisea area, the Ambo section thickens dramatically to where over 600msec of Ambo section can be mapped overlying the Devonian. It is currently interpreted that the Camisea fold and thrust belt may be controlled by a major hingeline that was active during Ambo deposition as the Ambo section is seen to increase dramatically in thickness in close proximity to the termination of the Camisea fold and thrust belt. Additionally, it is believed that in the area of thick Ambo deposition, the Ambo was also one of the principal detachment surfaces for the decollement structures in the Camisea area. The Ambo consists predominantly of coarse and fine-grained terrigeneous sandstones with interbedded siltstones, gray shales, and with coal or organic rich interbeds deposited as continental to shallow marine and fluvial deposits. The coal and organic rich beds represent the initial transgression of the early Carboniferous Ambo Group. The unit includes a tidal/estuarine inter-deltaic lower section, a deltaic middle section and an inter-deltaic upper section. The middle deltaic portion has commonly TOC’s of 1.0 and locally over 8.0, and 18.0 wt% mainly humid organic matter with potential gas and oil generation capabilities. The Ambo Group is identified as the main source rock of the Camisea gas/condensate fields. These sediments are overlain by the thin transgressive, clastic-rich Tarma Formation (with its widely distributed basal Green Sandstone unit). The Ambo identified in the Ene Basin corresponds to a shallow siliciclastic platform from upper offshore facies to dominant delta front deposits (Elf, 1996). In its more distal facies, the Ambo consists of amalgamated storm beds that contain greenish sands containing coaly debris. 4.3.2.6 Late Carboniferous to Early Permian - Tarma/Copacabana Group The Tarma/Copacabana Group is by far the most widely distributed pre-Cretaceous unit in the sub-Andean basins, including the Ucayali and Ene Basins. Generally it is difficult to place an exact upper contact for the Tarma Group and the two units together are consequently often referred to together, as the Tarma/Copacabana Group. A separation of the Tarma and Copacabana groups can be established locally where the Tarma Group includes more clastic interbeds as in the Mainique Gorge area of the southern Ucayali Basin. The lower unit of the Tarma Group is a clastic unit that includes green sandstones, red siltstones, silty mudstones and anhydrite beds reaching 80 m. in thickness. The basal clastic unit of this interval is called the Green Sandstone member, which typically has good porosity and good reservoir potential. It is a green to brown, fine to very coarse cross-bedded, moderately sorted, glauconitic

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HUAYA 3X

HUAYA 3X 1600

2100

MITU?

THRUST FAULT I

1700

2200

ENE

1800

2300

COPACABANA

1900

2400

ANH

2000

2500

2100 2600

2200

THRUST FAULT I Figure 10: An example of a 50 to 60 meter anhydrite unit within the upper Copacabana section that has been repeated by a thrust fault. The log on the right is the hanging wall section and the one on the right, the footwall section. Note: The repeated section has been removed in the Huaya 3X well in the stratigraphic stratigraphic cross-sections 1 and 2. 2700

Chonta Base Cretaceous/Copacabana Tarma Ambo Devonian

Basement

Figure 11: West to East seismic line through the Panguana well showing a) how the Copacabana has been erosionally reduced beneath the Base Cretaceous unconformity and b) The anomalously thick section of pre-Ambo sediments intersected in the Panguana well. The Basement pick is very interpretive and base largely on the results of the Panguana 1X well.

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and chloritic sandstone. There is a sharp contact between the Green Sandstone and the underlying Ambo Group. The green colored clastics diminish upwards and the upper part of the Tarma Group comprises micritic wackestones and dark gray mudstones establishing a gradational contact with the overlying carbonates of the Copacabana Group. The carbonates become a sequence of thick units of dark gray micritic and sparite carbonates, white to light brown crystalline dolomites, cross-bedded oolites, wackestones and cherts with distinctive fusulinid rich horizons in the upper part (Mainique Gorge, Agua Caliente and San Alejandro 1X wells). The group also include some clean 1 to 3 meter-thick anhydrite beds, occasionally 5 m thick, as in the upper Tarma Group in La Colpa 1X well and in the bottom 2/3 in the San Martin 1X well. In the 1950-2050m interval of the Huaya 3X well a 50-60m thick anhydrite unit was intersected within the Copacabana section and is repeated between 2430-2500m by a thrust fault at 2200m (Figure 10). Thickness varies from 640 - 960m in the northern portion of the Ucayali Basin (see wells Huaya 3X, La Colpa 1X, Runuya 1X and Agua Caliente 1X in stratigraphic cross-sections 2 and 4) to 860 - 940m in outcrop in the Mainique Gorge and Atalaya areas (stratigraphic cross-section 9) and 990m in the Camisea San Martin 1X well (stratigraphic cross-sections 4 and 9), in the southern Ucayali Basin. Locally, the unit is partially reduced by erosion along the crests of Paleozoic aged structures such as in the Coninca 2X well were the Tarma/Copacabana has a thickness of 333m (stratigraphic cross-section 3) and in the Panguana 1X well where it has been reduced to 166m as demonstrated in stratigraphic cross-section 9 and seismically in Figure 10, or it has been completely stripped by erosion as in the Cashiboya area, (stratigraphic cross-section 1). In the area over the Contaya arch where there is no Copacabana, it is presently unknown whether the Contaya Arch was a positive feature during Copacabana deposition, (the result of an earlier tectonic uplift and the unit was not deposited as suggested by Mathalone (1994)) or whether it is simple a result of uplift and complete erosion as referred to in the examples above. If the latter is true, the Contaya Arch became a positive feature in Late Permian time. The Copacabana contains organic-rich dark gray to black mudstones deposited under flooding or anoxic conditions with source rock characteristics. Dolomitic wackestones interbedded with brown sandstones at various levels in the whole unit produce strong to faint oil smell in fresh broken surfaces. These intervals have TOC of 2.0 wt% and are mature for oil and gas generation in the Mainique Gorge, Shell (1997). Near the top, the carbonates are bioturbated and burrowed and are found underlying the basal Ene Formation mudstone, with no evidence of karsts or breccias. In the Huaya 3X well there is a common presence of dolomites observed near the anhydrite beds. These dolomites are brown gray and dark gray, locally vugular, micritic, oolitic and pelletoidal, which are remnants of the original limestones prior to dolomitization. The anhydrite/porous dolomite/organic rich carbonate association may constitute a potential petroleum system in this part of the Basin.

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Figure 12: Distribution of the Ene Formation as mapped seismically in the Ucayali Basin. The seismic line shown in Figure 14 is located on this map

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Figure 13: NW/SE stratigraphic cross-section flattened in the Upper Permian unconformity shows the late Permian post Tarma/Copacabana Group stratigraphy. Orellana 1X is in the SE Marañon Basin.

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4.3.2.7 Late Permian – Ene Red Bed Group The late Permian Ene Formation and the Red Bed Group conformable overly the Tarma/Copacabana Group and unconformably underlie the Cretaceous in the Camisea area, the area around the Tamaya well, and in a deep trough south of the Cushabatay Mountains and west of the Contaya Arch where seismic data reveal the presence of a thick Permian section of probable Ene age that extents into the areas drilled by the Orellana and Huaya wells. A map showing the seismically mapped distribution of Ene sediments is shown in Figure 12 and in its stratigraphic occurrence is shown in Figure 13. A seismic line through the northern Ene thick is shown in Figure 14. SW

NE

Pozo Chonta

Agua Caliente

Ene

Base Cretaceous Top Paleozoic

Copacabana Grn Sdst

Cabanillas

Contaya Basement

Figure 14: Seismic line CP739801 (located on Figure 12) through a thick preserved Permian section in the Northern Ucayali Basin. In an alternative interpretation, the Top Copacabana was picked at an alternative reflector, the pink mk below the Grn Sdst. If this surface were a significant unconformity, as it would appear from this seismic interpretation, this horizon would most likely represent the Devonian unconformity so readily visible in the southern Ucayali Basin, thereby supporting the interpretation presented above.

These units will be covered with more detail later in this report since their age, has been redefined after the Camisea gas/condensate discoveries in the late 80`s and updated in the late 90’s and it is not available in published literature. Previously much of this section was described as belonging to the Cretaceous Oriente Group.The extension of the late Permian age Formations to the west and SW of the Shira Mountains and adjacent and north of the Ene Basin is largely unknown and will require detailed field work. This is particularly true in the western Shira Mountains area where an abnormally thick Cretaceous Oriente Group (with individual Cushabatay, Raya and Agua Caliente Formations) and Chonta Formation are reportedly found, overlying the Copacabana Group (INGEMMET, 1997). The lower part of this section may have been a misinterpreted Permian section as originally was the case in the Camisea area.

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Figure 15: Stratigraphic cross-section flattened on Base Cretaceous shows detailed late Permian stratigraphy. Note excellent log correlation in Shinai, and two 10 m. thick anhydrite beds in the Middle Mudstone Formation and anhydrite beds in the Noi Sandstone Patsite Member.

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Ene Formation Presence of the Ene Formation is confirmed in outcrops in the eastern Shira Mountains from south of the Runuya 1X well down to the Mainique Gorge and in subsurface in the Camisea wells and in many wells in the eastern Ucayali Basin. Its presence is well known in the outcrops of the Ene Basin where is has been recognized as a potentially prolific source rock. Thickness of this formation varies substantially, being controlled by depth of erosion of the late Permian and Base Cretaceous unconformities. It is best preserved in the south Ucayali in the Sepa/Camisea/Mainique Gorge area where the unit is divided in three members (Shell, 1997), the Ene Sandstone, Noipatsite and Shinai Members with a thickness between 150 to 220 m, as shown in Figure 15 and stratigraphic crosssections 4, 9 and 10. The Ene Sandstone and Noipatsite Members are two 70-150 meter-thick sandstone bodies similar in rock character, and resting on a basal dark gray 6 meter-thick organic rich source rock mudstone with strong petroleum odor in fresh fractures. The mudstone overlies the Copacabana Group limestones with no signs of karstification or brecciation. This mudstone changes to black and dark gray siltstone in the area east of the north Shira Mountains and it disappears in the north Ucayali. West and to the NW of the Contaya Arch, a uniform 160-200m thick sandstone member possibly equivalent to Ene Sandstone/Noi Sandstone is preserved overlying the Copacabana Group in the Huaya 3X (identified by PARSEP based on lithostratigraphic regional correlation) and by Coastal in the SE Marañon Orellana 1X wells (stratigraphic crosssections 1 and 2 and Figure 13). The Ene sandstones in the Huaya 3X well are white, cream to light gray, very fine to medium-grained, sub-angular to rounded, with siliceous cement and non-calcareous. The Ene Formation (1690-1850m) overlies the Copacabana Group and it is capped by a conglomerate/sandstone unit (1620-1690m), which is overlain by a finer clastic red bed section (1620-1400m) tentatively assigned by PARSEP to the Mitu Group and Pucará, respectively. The conglomerate has clasts of granitic gneiss with quartz and feldspar phenocrysts and a medium to coarse quartz-feldspar and lithic fragments matrix. The Ene-Mitu-Pucará clastic sequence (1400-1850m), thus defined, was originally named Sarayaquillo Formation underlying the Cushabatay Formation and overlying the Copacabana Group in previous reports in the Huaya 3X. Additionally, PARSEP structural/stratigraphic interpretation in this well defines a repeated section of the Ene Formation and the upper limestones and anhydrites of the Copacabana Group as shown in Figure 10. In the Ene Basin, the Ene Formation consists of four units, a basal black shale overlain by a sandstone, then an upper black shale, overlaid by a dolomitic interval. As such it is more or less identical to the Ene identified in the southern Ucayali Basin (Camisea area). In the Ene Basin region the depositional setting for the Ene corresponds to a marginal marine (lagoonal) to coastal plain setting, with lagoonal black shales, fluvial to estuarine sandstones, and peritidal, possibly evaporitic dolomite.

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Shinai Member The Shinai Member is a 70-100 meter-thick organic-rich carbonate mudstone with algal laminates, oolites and wackstone carbonates preserved south of the Runuya 1X well (stratigraphic cross-section 4). Stable basin conditions allowed the unit to extend laterally with minor lithological changes, providing a distinctively characteristic horizon for log correlation in the Sepa/Camisea area (Figure 15). Red Bed Group/Mainique Biostratigraphic analyses in the Mainique Gorge/Camisea area reveal the presence of an uppermost sequence of late Permian age in the southern Ucayali Basin. This is the Red Bed Group, which is equivalent to the Mainique Group, and found overlying the Ene Formation (Shell, 1997). From bottom to top, this sequence is made up of the Lower Sandstone, the Middle Mudstone and the Upper Sandstone Units, as shown in the stratigraphic cross-sections 4, 9 and 10 and in Figure 15. This sequence was recognized in older literature as the Oriente Group, where each of the units represented the Cushabatay, Raya and Agua Caliente Formations, respectively. Its presence is restricted to the SW of the Runuya-Mashansha-Panguana structural trend. The unconformity at the base of Cretaceous has stripped off much of this section in the San Martin, Cashiriari and Pagoreni fields, leaving only the Lower Sandstone Formation or Lower Niakaatsirinkari Formation, in contact with the Agua Caliente Formation of Cretaceous age. Lower Sandstone – The Lower Sandstone Formation (Lower Niakaatsirinkari Formation) consists of massive arkosic to sub-arkosic, medium to coarse-grained arenites, with meter-scale cross-bedding suggesting an eolian origin although no frosted quartz grains were detected in outcrops. The dune complex is truncated from W to E (stratigraphic cross-sections 4 and 10) beneath the Cretaceous unconformity and based on paleo-current data, migrates westwards into a sabkha environment (Shell, 1998). The lower and upper contacts with the Shinai Member and with the Middle Mudstone Formation are sharp planar surfaces, as seen in outcrops and in wells Sepa 1X, Mipaya 1X, Pagoreni 1X and Armihuary 1X wells (stratigraphic cross-sections 4 and 10 and Figure 15). These wells have a maximum thickness of 90 to 130m, which contrast with the approximately 40m of the lowermost section preserved below the Cretaceous unconformity in the remaining wells in the San Martin and Cashiriari fields (Figure 15). Petrographic examination in selected intervals reveal its thinly laminated nature, and the alternation of well-sorted laminae with bimodally sorted laminae and the absence of detrital clays. This is also suggestive of an eolian origin. Middle Mudstone – The Middle Mudstone Formation is well developed in the Mainique Gorge and in the Mipaya 1X well, as shown in the stratigraphic crosssection 9 and Figure 15 where it is found to be 175 and 90m, respectively. The unit consists of a predominantly red mudstone, with a middle unit of red calcareous and dolomitic mudstones, thin micritic carbonates with rare anhydrite pseudomorphs in outcrops and with two very distinctive 10m thick massive anhydrite beds as seen in the Mipaya 1X well.

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Figure 16: Evolution of the post-Copacabana Permian and Cretaceous sequences in the Camisea area through flattenings in Noi, Shinai, Lower Nia, Mid Mudstone or Base-Cretaceous, Agua Caliente, Chonta and Vivian Formations

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Upper Sandstone – The Upper Sandstone Formation is only present in outcrops in the Mainique Gorge area, overlying in sharp planar contact the Middle Mudstone Formation, and underlying the Pucará Group (stratigraphic cross-section 9). It is a massive, medium to fine-grained unit with some coarse granular to pebbly layers and feldspathic sandstones moderately to well sorted. Trough and tabular cross-bedding up to several meters in thickness and petrographic examination suggests an eolian origin for several intervals. Permian/Cretaceous Basin Evolution – Camisea Area Figure 16 is a representation of the evolution of the late Permian and Cretaceous basin in the Camisea area through a series of flattening at various levels. Refer to Figure 15 for location of the Figure. The bottom section flattened on the Noipatsite Member, shows a thickening of this reservoir in the San Martin and Cashiriari fields. These units were not drilled in Pagoreni. The following section flattened on the Shinai Member, demonstrates the uniform nature of this unit, which makes it an excellent correlation surface in the area. In the following section a thin Lower Niakaatsirinkari or Lower Sandstone Formation is preserved below the Cretaceous, except in the Armihuary 1X and Pagoreni 1X wells to the NW, where quite a thick section remains. The flattening on the Base Cretaceous shows both the removal of most of the Middle Mudstone Formation and an important portion of the Lower Niakaatsirinkari Formation. The Agua Caliente flattening shows the sand-to-sand relationship with underlying Lower Sandstone Formation, which together form a single reservoir in Camisea. Generally there is a consistent thickness of Agua Caliente Formation throughout the area although there is some minor thinning seen over the Cashiriari field to the east. The final flattening, on the Chonta Formation, demonstrates the presence of an excellent regional seal for the Cretaceous and Permian reservoirs. A flattening on the Vivian (not shown) does not change appreciably from the one at Chonta time. In general, the Cretaceous and Permian formations have an excellent correlation over a distance in excess of 150km. 4.3.2.8 Triassic to Jurassic The early episodes of the Andean tectonic system are preserved in the western and NW extremes of the Ucayali Basin, where deep latest Permian/Jurassic basins were formed. These basins contain sequences of syn rift continentally derived sediments of the Mitu Group, overlain by a Triassic to Jurassic-aged marine to transitional unit dominated by carbonate deposition and evaporites, the Pucará Group. The Pucará is overlain by regressive continental redbeds of the Jurassic aged, Sarayaquillo Formation, which was deposited prior to the early Cretaceous regional episode of erosion and peneplanation, as shown in the stratigraphic cross-sections 1, 2, 5, 6, 7 and 8. The Permo/Jurassic mega-stratigraphic sequence is covered by a Cretaceous foreland and Tertiary foredeep sedimentary cover. Mitu The Mitu Formation is considered to be the syn-rift sequence associated with the initial opening of the combined proto-Marañon/Ucayali Basin. Within the Marañon Basin and surrounding areas it is deposited in a series of grabens (Figures 7) formed within a rifted Paleozoic section. From observations made during PARSEP

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sponsored field trips (PARSEP 2002), the contact between it and the overlying Pucará was observed to be conformable in several locations implying the two are part of the same mega-sequence. However, in most literature and published stratigraphic columns, the Mitu is often described as an unconformity bound unit and depositionally, separate from the Pucará Group. A thick Mitu Group was drilled by the Orellana 1X well in the SE Marañon Basin just to the north of the Ucayali Basin. In the northern Ucayali Basin itself a thin conglomerate with gneiss and granite pebbles, intersected by the Huaya 3X well is tentatively assigned to this group. With this exception, the Mitu Group has not been drilled in the Ucayali Basin and its occurrence is restricted to the Fold Thrust Belt where common outcrops are reported. The identification of the Mitu in the Ene Basin is considered ambiguous, as is the identification of most redbed sequences in this complex structural area. Typically the Mitu represents redbed deposition within a complex horst and graben to pull apart setting close to fault scarps. Very coarse-grained and immature breccias have generally been attributed to the Mitu in this region although they might very well represent a local subfacies of the Sarayaquillo when close to Jurassic basin boundary faults. Pucará Group The Pucará overall, represents the maximum flooding event of a major megasequence with the Chambara and lower Aramachay Formations forming the lower transgressive cycle and the upper Aramachay and Condorsinga/Sarayaquillo Formations forming the upper regressive cycle. The Condorsinga Formation is overlain conformably by the newly defined (Advantage, 2001), predominantly evaporitic, Callanayacu Formation or by red beds of the Sarayaquillo Formation. In the Ucayali Basin the eastern Pucará shoreline has a N–S trend from approximately just west of the Contaya Arch to the Agua Caliente field north of the Shira Mountains, with the hinterland being located to the east. As interpreted by some, the Pucará depression was a restricted basin partially isolated from the open sea by early positive movement on the NW–SE trending proto-Marañon high that acted as a subtle barrier during basin development. An alternative explanation and the one supported by the various PARSEP studies, is that the ‘basin’ was segmented into a series of smaller wrench related restrictive depocenters and that a good percentage of the deposited evaporites were the result of sabkha deposition. Excellent examples of pre-existing structural features controlling depositional patterns and facies distributions of Pucará were presented by PARSEP (2002) in the Shanusi 1X well. The distribution of the Pucará Group is restricted to subsurface occurrences in the northwest and western portions of the Ucayali Basin, and in outcrops in the Fold Thrust Belt. The Pucará as seen in outcrop, is a marine sequence that changes to a continental facies and pinches out in its eastern occurrences. The exception to this is the Aramachay Formation of the Pucará Group which maintains its marine organicrich character in the San Alejandro 1X and Agua Caliente 31D-1X wells as shown in stratigraphic cross-Sections 3 and 7 (Appendix 2c and 2g). The Condorsinga Formation of the upper Pucará Group was penetrated by the San Alejandro 1X and

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was found to be a siliciclastic rich unit resting on the Aramachay Formation, which in turn unconformably overlies the Copacabana Group. The Chambara Formation, of the lower Pucará Group, pinches out to the west of the San Alejandro 1X well. In the northeastern Ucayali Basin, the Pucará Group is recognized in the subsurface as in the Huaya 3X well, as mainly a siliciclastic unit. The Pucará section intersected in the Huaya 3X well is a red and brown red sequence of interbedded mudstone, siltstone and sandstones. The mudstones are found in laminated beds, and the sandstones as fine to very fine, occasionally medium-grained, and subangular with argillaceous matrix and locally calcareous. The siltstone is sandy, micaceous, and locally calcareous. A less known carbonate/evaporitic sequence is recognized in the southern Ucayali Basin in the southernmost Oxapampa wells, as shown in the stratigraphic crosssections 1, 2, 5-8 (Appendices 2a, b, e, f, g, and h). A 25m thick sandstone remnant of Rhaetian-Hetangian age was found by Shell (1997) in the Mainique Gorge and represents a unique occurrence of the Pucará Group east of the Shira Mountains. This sequence is shown on stratigraphic cross-section 9 (Appendix 2i). The Pucará has only been observed within the carbonate facies in the NW part of the Ene Basin area. The possible presence of an uppermost Pucará is also anticipated between the San Matias uplift and the Pachitea Basin, where black shales with sandy levels containing evaporitic molds (Elf, 1996), have been identified. These could represent the upper transitional facies from marine (Pucará) to continental (Sarayaquillo) deposition. How this interval correlates to the Aramachay identified in the San Alejandro well as both are described with very similar lithologies, will require further investigation. The black shales of this latter interval in the Ene Basin are barren due to overheating. These shales do, however, constitute the principal decollement level at the base of the allochtonous unit of the San Matias thrust. Elf concluded the Pucará Formation in this area records an intertonguing between internal platform carbonates and related coast sabkha facies in which an influence of siliclastic input is recorded. These observations support well, the regional analysis on the Pucará as presented in this and previous PARSEP reports. Evaporites (Salt) In the northern and central Ucayali Basin, the evaporite section is generally present only within the western areas of the Basin boundaries and can be readily identified seismically (Appendix 3c, Figure 4) and mapped (Figure 17). The greatest thicknesses are seen west of the Pisqui – Rashaya structural trend in the northern Ucayali Basin and within the disturbed belt west of the San Matias thrust where a salt section has been penetrated by the Oxapampa 7-1 well. The salt occurrences appear to be confined by a major Paleozoic northeast trending fault system with normal displacement that was associated with the breakup of the stable platform, during Mitu time. West of Rashaya Sur (Appendix 3g Figure 3) on the seismic line shown in Appendix 3g Figure 5, such a fault with normal displacement of approximately 1 second of throw can be identified with the lower Mesozoic evaporitic section being limited to the hanging wall block. It is believed that a series of isolated deep grabens were formed during Mitu time and because of their restricted nature, were conducive to the development of significant evaporite deposits. In other words, the evaporites identified in the Ucayali Basin may largely be restricted to these depocenters and

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consequently not more blanket-like in occurrence as they have been described in the previous PARSEP works (PARSEP, 2002 a, b). A further example supporting this can be documented East of the Pisqui – Rashaya structural trend, where areally small pods of evaporites can be found in isolated inverted half grabens as in the productive Aguaytia structure as shown in Figure 18.

Figure 17: Isochron Map of the salt ‘swells’ in the western Ucayali Basin. Cold colors represent thins and hot colors represent thicks.

Sarayaquillo With further regression of the Jurassic sea the Pucará Formation and evaporitic unit were overlain by Middle to Late Jurassic continental red beds of the Sarayaquillo Formation. Termination of the Sarayaquillo deposition coincides with the end of the Jurassic, which is represented by the regional Nevadan unconformity over which lies sediments of Cretaceous age.

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Aguaytia 1X

Seismic Line G31-163

Pozo Chonta Agua Caliente Base Cretaceous

TD Sarayaquillo

Salt

Pucará Copacabana Cabanillas Contaya

Figure 18: Seismic line across the Aguaytia structure showing the presence of salt (?) within an Andean inverted, early Mesozoic-aged graben.

The Sarayaquillo Formation in the Ucayali Basin is largely restricted to northern Ucayali, centered around the Contaya Arch, and in the north to central western Ucayali Basin where thick sections of the sequence can be found overlying the salt on the hanging walls of the large displacement pre-Mesozoic normal faults such as the ones described in the previous section west of Rashaya Sur (Appendix 3g Figure 3). The Sarayaquillo is virtually absent from the southern Ucayali Basin. In the Ene Basin a considerable thickness of Sarayaquillo has been identified. Although the basal contact of the Sarayaquillo with the Pucará is difficult to define in this area, the lower Sarayaquillo was described by Elf (1996) as corresponding to a lower coastal plain or lagoonal setting. The middle sequences were extremely characteristic of the unit containing 100’s of meters of conglomerate characteristic of a distal alluvial fan or braidplain progradation, while the upper, was sandier and representative of meandering channel and crevasse splay deposits corresponding to a low gradient flood plain setting. Elf also suggested that even though all conglomeritic series with oriented pebble structures were assigned to the Middle Sarayaquillo this may also be representative of a more distal facies of a Mitu Breccia facies. 4.3.2.9 Cretaceous The reader is referred to extensive and excellent studies done to date on the Cretaceous stratigraphy in the Ucayali Basin in such works as Robertson Research (RRI)’s Petroleos del Perú (1990) and Shell (1997) and in the Ene Basin, in Elf (1996b). The objective of this PARSEP study was to correlate time units across the Basin that could be tied back to seismic. The methodology to do so and the results are described in detail in the preceding section. Within the context of the regional

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stratigraphic cross-section grid and geological mapping that was done for this project, the subtle details of the Cretaceous stratigraphy that are needed to further understand its importance in defining hydrocarbon trapping geometries, were not examined. Through the length of this study, digital well data was collected to further supplement the Ucayali Basin database in preparation for such future studies. An important observation emphasized in this study is the change between the Mesozoic and late Paleozoic stratigraphy in the northern and southern Ucayali Basins and across major structural features (hingelines) that show evidence of syndepositional influences. On this later point, several notable examples of structures contemporaneous with Cretaceous sedimentation were described in both the Santiago and Marañon Basins (PARSEP, 2002). Similar observations were also made by Elf in the Ene Basin (Elf, 1996), who stated that synsedimentary block faulting is inferred in the Basin in order to explain the rapid and important thickness variations from west to east during Cretaceous time. Elf also noted (1996a) that the present day western border of the Ene Basin does not correspond to the deepest part of the Cretaceous Basin as was once thought. Rather, the basin probably thickened toward the west and may have even been even thicker yet westward of the present-day Ene Basin where it is now eroded. The Cretaceous mega-sequence covers the entire Ucayali Basin with regional thinning to the south as demonstrated in Cretaceous isopach map shown in Figure 19 and stratigraphic cross-sections 2, 4, 6 and 8. The lower Cretaceous Cushabatay and Raya Formations are seen to onlap the Cretaceous unconformity between Platanal and La Colpa wells (stratigraphic cross-section 2) and between the Runuya and Sepa wells (stratigraphic cross-section 4). The Cushabatay and Raya wedges align in a NE/SW trend as shown in the subcrop lines drawn on Figure 19. In any case, the Cushabatay and Raya Formations are present west of the N/S alignment formed by wells La Colpa 1X, Shahuinto 1X, Mashansha 1X and Sepa 1X (stratigraphic cross-section 10). The regional lithostratigraphic and biostratigraphic correlation and interpretation in these stratigraphic cross-sections extend the uppermost section of the Agua Caliente Formation to the southernmost Ucayali Basin including the Camisea area. PARSEP places the top of this formation at the top of Shell’s Basal Chonta Sandstone and, therefore, it also includes the sandstone unit of Cretaceous age designed as Upper Nia as defined by Shell (1997). Stratigraphic cross-section 10 includes twelve wells east of the Cushabatay and Raya wedges, which very clearly demonstrates the relationship between the Agua Caliente Formation in the wells and the pre-Cretaceous sequence. PARSEP’s preliminary interpretation shows the Mashansha 1X well with a very thin Agua Caliente Formation overlying the Copacabana Group. Cushabatay The Cushabatay is limited to the northern and western Ucayali Basin as noted above, and the Ene Basin. Thickness variations of the Formation range from a maximum of just over 400m in the Santa Clara 1X well of the Contaya Arch area (stratigraphic cross-section 1) to over 200m in the Ene Basin and to 0m as the formation pinches out to the south and east in the Ucayali and possibly over the central and southern Shira

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Figure 19: Isopach of the Cretaceous in the Ucayali Basin from well control with the significant pinchout (onlap) edges of the Cretaceous sequences highlighted. Note the dramatic thinning of the Cretaceous from northwest to southeast.

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Mountains (Elf, 1996b). The Formation forms a sharp-based fining upwards unit of sandstones unconformably overlying the Sarayaquillo Formation. It consists of a thick amalgamation of braided to low sinuosity channel belt sandstones. This broad, laterally continuous sand body is overlain by the marine to restricted marine shales of the Raya Formation, which end the broad transgressive trend recorded by the Cushabatay. Agua Caliente The Upper Agua Caliente is seen onlapping Paleozoic aged units in the southern Ucayali Basin as the entire Cretaceous section thins from North to South (Figure 19). In the Camisea fields, we interpret the top of this unit to be equivalent to the top of the Chonta Basal Sand of Shell nomenclature. It is found beneath a continuous shale unit that can be correlated throughout the area, although the lithostratigraphic top of this interval may in fact extend upwards into what Shell has designated the Lower Chonta interval. If so it would therefore represent the upward continuation of a predominant transgressive sequence of sandstones channels and mudstones. In the Ene Basin, Elf refers the Agua Caliente as the Iscozacin (Elf, 1996b). Here the Formation shows a shallowing upward trend toward littoral sandstones. These sandstones are interbedded within illite-dominated formations. This package is overlain by a 300m thick sequence of extremely shaly lower coastal plain facies containing minor channel and crevasse splay sands. Field observations (Elf 1996) show that the Iscozacin (Agua Caliente) acted as a decollement level with internal deformations and duplications. Chonta Overall the Chonta Formation represents the end of a regional transgression and the beginning of a regressive episode. The maximum flooding surface that occurred during Chonta deposition more or less represents the division between the Upper and Lower Chonta intervals. During the period of maximum flooding, marine conditions were prevalent throughout the entire Ucayali Basin and deposition during this time was restricted primarily to marine shales and limestones. In the Camisea area this interval has excellent seal characteristics, containing several anhydrites beds within its upper section. The Chonta thins to the east and SE towards the Basin borders (stratigraphic crosssections 4 and 8) and it reaches a minimum drilled thickness of 150m. In the easternmost well in the Basin, Panguana 1X, the Chonta has still maintained a high shale content which comprises approximately 50% the section (stratigraphic crosssections 2 and 9) which is probably sufficient for it to maintain reasonable sealing characteristics. The Chonta Formation in the Ene Basin is made up of a thick (500-700m) thinly bedded carbonate mudstone accumulation. It is clearly transgressive on the top of the Agua Caliente with a backstepping of a siliciclastic dominate shelf, followed by an aggradation of marine carbonate platform interrupted by a regressive event and finally

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a regressive siliciclastic dominated shelf, which is cut at its top by a major unconformity. Vivian Formation The nearshore regionally extensive Vivian sandstone complex is subdivided into 3 units, with the two sand sequences, the Upper and Lower Vivian being separated by the Cachiyacu interval. The sands are quartz arenites, white, very fine to very coarse -grained, poorly cemented with quartz overgrowths, and moderate to good intergranular porosity. The Upper Vivian typically has kaolinitic authigenic clays while the Lower Vivian sandstone as noted primarily in the southern Ucayali Basin, has a much cleaner sand character. Channel sandstones develop in the base of both sandstone units and rest on erosive contacts over their respective lower mudstones units. The Cachiyacu represents the end of a transgressional cycle (fining upward sequence) that begins with deposition of the Lower Sand. The Cachiyacu cycle represents a period of considerable stratigraphic variability as it contain numerous shales and discontinuous sands that have remained protected from fresh water flushing which is more common than not in the Vivian section throughout the Basin. The Vivian in the Ene Basin is found overlying the Chonta, separated by a significant erosional unconformity and consists of channel sands that grade upward into a lower coastal plain facies. These lower sandstones have been designated as the Lower Vivian sandstone. The coastal plain interval shows an overall increase in marine influences and is eventually overlain by a shoreface sandstone termed the Upper Vivian. After a brief period of emersion there is further marine influence with the deposition of marls and carbonated sandstones to sandy limestones, which is what has been designated as the Cachiyacu by Elf (1996b). This is different from the interpretation of PARSEP who regionally have called the interbedded shale package between the Upper and Lower Vivian the Cachiyacu. 4.3.2.10 Tertiary The Tertiary section consists of a wedge shape foredeep deposit of red bed cycles, with poor hydrocarbon potential that is widely distributed throughout the Basin overlying sediments of Cretaceous age. Paleocene aged sediments are normally described overlying the Vivian Formation. Elf (1996b) has the ‘Cachiyacu’ in the Ene Basin as being overlain conformably by a regressive succession of lagoonal to continental shale facies. The transition from the ‘Cachiyacu’ is gradual, through a rapid increase in reddened intervals until a there is a total disappearance of any gray facies. As a consequence the boundary between the ‘Cachiyacu’ and the ‘Tertiary’ sediments cannot be defined precisely as this facies boundary is probably somewhat diachronous (Elf 1996b). The sediments of Tertiary age consist of Paleocene/Pliocene Upper and Lower Red Bed sequences separated by the Pozo Shale and Pozo Sand. The Pozo shale/Pozo Sandstone couplet form one the strongest seismic events in the Marañon Basin and can be mapped into the northern Ucayali Basin. This event represents a regional marine incursion in the northern Sub-Andean basins and is coincidental in time with important events of hydrocarbon generation. The Upper Red Bed unit includes the Ipururo and Chambira Formations. In the south Ucayali Basin the Tertiary sediments

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consist of an Upper Red Bed Member of red and red brown sandy and silty clays interbedded with pale gray clays with sandstone units up to 15m thick and conglomerates, truncated at an angular unconformity by river deposits. This unit is underlain by a Conglomerate Member of Miocene age consisting of a thick sequence of numerous channel conglomerates with well rounded mainly Paleozoic clasts, sandstones, clays and coaly and silicified tree fragments. An underlying Sandstone Member forms a coarsening upward sequence of gray and yellow lithic channeled sandstones interbedded with red and brown clays. As mentioned previously, the Pozo Shale and Pozo Sand units are identifiable only in the northern Ucayali Basin although time equivalent markers can be mapped further south of this limit. The Pozo Shale consists of olive green claystone resting on the Pozo Sandstone made up of greenish gray sandstones, fine grained, silty, friable, tuffaceous, micaceous and carbonaceous. The Yahuarango or Lower Red Bed Member of Paleocene age is made up of red and purple clays with nodular carbonate rich layers and contains Paleocene charofites in the Camisea area. Lithic sandstone beds become more common upwards and it grades transitionally into the Sandstone Member. Red brown and green siltstone and mudstone are common in the northern portion of the Basin. 4.3.3 Structural Analysis of the Ucayali/Ene Area The tectonic history of the Ucayali Basin is complex with the most significant events spanning a period ranging from the Devonian to late Tertiary. This was discussed in a preceding section (4.2 Regional Geology). Through this complex evolution a number of prominent tectonic features were developed that give the Basin it’s present geometry as well as having influenced sedimentation at various stages of Basin development. This section of the report will focus on those elements that could be documented and studied with the data at hand, which are listed below. 1. 2. 3. 4. 5. 6. 7.

Devonian Faults Late Paleozoic Faults (Mitu rifting) and Associated Structures Late Andean Faults (Quechua III) and Associated Structures Cushabatay High Contaya Arch Shira Mountains Fold and thrust belt of the Ene and western Ucayali Basin a. North and Central Areas b. Oxapampa and Ene Basin Areas c. Camisea Area

In this analysis of the Ucayali Basin a series of six structural profiles across the Basin were constructed and are presented as Enclosures 3a to 3f on which many of the above features can be observed. A brief description on these profiles is presented in the section following this one.

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4.3.3.1 Devonian Faults Within the Ucayali Basin, Devonian faulting was only really observed in the southern sector of the Basin. Two ages of faulting can clearly be documented. The earliest represents a series of extensional faults that created deep half grabens during the Devonian (and possibly earlier) that contain significant thickness of preCarboniferous sediments. This is best seen on the seismic line displayed in Figure 5. Additionally, the Devonian to Basement Isochron shown in Enclosure 5h, clearly maps the areas of Devonian graben development within the southern Ucayali foreland. Three very significant features, all with a north-south alignment can be seen in the area between the Mashansha and Panguana wells. It is possible that these depressions may be local source kitchens containing organically rich Cabanillas Shales but further work will be required to confirm this as a possibility. The second fault type (Figure 6) is in response to the Eo-Hercynean compression in the Late Devonian, which resulted in a major unconformity separating sediments of Devonian and Carboniferous age. This compressional event as supported by some, produced a swarm of north–south oriented faults that established the structural grain of the weakness in the basement of the Ucayali Basin (Anadarko, 1999). In the preceding paragraph, however evidence is stated that this north-south trend may have been established well before the Eo-Hercynean compression and what has been interpreted as a result of this later tectonism, is just a reactivation of an older fault set. 4.3.3.2 Late Paleozoic Faults/Structures Almost the entire Ucayali Basin shows remnants of the late Permian extensional event. Similar Paleozoic block faulting and preservation was observed to the north in the SE Marañon Basin (PARSEP, 2002b). This tectonic event is one of the most significant events that happened in the Ucayali Basin and is particularly important when viewed from a hydrocarbon exploration perspective. The reasons for this are the following: 1. Many of the major structural features in the Ucayali Basin such as the Contaya Arch and Shira Mountains owe their ancestral history to the late Permian extension as they were initiated as significant horst blocks during this time. - Early structural growth allows for the capture and containment of earlier migrating oil, as structures with just an Andean history, do not. 2. Within the graben areas, thick sequences of Carboniferous to late Permian sediments containing source rock and reservoir sequences were protected from later peneplation by early Cretaceous erosion. 3. Regionally low areas and isolated grabens that were areas of lower Mesozoic sedimentation and preservation were created. Included in this would be thick salt sequences within lower Mesozoic restricted basins, and the deposition of the Pucará Group, which is considered to be the principal source rock in the northern Ucayali. 4. Development of subtle highs and lows that have influenced deposition environments and hence, reservoir development. The best example of this is within the Pucará section as intersected by the Shanusi 1X well in the Southern Marañon Basin (PARSEP, 2002a). An example similar to this is presented in Section 7.3.2.1

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Orientation of the late Permian faults generally appears to be in a northerly direction with a tendency to favor a NNE orientation, i.e. Aguaytia. Features such as the Contaya Arch and the Shira Mountains, which were supposedly to have been initiated as horsts during this time, have a more of a NNW (Shira) and NW (Contaya) orientation but this may be reflecting more of a later superimposed Andean imprint. Very often these late Permian faults were reactived during the Andean Orogeny as inversion features such as Aguaytia, or through a further accentuation of the older high block. However, in many instances as seen in the figures shown within Appendix 3h (Rashaya Sur), there is little to no reactivation. The Coninca-Pisqui Anticlinal trend is a good example where the older NNW trending faults show little reactivation and, where they do, it is only in a strike-slip manner, where they act as relays between NW trending en echelon Andean faults (Appendix 3h). 4.3.3.3 Late Andean Foreland Faults/Structures Generally speaking the late Andean aged faults of the Ucayali Basin and their associated structures, are well documented. They often have a strong surface expression, can be readily mapped seismically with most seismic programs having been designed to better define these features, and finally, it is the Andean aged structures on which almost all of the wells in the Basin have been drilled. In the northern Ucayali Basin, several very prominent structural trends exist that are generally just a result of Late Andean tectonics. The first is the Pisqui – Coninca – Rashaya Sur trend near the eastern border of the Basin, and the second is the Maquia – Cashiboya trend near the eastern border. Both have the very distinctive NW Andean orientation, and, as yet, production has been established only on the Maquia – Cashiboya trend. In the southern Ucayli Basin the most significant pure Andean aged structure is Sepa, which was drilled by Shell in the 1980’s. The only other structure comparable in size in the foreland Basins of Peru would be the Loreto Structure of the southern Marañon Basin. Many other Andean aged features such as Aguaytia, the Tamaya – Rio Caco trend, in the central Marañon, and the large mega-structures such as the Shira Mountains and the Contaya arch are also present, but they are largely reactivations of older structures. 4.3.3.4 Cushabatay High The Cushabatay High is a very prominent structural feature with Jurassic Sarayaquillo exposed on the surface, bordering the northern Ucayali Basin (Enclosure 2a). The interpretation of PARSEP (2002a) has the Cushabatay High as very a significant half graben filled with sediments of Pucará and Mitu age that developed concomitantly with the NW – SE trending horsts and grabens seen in the foreland of the Marañon Basin in response to the Permo-Triassic extensional event. The Cushabatay graben was filled with a very thick succession of Mitu overlain by Pucará, Sarayaquillo and Cretaceous sediments that was later inverted some time between the latest-most 52

Figure 20: Seismic Profile 3 from PARSEP (2002a), extending from the Huallaga Basin (left) to the Ucayali Basin (right) showing the interpreted inverted nature of the Cushabatay High, late Permianearly Triassic half graben.

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Cretaceous and pre-Chazuta/Shanusi thrusting in the late Tertiary of the southern Marañon Basin (Figure 20). As this structure was in place prior to the forward-most advancement of the fold and thrust belt, it acted as a buttress to any further eastward advancement of the FTB into the Basin in much the same manner as the Tiraco Dome to its north and Shira Mountains to its south. 4.3.3.5 Contaya Arch The Contaya Arch is a roughly N-S trending structure that represents the northeastern limit of the Ucayali Basin, separating it from the southern Marañon Basin (Enclosure 2a). The Contaya Arch has typically been called an ancestral horsted structure with its origins beginning in the Permo-Triassic and Jurassic, then uplifted by compression in the Neogene (SPT, 1993). Some have postulated that it may have even originated as early as the Devonian (SPT, 1993). Whether this is the origin of the Contaya arch or it is a product of a late Cretaceous-early Triassic inversion as interpreted for the Cushabatay High, or a product of continued wrenching along the proposed NE trending Contaya Shear zone, which separates the Marañon and Ucayali Basins as proposed by Tankard (2001), is a subject for future debates. 4.3.3.6 Shira Mountains The Shira Mountains and their subsurface extension to the north is perhaps the most prominent tectonic element in the Ucayali. On the surface, this feature trends NNW/SSE from the central north Ucayali down south, to the west of the Camisea area. Its subsurface extension to the north extends into the Cashiboya/Maquia and Contaya Arch areas following the surface Ucayali River alignment. This regional structural alignment coincides with the Sarayaquillo and Pucará eastern wedges that divides the Ucayali Basin into a deep western basin with a thick sedimentary section containing a thick early Mesozoic section, and a shallower eastern basin where the Cretaceous is found directly overlying the Paleozoic. On the surface, the Shira Mountains divide the southern basin into a larger eastern portion, and a western portion that includes the Oxapampa/Ene fold and thrust belt and the Pachitea sub-basin. Some of the initial geological maps available prior to the 1996 field work done by Elf along the west central Shira uplift, indicated that all the Mesozoic series was present but reduced in thickness. Field data along seismic lines 96-ENE-03, 5, 7 and 9 (Enclosures 2c) indicate that only Upper Cretaceous (Cachiyacu, Vivian) is present, which in turn is found resting unconformably on the Permo-Carboniferous series (Ambo, Tarma, Copacabana). The Ene Formation was not identified. These observations were supported by gravity data, which suggests that the crystalline basement is shallower in the Shira uplift and that the overlying sedimentary cover is thinner than in the surrounding area (Elf, 1996) In summary the Shira Mountains are interpreted to be an ancestral horst block formed during late Permian time (Mitu rifting) and is found to have the latest Cretaceous sediments overlying rocks of Paleozoic age. This would imply either:

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1. A late onlap of the Cretaceous onto a Paleozoic high that had remained emergent through most of the Mesozoic, or; 2. A major erosion of most of the Cretaceous during the Peruvian tectonic phase. The final event affecting the Shira Mountains was the significant uplift that occurred in later Neogene which elevated the mountains to a considerable height. Of importance are the observations that the Shira Mountains are seen cutting the western Ucayali FTB into two discontinuous segments, and is clearly seen to be acting as a buttress to any further eastward advancement of the Oxapampa/Ene FTB. It would therefore seems safe to conclude that there was significant uplift in the Tertiary of Shira Mountains in an event or series of events that pre-date the latest deformation seen in the Oxapampa/Ene and Camisea FTB’s (Figure 22). This is similar to what has been suggested for the Cushabatay High as well (PARSEP, 2002a) 4.3.3.7 Fold and thrust belt of the Ene and western Ucayali Basin North and Central Areas The fold and thrust belt of the northern Ucayali begins with the Chazuta thrust located to the west of the Cushabatay High, which continues south and is found separating the Huallaga Basin from the Ucayali Basin. From previous studies (PARSEP 2002), it was determined that the movement on Chazuta Thrust represents approximately 45km of horizontal shortening. The Chazuta thrust is controlled by seismic in the Huallaga Basin (PARSEP 2002a) but there is little subsurface control south of this area and published quadrangle maps of Ingemmet (Appendix 2a and 2b) were utilized for the following interpretation. At approximately the westernmost point of seismic line CP739802 (Appendix 2a) the thrust belt is offset to the east by what is interpreted to be a northwest trending lateral ramp after which the fold belt trends almost north to south to near the Oxapampa Area (Appendix 2a and 2d). The interpretation of the thrust front from the Ingemmet data in the northern Ucayali is shown on Enclosures 3a to 3d. Structural Section A (Enclosure 3a) shows a west verging fault detaching at depth into a east verging blind thrust. Structural Sections B and C (Enclosures 3b and 3c) show an east verging thrust front with overturned beds and the southernmost line Section D, is depicted simply as an east verging thrust. Oxapampa and Ene Basin Areas The delineation of the Oxapampa/Ene fold and thrust segment is depicted in Figure 2. The northern edge of this segment is also offset to the east by another interpreted lateral ramp, which is similar to what was seen within the northern segment. The eastward leading edge of the Oxapampa/Ene segment is defined by the San Matias Fault, which trend roughly NNW, separating the fold and thrust belt from a sliver of the west central Ucayali Basin, often referred to as the Pachitea Basin. This in turn terminates into an older basement cored uplift trending North, the Shira Mountains, where the thrust belt collides with the Shira Mountains, south of the Oxapampa wells. The area South of this is what has been historically referred to as the Ene Basin.

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Figure 21: Map of the Shira Mountains (Pajonal High), Pachitea Basin and the Oxapamapa and Ene Basin Fold and thrust Belt showing the major tectonic features (after Elf, 1996a). Elf has divided the Ene Basin into three regions, the northern, central and southern Ene Basins

The Ene Basin has been designated as a basin largely due the presence of Tertiary aged sediments. These sediments, however, are nothing more than the preservation of younger sediments within the intervening lows between thrust sheets south (Figure 22) as the older sediments are progressively found at increasing depths from north to south. Two structural profiles are shown through this thrust belt segment.. The first is Section E (Enclosure 3e), which goes through the Oxapampa 7-1 well, the San Matias Thrust, the Pachitea Basin and into the Shira Mountains. The interpretation presented here is different than the one made by Elf (1996c). PARSEP has interpreted two major thrusts versus one by Elf, with a detachment surface somewhere near the base of salt and Mitu levels. The reason for this was that two salt bodies at different levels were interpreted in the seismic line Elf96-12, and as depicted in Structural Section E, the only way to allow this was with the repeat of a Mitu/Salt/Pucará succession.

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Figure 22: Structural profile through the central Ene Basin modeled from the interpretation of seismic line Elf96-09 (after Elf, 1996c). In this region, the principal detachment surface and zone of multiple imbrications, is interpreted to be within the Cabanillas Formation. The Elf interpretation has the western margin of the Shira Mountains as an ‘old’ high controlled by a series of down to the west normal faults of substantial displacement that acted as a buttress to eastern the advancing thrust front.

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The second profile, Structural Section G, (Figure 22) is taken from Elf’s interpretation of Elf96-09 in the central Ene Basin. At this point it should be noted that the SEGY data set provided to PARSEP through the Ene Basin was an earlier processed version with much poorer reflector continuity in the structurally complex areas than the one used by Elf in their final interpretation. Consequently, this report relies heavily upon Elf’s interpretation within the Ene Basin Area. This profile shows the principal detachment surface of the Ene thrusting to be within the Cabanillas Formation, which is also depicted as a zone containing multiple imbrications.

Figure 23: Magnetic Map (reduced to pole total field) of the Ene Basin showing the contrast in magnetic characteristics been the northern Ene Basin and the Central and Southern Basins across the Tambo Fault zone.

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Figure 24: Evolution of the of the Tambo Fault zone (After Elf, 1996a) – Two alternative explanations with the inactive paleogeographic limit scenario being favored.

The interpretation of the eastern boundary of the Ene Basin and its relationship with the Shira Mountains remains controversial. Field data in the area indicate the presence of numerous diffuse extensional criteria (several observed normal faults and sinistral wrench movements along the Tambo Fault zone direction). The chronology of these two events has not been established. Field data confirms the seismic interpretation of Tertiary series against relatively none-deformed Paleozoic formations of the Shira’s (Elf 1996c). This interpretation fits well the regional interpretation of PARSEP in this and its preceeding studies (PARSEP, 2002a and b). If the north trending Shira Mountains are controlled by a series of down to the west normal faults of substantial displacement, this trend of older normal faults is probably contemporaneous with Mitu deposition, and would parallel and be generically related to the major pre-Mesozoic normal faults in the north to central western Ucayali and the east central Ucayali as discussed in a previous section (4.3.3.2). In many ways the Shira Mountains are acting in much the same manner as the Tiraco Dome and Cushabatay Mountains to the north (PARSEP, 2002a) where they are older emplaced highs acting as a buttress to the eastward advancement of the fold and thrust belt. Elf in their evaluation of Block 66 divided the Ene Basin into three regions, the northern, central and southern basins (Figure 21). The northern Ene Basin as depicted

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by Elf (1996a) is bounded to the east by the Cordillera San Matias thrust and includes the southern Oxapampa area. Its southern margin is roughly paralleling the Tambo Fault Zone although there is no field evidence that this fault crosses through the Basin. Nevertheless the magnetic data indicates a meaningful limit between two different sectors of the Basement showing significantly different characteristics (Figure 23). This emphasizes a deep inherited tectonic element that might have influenced the paleogeography of the successive Mesozoic and Cenozoic Basins. In terms of magnetic basement, the Tambo fault zone crossed the Ene Basin and extends outside the Elf survey areas in both direction. It is associated with a major susceptibility contrast between sediments and basement suggesting the possibility of an oceanic or at least a transitional crust at depth. The Tambo Fault zone can be interpreted as an inherited non-reactivated structure or as an active strike-slip fault during Andean compression (Figure 24). As there is no evidence of strike-slip movement or associated deformation (fold axis deflection) west of the Tambo Fault Zone, it appears more as a passive limit between the Basin and a basement high. Present day seismicity in the area also suggests that it is an almost inactive entity (Figure 25). Elf proposes that the Shira Mountains acted as a buttress and the observed en-echelon anticlines pattern in the Basin could be associated to the influence of this rigid area. The tectonic evolution of this zone in this later case is shown in Figure 24.

Figure 25: Location of present day seismicity in the Ene Basin and surrounding area (from Elf, 1996c).

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The central Ene sub-basin (Figure 21 and 22) is occupied by a huge Tertiary syncline whose syncline axis crossed across the boundary (Tambo Fault Zone) into the northern sub-basin without displaying any evidence of a change of direction or displacement. The boundary with the southern basin has been interpreted from gravimetric data which indicates a roughly N-W step. As the northern sub-basin, it also is affected by important active seismicity (Figure 25). The southern Ene sub-basin from remote sensing and gravimetric analysis shows significant differences with other parts of the Ene Basin. Surface structures appear to be more continuous. The amount of deformation appears less important and the wavelength of the structures is larger. The basement is apparently shallower than in the northern and central sub-basins and the seismicity of the area (Figure 25) shows strong discrepancies between the North and Central sub-basins that could reveal a change in decollement level and consequently a major change in the paleogeographic environment (Elf, 1996c). Camisea Area The Camisea area has been the focus of attention for a large number of years with the discovery of the giant San Martin and Cashiriari and the smaller Mipaya gas/condensate fields in the 1980’s, and the Pagoreni in the 1990’s, in the thrust and fold belt of the southern Ucayali Basin. Consequently, much effort has gone into the structural interpretation of the extensive data in this area by such companies as Shell and Chevron. PARSEP due to time constraints and a limited seismic data set of varying quality (see Section 5.0 on Geophysics) could never duplicate the excellent work done in this region, especially by Shell. Additionally, with the recent acquisition of a large 3D program over the Camisea Fields by Pluspetrol that may ultimately redefine the geology of this area or at least in all certainty, refine it, the PARSEP Group largely reviewed this area in order to incorporate it into the regional context of the Ucayali/Ene Basin evaluation. The remainder of this section on the Camisea area will be to highlight a number of observations that impact regional tectonic trends rather than a discussion on the detailed structural interpretation of this complex area. Structural Section F (Enclosure 3f) is the one exception to this, which traverses the southern Basin tying outcrop, seismic and well data. This section depicts the fold and thrust belt from the Paleozoic trusted region of the southern Camisea area, across the San Martin structure and into the Basin. Section F shows that the anticlinal structures of the Camisea area are typically ramp fault bend folds with the principal detachment surface being contained within the Ambo/Devonian section. In work that was done subsequent to this section, the Ambo is seen to thin dramatically after the termination of the eastern-most thrust. This being the case, it would appear that the forward advancement of the thrust front was controlled by a depositional hingeline within the Ambo that probably had a tectonic origin (Figure 9). The Camisea fold belt is separated from the northern segments of the western fold belt by the Shira Mountains, a positive tectonic feature that pre-dates the Camisea thrusting (Figure 2). The termination of the fold belt against the Shira Mountains is through a gradual diminishing of fault throw, both horizontally and vertically from east to west, which is roughly coincidental with the Tambo ‘Fault’ Zone. This

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Figure 26: Late Cretaceous – Tertiary paleogeography in which the locus of subsidence and deposition was the Marañon – Oriente basin area. co, Contaya high; cob, boundary between continental and oceanic crust; csz, Contaya shear zone; cu, Cushabatay high; Cv, Cordillera Vilcabamba range and shear zone; fc, Fitzcarrald anticline; Hu, Huallaga basin; j-n, JambeliNaranjal shear zone; MdD, Madre de Dios range; Pr, Progreso basin; s, oil seeps; Sa, Santiago basin; Ta, Talara basin; Tr, Trujillo basin; Uc, Ucayali basin; vu, Vuana fault. (after Tankard 2002).

decrease in amplitude from east to west has resulted in the development of much smaller structures such as Mipaya in the west relative to the large structures such as San Martin and Cashiriari, to the east.

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Figure 27: Series of three seismic lines aligned on the San Martin Anticline showing the northeast propogation of the thrust front into the southern Ucayali Basin from west to east.

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Tankard (2001) in his study done for PARSEP describes the Madre de Dios foldthrust belt (Camisea FTB in this study) as consisting of northward-verging, stacked thrust sheets. The western margin of the thrust belt is rotated into an arcuate string of faults against which it abuts. This arcuate string of structures is locally expressed in the northward-oriented Cordillera Vilcabamba (Figure 26) that has a discordant relationship to the overall tectonic fabric of Peru, and continues northward to form the eastern sidewall or termination of the Acre basin, and finally appears to link the Acre and Solimoes basins of Brazil. Like the Madre de Dios, the Solimoes basin also suffered structural inversion at this time. Tankard feels that the geometric relationships showing the northward-verging Madre de Dios (Camisea) fold-thrust belt was rotating into this Vilcabamba fault system, suggesting a left-lateral sense of displacement and lateral-ramp affinities (Figure 26). The Cenozoic granitoids that form the Vilcabamba Cordillera are attributed to transtensional dilation along this shear zone. This Vilcabamba shear zone accommodated structural shortening, and relayed the compressional stresses into the Solimoes basin as well. In this context, the faulted Fitzcarrald anticline (Figure 26) was formed as a lateral fold associated with transcurrent displacement along the principal Vilcabamba shear zone. Before leaving the Camisea area one further point needs to be emphasized. It was mentioned previously that the thin-skinned thrusting of the Camisea trend diminishes to the west. Conversely, to the east of San Martin and Cashiriari it increases in amplitude and steps out through a series of NNE trending lateral ramps further into the Ucayali Basin creating several additional anticlinal trends that have not yet been drilled. Three seismic lines shown in sequence in Figure 27 in the San Martin area show the Camisea FTB progressively stepping out into the southern Ucayali Basin. 4.3.3.8 Structural Profiles The structural profile study for the Ucayali Area was done to complete ‘to scale’ regional sections through the Basin utilizing all available data, which included seismic data, exploratory wells, geologic field data, and geological maps. In the construction of the profiles, where data was available, seismic was tied to the surface geology and to wells in the subsurface with synthetics. The structural cross-sections (Enclosure 3a to f) were prepared using a horizontal scale of 1: 100,000 and a vertical scale of 1:50,000. The six regional dip lines constructed for the Ucayali Basin are as follows: Section A (Enclosure 3a) FTB – Santa Clara – Orellana Area: This section shows a triangle zone developing in the eastern area of the fold thrust belt. The section extends to the northeast through the boundaries of the northern Ucayali into the southern Marañon passing first the southern subsurface projection of the Cushabatay High and then the northern subsurface projection of the Contaya Arch. Note the exceptionally thick section of Ene interpreted to be preserved within the stratigraphic section.

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Section B (Enclosure 3b) FTB – Pisqui – Cashiboya Sur Area: The western margin of the Basin is represented by a NW-SE trending NE-directed thrust with overturned beds. The profile crosses the Pisqui anticline, a NW- SE trending asymmetrical feature that is bounded to the east by a steeply west dipping, basement involved thrust fault. A thick lower Mesozoic and possibly Ene section is preserved on the west flank of the structure. After crossing a relatively untectonized section through the synclinal axis of the Basin, the profile crosses the Cashiboya Sur feature, a popup-type structure which has the Cretaceous sitting on a pre-Carboniferous section with the entire Copacabana Group having been eroded off. Section C (Enclosure 3c) FTB – Aguaytia – Moa Divisor: The western area of the cross-section through the thrust zone belt resembles that of the preceding section. In the western foreland (Figure 28), the significant structures in this section are the southern continuation of the Pisqui structure and the Aguaytia-Zorrillos feature, which is a productive gas field. The Aguaytia feature is a NE-SW trending asymmetrical anticline, bounded to the east by a steep NW dipping thrust fault. It is more than 100 km long, with steep dipping eastern flank. On the eastern edge of the section is an interesting inversion feature with a thick preserved Ene section beneath the Cretaceous. The eastern boundary of the Basin here is defined in part by the Moa uplift to the north which lies just inside, and sub parallel to, the Peruvian-Brazilian border.

Section C

Figure 28: Radar image of western regions of the Ucayali Basin crossed by Section C. Section B is located parallel to C but just off the map to the north.

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Section D (Enclosure 3d) FTB – Chio – San Alejandro – Agua Caliente – South of Moa Divisor: This section crosses several important geological features in the Ucayali Basin. They are, from west to east: 1. The east verging FTB; 2. Thick salt swells of lower Mesozoic age that trend NW (drilled by the Chio well); 3. The San Alejandro Structure; 4. The productive Agua Caliente Structure which represents the northern subsurface extension of the Shira Mountains to the south; and 5. The northern plunge of the Tamaya-Rio Caco, north to south trending anticline. The Agua Caliente anticline is a NW- SE oriented dome-like structure, bounded to the east by the westward-dipping Shira thrust; it is characterized by 20-35 E dipping horizons on the eastern flank, and by 10 W dipping horizons on the western flank. The anticline is breached and the Agua Caliente Formation crops out at the core of the anticline, and the Chonta Formation crops out on the border. West of the Agua Caliente structure there is a thick sequence of lower Mesozoic sediments preserved that thin gradually to the east. East of the Agua Caliente structure, there are none. Section E (Enclosure 3e) Oxapampa Area – Shira Mountains – NE of Mashansha: In the west, this crosssection was constructed using the ELF 12 seismic line, which is located 6 kilometers east of the Oxapampa 7-1 well. Field data indicate that Tertiary sediments outcrop along most of the line except to the east in the cordillera San Matias where the Upper Cretaceous Formations (Vivian, Cachiyacu) have been identified. East of the line, the main thrust related to the San Matias thrust comes to the surface. Seismic and the surface outcrops would suggest the presence of several thrusts in the San Matias Mountains. Several salt sections were identified at different levels on seismic that would further support the presence of several significant thrusts. The Shira Mountains are the prominent structural feature on this section, which are the topographic expression of a large asymmetrical anticline feature, found dipping ‘gradationally’ to the west and bounded by a major thrust fault system on the eastern flank, a result of later Tertiary faulting. The elevation of the Shira Mountains is over 1000 meters above sea level. Some basement outcrops can be observed in the eastern flank of the Shira anticline. Thinning of sediments from west to east indicates that the Shira Mountains have been a paleo-high during different sedimentation stages. Section F (Enclosure 3f) Camisea area – NE Panguana Area: The Camisea section crosses two different structural provinces, the highly deformed western province with multiple thin-skinned thrust faults, and the much less deformed eastern province. Deformation in the FTB gradually decreases in intensity from the southwest to the northeast. The highly

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shortened trends in the SW are almost no longer present towards the NE as the anticlines progressively plunge and loose structural relief. The frontal thrust of the FTB shown on the profile represents the San Martin Anticline on which the San Martin, Cashiriari and Pagoreni gas/condensate discoveries have been made.

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5.0 GEOPHYSICS 5.1 INTRODUCTION Seismic interpretation was carried out in two halves – North and South. Interpretation of Ucayali North was done using the WinPics interpretation software from Kernel Technologies, on a PC platform. Interpretation of Ucayali South was carried out on Schlumberger GeoQuest IESX software mounted on a Sun Workstation in a Unix environment. Prior to interpretation, however, a number of serious navigational errors with the data sets needed to be corrected. The first that needed to be done was to change the of datums from PSAD 56 to WGS 84 and the second one, to change the projection from TM to UTM. To fix the first problem the datum was changed from PSAD 56 to a WGS 84 datum using the coordinates from National Geographic Institute (IGN). The second issue was considerably more complex. This was fixed by using the points of the seismic coverage carried out by Norpac during the Petroperu’s seismic survey between 19831984, in addition to three Satellite points taken for PAN ENERGY from when they drilled the San Alejandro 1X well. Using this data the Transformation deltas (Projection differences) were calculated, and the coordinates for all the seismic surveys carried out from latest seventies to the present were standardized. The data sets used in the study and the number of lines available in each is presented in Table 1 below No

SURVEY NAME 1 AGUA CALIENTE 2 COASTAL PERU 3 DEMINEX 4 GSI 31 5 GSI 35 6 ANADARKO 7 HUAYA 80 8 HUAYA 90 9 COASTAL OIL & GAS 10 MAPPLE 11 NORPAC 12 PACAYA 13 SIGNAL 14 HISPANOIL 15 CHEVRON 16 OXY 36 17 REPSOL 18 SHELL UB 19 SHELL UBA 20 TOTAL 21 ENE

AREA

# de Líneas

NORTH UCAYALI NORTH UCAYALI NORTH UCAYALI NORTH UCAYALI NORTH UCAYALI NORTH UCAYALI NORTH UCAYALI NORTH UCAYALI NORTH UCAYALI NORTH UCAYALI NORTH UCAYALI NORTH UCAYALI NORTH UCAYALI SOUTH UCAYALI SOUTH UCAYALI SOUTH UCAYALI SOUTH UCAYALI SOUTH UCAYALI SOUTH UCAYALI SOUTH UCAYALI ENE BASIN

3 7 2 43 33 9 8 6 13 6 21 9 52 19 29 22 26 46 23 36 10

21 Table 1: Seismic surveys used in the Ucayali study

413

KM 63.53 227.66 64.37 1062.02 1243.82 630.57 132.65 73.11 377.75 75.24 446.27 87.78 1525.43 889.41 612.42 634.60 1014.23 1181.43 792.02 2321.13 300.82

13455.45

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All seismic lines, with navigation headers, have been saved in SEG-Y format on tape. The tape also includes a .txt file on the navigation information used, and the interpretations (horizons and faults) in ascii format. 5.2 DATA QUALITY The data quality in the Northern half of the study was moderate to good. The data was recorded between 1973 and 1998. Large holes in the SEGY data set unfortunately prevented the north central basinal area from being interpreted, i.e. the Tiruritan 1X area. In the Southern half, data quality varied from very good to very bad. In particular some of the Shell SHL-UBA series of lines had been processed for amplitude only, and this was the only version of these lines available. Lines that did not tie to the main data set (i.e., did not physically connect) were not used in the interpretation. None of the Hispanoil line were used in the interpretation as they are of such poor quality. Many lines had to be trace decimated on-screen to make them properly visible and interpretable. The flexibility of the software was a great advantage in giving the interpreter the advantage of changing displays quickly as needed. In summary, the variable quality of the data did give some problems, and some lines were not used in the interpretation, but on the whole interpretation was carried out successfully within the given time frame. 5.3 WELL TIES 5.3.1 Ucayali North Out of the 25 wells in the Ucayali North area, 13 reached the Paleozoic, and 3 reached Basement of which a large number were used to generate synthetic seismograms to tie to the seismic data. This was done directly in WinPics by first importing LAS files with tops, creating a synthetic, and then to exporting the synthetic into a ‘composite’ seismic line on the workstation. 5.3.2 Ucayali South Table 2 shows the wells used to tie the data and the lines to which they tied: WELL

SEISMIC LINE

SEPA 1-X MASHANSHA 1-X MIPAYA 1-X SAN MARTIN 1-X

shl-uba-01 rep35-128 shl-uba-19 shl-uba-13

SP SP 1056 SP 654 SP 1392 CDP 32585

Table 2: Wells used for synthetic seismogram ties (Ucayali South).

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Of the above wells, only the Sepa 1-x and Mashansha 1-x penetrated basement. Synthetic seismograms for the well ties were generated in the Digi-rule software system and plotted out on an HP 650 color plotter, then tied to paper plots of the seismic sections as the software did not support inputting the wells logs and generating the synthetics on screen. It is recommended that for future projects PeruPetro add this software package to the GeoQuest interpretation workstation. 5.4 HORIZONS INTERPRETED In Ucayali North, only the following horizons of the many that were interpreted, have been included as data files in this report: 1. Top Pozo (and its time equivalent) 2. Base Cretaceous 3. Salt (lower Mesozoic) 4. Copacabana 5. Contaya In the Southern half of the project, the following horizons were interpreted, and tied to the wells in Table 2: 1. Upper Cretaceous 2. Base Cretaceous 3. Tambo 4. Top Devonian 5. Basement The main faults throughout the area were interpreted and mapped, and fault boundary files generated. 5.5 MAPS PLOTTED The following maps were generated and plotted Two-way time structure maps (Ucayali North): 1. Top Pozo 2. Base Cretaceous 3. Top Copacabana 4. Top Contaya Two-way time structure maps (Ucayali South): 1. Upper Cretaceous 2. Base Cretaceous 3. Tambo 4. Top Devonian 5. Basement Isochron Maps (Ucayali North): 1. Top Pozo – Base Cretaceous 2. Base Cretaceous – Top Contaya 3. Salt Unit 70

Isochron Maps (Ucayali South): 1. Cretaceous (upper to base) 2. Upper Cretaceous to Tambo 3. Top Devonian to Basement (i.e. Palaeozoic) A word is in order in general about the mapping before discussing the individual maps. Maps for Ucayali North were generated in the WinPics interpretation system. WinPics does not allow for the honoring of fault boundaries in the contouring package. However fault boundaries are displayed on the maps and the general form of the structuring is clearly evident. Maps for Ucayali South were generated and contoured using the Schlumberger GeoQuest IESX software. The time constraints placed on this project made detailed editing of the machine-generated contouring impossible. Gridding parameters were chosen to maximize the use of the data points without in the one extreme oversmoothing of the data, or in the other extreme producing false anomalies. This meant that the program had difficulty honoring the throw across the faults. However the overall structural elements of the area are clear in the mapping. The thrust belt in the South that contains the Camisea field is very evident. Again, time constraints made it impossible to map anything other than the main faults. The Sepa structure is clearly mapped, as are the large throw thrusts seen in the west against the Shira uplift. The maps are included in the text of the report as page-sized plots, as well as enclosures. 5.5.1 General Comments Ucayali North – All mapped horizons exhibit a basic North-South trend, with shallow structuring to the North-East and South-West, separated by a low. All horizons are affected by faults trending South-East – North-West. Ucayali South – There are some comments to be made about features that are common to all the horizons above the Devonian. Along the San Martin thrust, all reflectors exhibit rollover into the various thrusts. The thrusting is very much controlled by deeper events, including older thrusting at the Devonian level that appears to have been the nucleus for younger movement. It should be noted that there are some structures still undrilled along this trend. Within the northern part of this Southern Ucayali area there are high-angle reverse faults, with fairly small throw, that are re-activations of older, normal faults marking the edges of grabens and half-grabens. The Mashansha well was drilled on the upthrown side of one of these faults. In the Mashansha area there is a marked basement graben that is the location of a large Cretaceous channel (discussed later in this report). It is evident that the location of the channel was controlled by the presence of older faulting. This zone of weakness would have been a controlling factor in the drainage system at that time. The younger,

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reverse faulting associated with the graben system affects all three of the shallower horizons. The structuring along the San Martin trend has been well documented, and is confirmed in the present study. Closed, rollover structures into the main San Martin thrust have resulted in several successful wells (Mipaya, San Martin, Pagoreni, Cashiriari). The present study identifies an undrilled structure, again a rollover into a thrust fault, to the north of the San Martin wells (seismic line SHL-UBA-22, Figure 29).

Figure 29: Seismic SHL-UBA-22 showing the San Martin structure on the South end of the line, and an un-drilled structure just over half way along the line. The two red horizons mark the Cretaceous interval. The blue pick is Top Devonian, the cyan is Basement.

5.5.2 Time Structure Maps – Ucayali North 5.5.2.1 Pozo (Figure 30, Enclosure 4a) The Pozo, a mid-tertiary sand-shale unit constitutes a regional marker in the Marañon and parts of the Ucayali. Although the Pozo is know geologically to be present only in the northern most portion of the Ucayali Basin, there were good reflectors in time equivalent positions that allow the extrapolation of the horizon further south to facilitate mapping. The map shows a deep depression separating the NW-SE trending reverse fault systems. Two large anomalies are mapped: one between Rio Caco and Runuya, with a structural closure of 100ms over an area of 15x7km; and one in just to the north of Rashaya Sur, also with a closure of 100ms.

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Figure 30: Pozo Time Structure, Ucayali North. Figure 31: Base Cretaceous Time Structure, Ucayali North. Figure 32: Copacabana Time Structure, Ucayali North. Figure 33: Contaya Time Structure, Ucayali North. Figure 34: Pozo-Base Cretaceous Isochron (Ucayali North) Figure 35: Base Cretaceous – Contaya Isochron (Ucayali North)

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5.5.2.2 Base Cretaceous (Figure 31, Enclosure 4b) The Base Cretaceous is an unconformity that is easily recognizable on seismic data throughout the whole of the Ucayali Basin. It exhibits many of the same features as the younger Pozo formation, with the same closed structuring. 5.5.2.3 Copacabana (Figure 32, Enclosure 4c) The limited extent of the Copacabana, as seen on the map shown in Figure 32 is a result of extensive erosion of this once massive shelf carbonate (compare with the Tambo maps for Ucayali South, where there is a marked erosional edge on the East of the map area). The Copacabana shows an important structural closure in the Southern portion of the Rio Caco area. 5.5.2.4 Contaya (Figure 33, Enclosure 4d) Deposits of the Contaya are restricted to the Eastern part of the basin. This nearBasement pick has depths of up to 5300ms two-way time 5.5.3 Isochron Maps – Ucayali North 5.5.3.1 Pozo to Base Cretaceous (Figure 34, Enclosure 4e). This map shows that the Cretaceous thickens dramatically from South to North. Thickness varies from 400ms to 1000ms (two way-way time). 5.5.3.2 Base Cretaceous – Contaya Isochron (Figure 35, Enclosure 4f) This map also demonstrates a dramatic thickening from South to North. It indicates a Palaeo structural high in the Rashaya structure, with structural closure of more than 100ms. There is also an ancient depression running through the center of the Aguaytia structure that testifies to its Andean inversion. In this sense the Aguaytia anomaly is rather unique as demonstrated by this map. As this is the only productive anticline in this immediate area, there may be some relationship between the two. 5.5.3.3 Salt Isochron (Figure 17, Enclosure 4g) The map in Figure 17 (shown in a previous section) shows the distribution of the evaporitic unit within the Jurassic section in this part of the Ucayali Basin. The salt does not extend into the Southern part of the Basin, and is confined to the eastern part of Ucayali North. As can be seen on the map, there is a particularly thick lens, trending almost due North-South in the center of the map area, to the west of the Chio well.

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5.5.4 Time Structures Maps – Ucayali South 5.5.4.1 Upper Cretaceous (Figure 36, Enclosure 5a) This horizon, picked as near Vivian on the well ties, is a fairly good reflector and can be picked easily throughout the survey area. It is highly structured in the Mipaya/San Martin area where it is heavily fault controlled. Mapping shows good rollover into the faults in this area. There is considerable closure over the Sepa structure as well. The Upper Cretaceous shallows to the East of the study area, over an extensive basement high. This horizon is uplifted to near surface near the Shira Mountains to the west.

Figure 36: Upper Cretaceous Time Structure, Ucayali South.

5.5.4.2 Base Cretaceous (Figure 37, Enclosure 5b) The base Cretaceous is a marked and familiar unconformity throughout the area and is a good pick to follow. Its form mirrors the Upper Cretaceous in many respects, except for a feature just east of the Mashansha well, where the surface is eroded by a channel feature that has not been interpreted as such in any previous work. This channel feature is discussed in detail later. This horizon also shows good rollover into the San Martin fault, and has large areal closure on the Sepa structure. It is generally flat and featureless to the East over the basement high.

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Figure 37: Base Cretaceous Structure Time, Ucayali South.

5.5.4.3 Tarma (Figure 38, Enclosure 5c) This reflector was more difficult to pick throughout the area, as it does not appear to have as strong a reflection coefficient as the others. However it was possible to follow it through most of the area. In map form it has much the same characteristics of the other, younger horizons. There is closure over the Sepa structure, and rollover into the main San Martin fault. The Tambo thins and subcrops on the Eastern side of the project area. 5.5.4.4 Top Devonian (Figure 39, Enclosure 5d) This is the nearest horizon to basement picked in the present interpretation and is largely controlled by the basement structuring. Along the San Martin thrust belt, the Devonian is displaced a small amount by an old, nearly horizontal thrust. This displacement on the Devonian appears to control the movement of the main San Martin Thrust – the Devonian (+ Ambo) surface may well be the decollement for the younger thrusting. This reflector is uplifted (along with the others) in the main thrust zone to the West against the Shira uplift. In the Northern part of the South Ucayali study area, the Devonian is faulted by the younger rejuvenated reverse faults over Basement grabens and half grabens, including the graben controlling the channel feature mentioned earlier, and discussed in detail later.

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Figure 38: Tarma Time Structure, Ucayali South.

Figure 39: Top Devonian Time Structure, Ucayali South.

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5.5.4.5 Basement (Figure 40, Enclosure 5e) Interpretation of the basement was tied to the two basement penetrations - wells Sepa 1X and Mashansha 1X. The Sepa structure is controlled by a broad basement dome, clearly seen on seismic and on the time structure map (Enclosure 5e) In the northern part of this portion of the Ucayali study, this is a well-defined reflector that becomes steadily shallower to the East until the Basement pick and top Devonian become almost one and the same. Block faulting of the basement controls much of the overlying structuring in the north and east of this area; to the south, the San Martin thrust is in part controlled by deeper, older thrusting that affects the basement morphology. The San Martin thrust provides the structuring for the Camesea gas field, well documented by the Chevron and Shell work. To the northern part of the South Ucayali study area, basement faulting along grabens and half grabens controls younger, rejuvenated near-vertical reverse faults.

Figure 40: Basement Time Structure, Ucayali South.

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5.5.5 Isochron Maps – Ucayali South 5.5.5.1 Cretaceous Isochron (Upper to Base) (Figure 41, Enclosure 5f) The main feature on this map is the thickening seen along the major channel feature, from North to South. It would appear that there is a major depositional feature in this part of the Basin. Further study of this feature is recommended as a possible new play type is involved here.

Figure 41: Cretaceous Isochron, Ucayali South.

5.5.5.2 Upper Cretaceous – Tarma Isochron (Figure 42, Enclosure 5g) This map indicates that the Isochron interval generally thins to the North-East, as the Tarma becomes thinner and eventually pinches out along a line running generally NW-SE. There is a very thick unit in the Southwest. 5.5.5.3 Lower Paleozoic (Devonian-Basement) Isochron (Figure 43, Enclosure 5h) This is possibly the most interesting and significant map of the present interpretation. On it can be seen the following features: • The graben system controlling the channel feature in the middle of the Northern part of the Southern Ucayali study area. • A major half-graben feature in the Western part of the study area. • The major thickening of the unit in the South-West portion of the study area.

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Figure 42: Upper Cretaceous – Tarma Isochron, Ucayali South.

Figure 43: Lower Paleozoic Isochron, Ucayali South.

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5.5.6 Cretaceous Channel Play – Ucayali South Historically in the Ucayali Basin, as the in the Marañon to the north, exploration has targeted young structures controlled by older, deeper structures. Stratigraphic mechanisms have been largely ignored. Future work in the Basin must include a proper study of the sequence stratigraphy and seismic stratigraphy. There is a stratigraphic feature in the survey area, shown in Figure 44 (a plot of a portion of three parallel lines over the feature in question) that has been known for some time but never examined in close detail before. Close examination of this anomaly would seem to indicate that it is a large channel that has filled a tectonic depression within the Paleozoic at this location. Interpretation and mapping shows that this was most likely part of a deltaic system, sourced from the north, depositing into a depocenter to the south (Figure 45). The channel gradually thins to the north, pinching out and providing closure of the channel sands in that direction. There is some evidence of high amplitudes within the channel so that this may well provide a new, stratigraphic trapping mechanism within the study area. The position of the channel is to a certain extent controlled by a deep basement half graben; the fault on the east side of the graben was obviously the zone of weakness controlling the drainage system in the Cretaceous and later. Future work should include sequence stratigraphy in this area to try and understand the possible provenance of the sands and their depositional environment. The present study does not afford the luxury of the time necessary to do such a detailed study of this one area.

Figure 44: Seismic Lines rep35-124, 126 and 128 (top to bottom), over the channel feature discussed in the text. Note the high amplitude event in the middle of the channel on line 126.

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It would appear that the location of the channel is in part controlled by the presence of basement faulting which has also been re-activated later, affecting the upper Cretaceous as well. This can be seen on lines rep35-124, 126 and 128 (Figure 44)

Figure 45: Cretaceous channel Isochron, Ucayali South.

In the above figure it can be seen that the channel thickens gradually to the South, a possible depocentre at this time. The channel sands thin and pinch out to the North, giving a good chance of a major stratigraphic trap. The Mashansha well, drilled immediately West of the channel had major oil shows. The presence of hydrocarbons in the area makes the channel an interesting feature for further studies. 5.5.7 Future work to be done As has been stated previously, this study was hampered somewhat by the lack of data is certain areas, and the quality of some of the data provided. There is potential for quite a bit of more work here: • Incorporating more available data into the study area. • Reprocessing of some of the data sets to make them compatible with the data presently available. • A more detailed study of the channel with a view to drilling the first stratigraphic target in the basin. The study should include an assessment of both reservoir potential and source rock migration paths to ensure that the channel could be charged. 82

6.0 WELL SUMMARY A detailed evaluation was done in this study of the 10 wells drilled between 1990 and 2002 (Appendix 3). The intention of this work was to identify the success /failures of each to understand better how to explore for Ucayali Oil. Where possible PARSEP generated maps that were utilized from the available well and seismic data and using the interpretation provided by the operator only when sufficient data was not available. These evaluations are presented in Appendices 3a to 3j and include the wells, 1. Agua Caliente 31X 2. Cachiyacu 1X 3. Chio 1X 4. Insaya 1X 5. Mashansha 1X 6. Pagoreni 1X 7. Rashaya Sure 1X 8. Panguana 1X 9. San Alejandro 1X 10. Shahuinto 1X Additionally, because of the their importance of with respect to discovered reserves in the Ucayali Basin, the Cashiriari 1X and San Martin 1X well were also included in this appendix but more from a standpoint of reference than one of evaluation.

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7.0 PETROLEUM GEOLOGY 7.1 GEOCHEMISTRY 7.1.1 General Petroperu and a host of other exploration companies have conducted numerous geochemical studies in the Marañon and neighboring Santiago and Huallaga Basins resulting in an abundance of data. These studies include 1) regional basin studies incorporating data from wells, and outcrops along the Basin border, and 2) analyses on individual wells carried out by exploration companies as part of their routine well evaluation. The studies cover the following: complete geochemical analyses to evaluate potential source rocks; make oil-source rocks correlations; genetically classify oils; and basin modeling to establish level of maturity, hydrocarbon generation timing and alteration of the oils and location of possible hydrocarbon kitchens. For detailed coverage of these and all geochemical reports the reader is referred to a database recently completed of all original geochemical reports in the Perupetro’s technical archives. Time did not permit the PARSEP group to go into any depth and evaluate in detail the geochemistry aspects of the Ucayali Basin let alone complete a Basin Modeling evaluation as was done for the Marañon Basin (PARSEP, 2002b). As such it, it is recommended that such a study be undertaken to further understand the petroleum systems of the Ucayali Basin Unlike the Marañon Basin, with two documented source rocks, the Chonta and the Pucará, the Ucayali Basin has multiple source rocks including the Pucará, Ene, Tarma/Copacabana, Ambo and Cabanillas. Additionally most of the wells drilled in the Basin have had shows, many which have recovered high gravity crudes. Clearly hydrocarbons are being generated in great quantity in the Basin from a variety of sources. One of the objectives of this study was to identify and map seismically where potential kitchen areas for the various source rocks may reside. Several maps were completed in this respect for the Ene, Ambo, and Devonian (Cabanillas). These have been presented in Figures 12, 9 and 43 respectively. PARSEP had previously conducted a first approach of hydrocarbon generation modeling through Chem Terra Intl. Consultants CTI (2000). The study gave an insight of events as well as various parameters for refinements and data estimates for more precise future modeling. This study is included in the Appendix 4 of PARSEP (2002b) 7.1.2 Source Rocks In the Sub-Andean Basins of Peru, based on TOC and Rock-Eval data, numerous formations from Ordovician age to the Tertiary can be identified as potential source rocks in the sub-Andean Basins of Peru. They are as follows:

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Tertiary • Pozo Shale Formation with Type II Kerogen, locally developing into a Kerogen Type I may be restricted to the Santiago and the Huallaga Basins, low TOC quantities are recorded in most parts of the Marañon Basin; Cretaceous • Chonta Formation contains Type II and Type II-III Kerogens with frequent TOC concentrations in the range 2-3% in the northern and NW areas of the Marañon Basin and the Santiago Basin • Raya, Agua Caliente and Cushabatay Formations also have source characteristics, but mainly Kerogen Type III and III-II quality; Triassic/Jurassic • Pucará Group is a bituminous carbonate with interbedded organic rich shale sections and is considered the principal source rock in the southern Marañon and northern Ucayali Basins and source for the Maquia, Aguaytia and Pacaya; Paleozoic • Late Permian Ene Formation (the source of the oil in the Agua Caliente Field and the oil tested in well La Colpa 1X.). Permian source rocks are important contributors in the Madre de Dios Basin and Bolivia further to the south. In the Ene Basin excellent quality source rocks have been found within the Ene and consequently, is expected to be the principal source rock there. • Ambo/Tarma-Copacabana Formations with marine shales and carbonates in the southern portion of the Basin. The Ambo has sourced the giant gas/condensate fields of the Camisea Area. • Ordovician Contaya and Devonian Cabanillas Formations have extreme maturity and moderate present-day TOC values in the SE Marañon, and like the Permian source are important contributors in the Madre de Dios Basin and Bolivial. In summary geochemical studies by various Groups have shown that the Paleozoic in the Peruvian Sub-Andean Basins has hydrocarbon source rocks ranging in age from Devonian through Permian including the Cabanillas (Devonian), Ambo (Carboniferous), and Ene (Permian). These source beds exist primarily in the central and southern Basins of Peru. Mesozoic source beds include the Cretaceous Chonta Formation with lesser contributions from other Cretaceous intervals, and the Triassic to Jurassic Pucará Formation. The Cretaceous source rocks, however, are limited only to the northern Marañon and Santiago Basin. Of particular importance within the Mesozoic are the Pucará source rocks, which are attributed to sourcing most of the oil and gas in the Southern Marañon and Northern Ucayali Basins. 7.2 RESERVOIRS/SEALS In the Ucayali Basin, because of the much thicker section of Paleozoic rocks preserved, there are considerably more reservoirs that can be explored for than in the Marañon Basin. One of the more complete works on this topic was completed by SPT 85

(1993) in the Geology, Hydrocarbon Potential and Prospect Analysis Ucayali Basin Report for Petroperu. A good portion of the following section relies heavily on SPT’s work. SPT concluded the proven reservoirs within the Basin include the following: • Ene Formation (Lower Permian) • Cushabatay Formation (Lower Cretaceous) • Raya Formation (Upper Cretaceous) • Chonta Formation (Upper Cretaceous) • Vivian Formation (Upper Cretaceous) • Cachiyacu (Upper Cretaceous) • Casa Blanca – PARSEP Upper Vivian – (Upper Cretaceous) Subsequent to the SPT study, much analysis has gone into the stratigraphy of the Camisea area, which has also proven reservoirs in the Agua Caliente (Upper Nia), several discrete sands within Ene Interval, a lower basal sand (Ene) and an upper sand (Noipatsite) and the Lower Nia sandstone of the Manique Group (which if present is usually found in contact with the unconformably overlain Agua Caliente). Both regional and local seals are present within the Ucayali Basin. The proven regional seals are concentrated within the Cretaceous interval and include • Raya Formation (Esperanza Member, Lower Cretaceous) • Chonta Formation (Upper Cretaceous) • Cachiyacu Formation (Upper Cretaceous) • Huchpayacu Formation (Upper Cretaceous) Additional to this and again from the Camisea area would be the Permian Shinai, which is a 70-100m thick organic-rich carbonate mudstone that overlies the sandstones of the Ene Formation Although non-productive as of yet, one of the principal exploration targets in the Basin has been for the Green Sandstone, a Late Carboniferous sandstone of the Tarma Group. In the La Copla well for example, the sandstone had good SP deflection, a blocky and clean GR, and good neutron and density log response indicating 37.9m pay with 19.4% porosity. Other more speculative reservoir targets include • The deltaic sandstones of the Early Carboniferous Ambo Group sealed by intraformational shales • Intratitidal carbonates of the Pucará Group as seen in the Shanusi 1X well of the southern Marañon Basin. Anticipated seal would be the transitional sabkha evaporites separating the Pucará from the Sarayaquillo • Karsted Copacabana carbonates although seals are a problem and this is dependant upon which sediments unconformably overlie the Copacabana Mitu, Pucará, evaporites, Sarayaquillo, or Cretaceous sediments. In summary the most attractive reservoirs in the Ucayali Basin are those of the Cretaceous, Manique (Lower Nia), Ene, and Green sandstone. The Cretaceous typically has the best petrophysical qualities although it’s distribution is not uniform

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throughout the Basin. Extensive mapping of the various Cretaceous units and sand/shale ratios for each was not conducted as part of this study. The reader is referred to SPT’s excellent and complete analysis of the Cretaceous reservoirs in their 1993 study. The one issue to highlight within the Cretaceous however is with the distribution of the Cushabatay. The Cushabatay is a reservoir target in the northern Ucayali Basin but it disappears to the south and east as it onlaps the Paleozoic unconformity surface reflecting an overall thinning of the Cretaceous section. Consequently, in the southern Ucayali Basin, the basal most Cretaceous reservoir target would be the Agua Caliente sandstone as has been proven in the Camisea area. The Ene sandstone distribution is spotty and dependent upon erosional inliers, which have been outlined in Figure 12. The Green Sandstone on the other hand represents an attractive reservoir target, as it is widespread throughout a good part of the Basin. In the Ene Basin, Elf (1996) concluded that the principal reservoir target was the Cushabatay as there is little to no Vivian present. The only other potential reservoir within the Cretaceous that was noted, was a littoral sandstone attributed to the Agua Caliente that is found beneath the Chonta. A deeper possibility in the area may exist within the Ene sandstone but some analysis carried out on samples of an intra-Ene sandstone by Elf, showed a rather low reservoir potential to this formation. The porosity is low and strong silicification downgraded the permeability.

7.3 PROSPECTS/LEADS The Ucayali/Ene Basin Study was intended to be a regional work, integrating as much data as possible within the Basin to investigate whether new exploration concepts, etc., could be defined. It was not intended to be an exploration exercise where the ultimate goal is in defining drillable prospects. Ultimately however, in a study such as this, certain prospects and leads do emerge and this section is a summary of our findings. During the process of this evaluation two structural prospects and two stratigraphic leads were defined. It should be noted that there are numerous other structural leads in the Basin and these have more or less been documented in Perupetro’s “Catalogo de Prospectos No Perforados. 2001 – ITP”. The structural prospects highlighted here are done so as they were mapped in more detail, are in relatively inactive areas at the moment and show some potential. The two stratigraphic traps on the other hand are new concepts and believed to be only partially representative of what can be found when a concentrated effort in exploring for stratigraphic traps is applied. 7.3.1 Structural Prospects 7.3.1.1 Rashaya Norte Rashaya Norte (Appendix 3h, Figures 3 and 4) has been identified by several companies; the most notable in recent years was Pan Energy who had this inventoried as one of their drillable prospects. Pluspetrol also identified it in their evaluation of Rashaya Sur location, on which they eventually drilled a dry hole with oil shows. PARSEP’s interpretation of this structure is different than that of both Pan Energy and

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Pluspetrol. Pan Energy had interpreted this feature is such a way that it resembled an inverted graben with salt being present beneath the Cretaceous unconformity. Our interpretation has the structure as a Paleozoic horst block with the Cretaceous overlying Cabanillas on the crest of the structure and Copacabana on its flanks. The interpretation of Pluspetrol is different in that they have the Rashaya Sur as a much larger structure areally and vertically than the Rashaya North structure. PARSEP’s interpretation is that the Rashaya Norte is the much larger of two and consequently represents a more attractive drilling target than Rashaya Sur. The Rashaya Sur well had gas shows of C1 to C5s and fluorescence through the Raya, Cushabatay (weaker shows), and the Pumayacu. A DST of an upper Raya sand tested 0.6 BBL compeletion fluid, 16 BBL FmWtr (42,600 ppm Cl) and 39 BBL diesel and 40.6o API oil. 7.3.1.2 Rio Caco Sur The Rio Caco Sur prospect is located along the massive Runuya/Rio Caco/Tamaya anticline (Figure 46), south of the Rio Caco well, within a well defined four-way dip closure (Figure 47. Potential exists within the Cretaceous, and Paleozoic (including Ene). Shows have been encountered in the surrounding wells: • Rio Caco 1X well had good oil shows in the Raya and Cushabatay • Runuya had shows within the Paleozoic section • Tamaya 1X had good oil shows in the Cushabatay

Rio Caco Sur

Figure 46: TWT Map on Base of Cretaceous along the Runuya/Rio Caco/Tamaya anticline showing the undrilled structure remaining at Rio Caco Sur

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Pozo (Equiv.)

Ene Base Cretaceous

Copacabana

Basement

Figure 47: Seismic line W75-91 across the Rio Caco structure highlighted on the preceding Figure.

7.3.2 Stratigraphic Leads 7.3.2.1 Cushabatay South Pucará Lead (CSPL) The CSPL lead is defined primarily by one seismic line, Coastal’s CP739801 (Figure 48) shot in 1998 south of the Cushabatay High in the northern Ucayali Basin. This lead is based on the concepts developed for the Pucará as a result of the evaluation of the Shanusi 1X well as describe in PARSEP (2002a). The Shanusi well tested the Pucará on a paleo-horst block that is believed to have influenced deposition during Pucará time. In this well, gas charged porous dolomitic carbonates were encountered. It is believed that over this paleo-high, high energy carbonates were deposited that may have consisted of grainstones or possibly even ‘reefal’ type deposits that represents a porous fairway trend within the Pucará that can be explored for. Figure 48: Location of Seismic Line CP739801

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Represents approx outline of magnified sections below Pucará

Base Cretaceous

Copacabana

Base Cretaceous Pucará

Top Paleozoic

Copacabana

Base Cretaceous

Pucará Top Paleozoic Copacabana

Figure 49: Seismic line CP739801 through the CSPL lead, a Pucará play where high energy carbonates are expected to have been deposited over a Copacabana erosional high. The upper section is a time section, the middle section is flattened on the Base Cretaceous and the bottom section is flattened on the Pucará.

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Seismic line CP739801 is shown in Figure 49 in a variety of forms. The first is a time section, which shows the prominent structures in the area, two NW trending Andean aged high angle reverse faults. The CSPL lead is located between these two structures within the low. In Figure 49, the middle section is flattened on the Base Cretaceous and the bottom on the Pucará. The play is set up by an erosional high in the Paleozoic over which was deposited the Pucará with presumably high energy carbonates, creating a situation almost analogous to what was described for the Shanusi Well. This is best demonstrated on the Pucará flattening where the erosional high is seen to be coincidental with the subcrop edges of the Copacabana whose limestones would have been more resistant to erosion than the over and underlying rocks. It is also interesting to note the reflectors paralleling the Pucará within the Paleozoic section which are in high contrast to the steep east dips the sediments are know to have from seismic. Consequently, it is interesting to speculate that this perhaps represents a karstified zone within the Copacabana limestones. Seals for the play would be the more tight, basinal carbonates of the Pucará located within the depression to the east and the evaporites that are believed to separate the Pucará from the Sarayaquillo. 7.3.2.2 Mashansha Channel As this lead was covered in Section 5.5.6 it will just be summarized here. In Figure 44 (a plot of a portion of three parallel lines over the feature in question) there is a stratigraphic feature that has been interpreted to be a Cretaceous channel cutting into the Paleozoic of probable Ene and Copacabana age. Interpretation and mapping shows that it was most likely part of a deltaic system, sourced from the north, depositing into a depocentre to the south (Figure 45). The channel gradually thins to the north, pinching out and providing closure of the channel sands in that direction and thus the possibility of a major stratigraphic trap. If this channel is filled with porous sands, it may explain the lack of hydrocarbons with the Mashansha structure, as there would have been no lateral seal. Any hydrocarbons that were present in Mashansha would have leaked into the Channel and migrated elsewhere, possibility into a stratigraphic trap that lies somewhere within this Cretaceous sand body. An alternative interpretation, however is that the Cretaceous unconformity is higher than mapped and what is interpreted a Cretaceous Channel is in fact an Ene inlier beneath the unconformity.

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8.0 CONCLUSIONS The Ucayali Basin is one of several Sub Andean Basins in Peru, with mixed exploration success. The Basin is approximately 650 km long and about 250 km in width. Much of the Basin remains under-explored. This is a poly-history basin, with elements of both extensional and compressional tectonics, with older, Paleozoic faults being rejuvenated as reverse faults that have controlled much of the structuring and hence the trapping mechanisms of the Basin. The western boundary of the Basin is dominated by a thin-skinned fold and thrust belt along almost its entirety, which is interrupted only by the Shira Mountains in the southern regions of the Basin. It is within the fold and thrust belt south of the Shira Mountains that the giant Camisea fields have been discovered. Generally, the principal reservoirs in the Basin have been within the Cretaceous and the Lower Nia (Camisea) although others in the Late Carboniferous Tarma Group (Green Sandstone), and the shoreface and fluvial sandstones of the Late Permian Ene have been targeted. The later is a major contributor to the reserves of the Camisea fields The work completed in this study was an attempt to first standardize the data digital set (seismic and wells) and then to utilize the data completing a regional evaluation of the Ucayali/Ene Basin. The first part was accomplished and a digital data set is now completed and includes, 1. A tied (as well as could be) SEGY data set representing a large portion of the available seismic in the Ucayali Basin 2. Composite log LAS files for each of the exploration wells of the Ucayali Basin 3. An Access database with tops, tests, etc., of all exploration wells in the Ucayali Basin Further recommended work on this segment would be to, 1. Obtain the Oxy and Pangea seismic data sets in the areas of the La Colpa and Shahuinto wells 2. Complete the loading and tying of the Shell UB and UBA data sets in the Camisea area as there was still data coming in as this project was winding down 3. Obtain the better processed seismic for some of the data sets. The most notable would be in with the Shell data set in the Camisea area where some of the data supplied to PARSEP had only a special amplitude processing, and the Elf data in the Ene Basin where a better reprocessed data set is known to exist 4. Scan critical seismic lines in the area where there is currently no SEGY data to create a more representative regional data set 5. Incorporate the development wells of the Ucayali into the database with proper bottom hole locations.

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6. Resolve the coordinate problem that seems to exist in the Camisea area as this project found it necessary to utilize two different projections in the Basin to have all the wells tie the plotted seismic data. The second part of the project was completed up to the point of developing a regional stratigraphic and tectonic framework in the Basin that can be used as a building block for future studies. As a result of this study, additional work in the following areas is recommended, 1. Basin modeling at a number of critical point in the Basin be done incorporating the concepts advanced in this study to further understand migration and timing better. 2. A hydrodynamic study is strongly recommended, as fresh water flushing in the Cretaceous is a major exploration risk. Also with such a strong drive, tilted oil water contacts in this Basin may be important and may help better explain the failure of some wells. 3. A further investigation into why some many wells within the Basin foreland structures have excellent hydrocarbon shows but are dry holes or lack sufficient accumulations to be economically viable. Is this a problem of seals, migration/structural timing, or hydrodynamics? This was a problem tackled during the course of this project but one that was not successfully resolved. 4. Complete a detailed seismic sequence stratigraphic study in the Basin to further investigate the possibility of large stratigraphic traps in the Basin. The most attractive area without much doubt in Ucayali Basin is within the fold and thrust belt along its entirety but particularly, in the area of the Oxapampa wells where a considerable gas column has already been discovered in one of the wells, and in the Camisea area. In the foreland, there are still a large number of undrilled structures of which this report documents two that with further understanding of the points addressed above, may be attractive drilling targets. The final point to emphasize is that this Basin has multiple, mature source rocks and there apparently has been large quantities of oil migrating through the system as evidenced by the numerous shows in most of the wells drilled in the Basin. Stratigraphic traps should therefore have an excellent chance of receiving a significant hydrocarbon charge and this Basin with such a variable stratigraphy because of its complex structural history, should contain numerous ones. This report documents two, one in the Pucará and the other in the Cretaceous.

93

9.0 SELECTED REFERENCES Advantage Resources (2001) Field Geologic Work - Block 87. Anadarko Peru Company (1999) Block 84 Final Report, Perupetro Technical Archive ITP21086 Barros, M.C. & Carneiro, E.P. (1991) The Triassic Juruá Orogeny and the Tectono-Sedimentary Evolution of Peruvian Oriente Basin. Exploratory Implications. Braspetro Internal Report. 18 P. 30 fig. Beicip Franlab (1996) Petroleum Exploration Playtypes Of Sub Andean Basins - Volume 1 Y 2(ARPEL). ITP20403, ITP 20404 Chevron (1997) Block 52 Final Report, Perupetro Technical Archive ITP20347 Coastal (1998) Final Report of The Exploratory Campaign, Blocks: 73 (A, B, C And M) And 74. Perupetro Technical Archive ITP21624. Core Laboratories (1996) Hydrocarbon Source Rocks of the Sub-Andean Basins, Peru. Volumes I, II and III. Perupetro Technical Archive ITP20000-20004. CTI – ChemTerra Int. Consultants (2000) Oil Generation in Sub-Andean Basins in Peru. Report for PARSEP, Perupetro S.A. and Canadian Petroleum Institute. Perupetro Technical Archive. Diaz, G. (1999) Guidebook to Stratigraphy and Outcrop Stratal Patterns of Southwest Marañon Basin – Northeast Huallaga Basin, Tarapoto, San Martín. (Internal Report). 9 p. 18 fig. Elf Petroleum Peru (1996a) Block 66 Peru Final Report. Perupetro Technical Archive ITP20766 Elf Petroleum Peru (1996b) Peru Block 66 Geological Synthesis, Sedimentary Geology. Perupetro Technical Archive ITP20011 Elf Petroleum Peru (1996c) Peru Block 66 Geological Synthesis, Structural Geology. Perupetro Technical Archive ITP20010 GeoMark Research (1996) 94

Peru Oil Study, Regional Petroleum Geochemistry of Crude Oils From Peru, Interpretative Volume and Aromatic Biomarker - Analytical Results. Jaillard, E., Soler, P., Carlier, G., Mourier, T. (1990) Geodynamic Evolution of the Northern and Central Andes During Early to Middle Mesozoic Times: a Tethyan Model. Journal of the Geological Society, London. Vol. 147, pp. 1009-1022. Mathalone, J. & Montoya, M. (1995) The Petroleum Geology of the Peruvian Sub Andean Basins. In: A. Tankard, R. Suárez and H.J. Welsink, Petroleum Basins of South America: Memoir 62, p. 423444. Megard, F. (1979) Estudio Geológico de los Andes del Perú Central. Boletín del Instituto Geológico, Minero y Metalúrgico, 8 serie D, 227 p. Murphy (1996) Peru Block 71 Ucayali Basin Phase I Final Report, Perupetro Technical Archive ITP20137 Occidental Petroleum (1996) Geochemical Evaluation of Outcrops and Seeps. - Final Report, Block 72 (Oxy), ADJ. D, E y F. Perupetro Technical Archive ITP20674-20676. Occidental Petroleum (1998) Reporte Final de Evaluación Geológico - Geofísica, Lote 72 (Oxy). Adjuntos A y B. Perupetro Technical Archive ITP20687-20689. Phillips Petroleum Peru Ltd. (1999) Final Exploration Report Second Exploration Term Block 82. Perupetro Technical Archive ITP21922. Repsol YPF (2001) Block 34 First Exploration Period Final Report. Perupetro Technical Archive ITP21875. Rosas, S. & Fontboté, L. (1995) Evolución sedimentológica del Grupo Pucará (Triásico superior – Jurásico inferior) en un Perfil SW – NE en el Centro del Perú. Volumen Jubilar Alberto Benavides, Sociedad Geológica del Perú. Pp. 279-309. Palacios, O. (1980) El Grupo Pucará en la Región Subandina (Perú central). Boletín de la Sociedad Geológica del Perú, 67, p. 153-162. Pangea Energy (1999) Block 71 Ucayali Basin Peru, Revised Phase II Exploration Period Final Report Perupetro Technical Archive ITP21108.

95

PARSEP Study (2002a) Petroleum Potential of the Huallaga Basin and Adjacent Area. Perupetro Technical Archive ITP21257, 21258. PARSEP Study (2002b) Marañon Basin Technical Report. Perupetro Technical Archive ITP21257, 21258. Pindell, J.L & Tabbutt, D. (1995) Mesozoic-Cenozoic Andean Paleogeography and Regional Controls on Hydrocarbon Systems. In: A. Tankard, R. Suárez and H.J. Welsink, Petroleum Basins of South America: Memoir 62, p.101-128. Robertson Research. Petroleos Del Perú (1990) Informe Final. Evaluación Geológica-Geofísica por Hidrocarburos. Selva Peruana. Lotes 8,31 y 35.Volúmenes 1-4 y Apéndices A-D. Perupetro Technical Archive IT03950-03958 y IT03961-03967. Stanley, G.D. (1994) Upper Triassic Corals from Peru. In: Stanley, G.D. (ed.) Paleontology and Stratigraphy of Triassic to Jurassic Rocks in the Peruvian Andes. Palaentographica Abt. A, 233, p. 75-98. Simon Petroleum Spt (1993) Geology - Hydrocarbon Potential and Prospect Analyses, Ucayali Basin – Peru. Perupetro Technical Archive ITP20480-20481 Tankard, Anthony (2001) Tectonic Framework of Basin Evolution in Peru. Report for PARSEP, Perupetro S.A. and Canadian Petroleum Institute, 23 p. Perupetro Technical Archive. Williams, K.E. (1995) Tectonic Subsidence Analysis and Paleozoic Paleogeography and Regional Controls on Hydrocarbon Systems. In: A. Tankard, R. Suárez and H.J. Welsink, Petroleum Basins of South America: Memoir 62, p. 79-100. Wildcat Well Files, Ucayali Basin and Adjacent Areas. From Perupetro Technical Archive.

96

Datum Near top Chonta Base Cretaceous

Copacabana Tarma Ambo

Top Devonian

Basement

Composite Seismic Line Through South Central Ucayali

Figure 5: Composite seismic line through the South-Central portion of the Ucayali Basin showing a) the magnitude of the Devonian-Ordovician(?) rift Basins, b) the onlap relationship of the Carboniferous Ambo onto the Eohercynian Unconformity, and c) the truncation of the Paleozoic sequences beneath the Nevadan Unconformity at the Base of Cretaceous.

Chonta Base Cret Tarma Eohercynian Unconformity

Ambo

Dev. Mkr

Basement

Seismic Line Rep 35_34-111

Figure 6: Seismic Line in the south central Ucayali Basin showing a significant amount of erosion on the pre Ambo sequences (Devonian) beneath the Eohercynian Unconformity (dk. blue reflector).

W CONTAYA AREA

NW

ORELLANA 1X

HUAYA 3X

MAQUIA 1X

EAST O F NORTH SHIRA MTS CASHIBOYA SUR 29X

TAMAYA 1X

PLATANAL 1X (36 2X)

CAMISEA AREA

LA COLPA 1X

SEPA 1X

MIPAYA 5X

SAN MARTIN 1X

1500

ENE ENE ?

3000

MID MUDSTONE

500

LO W N ER IA A IN SH

DATUM N O IP A TS IT ENE E

3000

SE

I

2000

2000

TARMACOPACABANA

-6000

M e t e r s

-6000

2500 2500

4000

CABANILLAS-CONTAYA

1000

3500

2500

2500

3000

BASEMENT

Figure 13. NW/SE stratigraphic cross-section flattened in the Upper Permian unconformity shows the late Permian post Tarma/Copacabana Group stratigraphy. Orellana 1X is in the SE Marañon Basin.

NW

SEPA 1X

MIPAYA 1X

PAGORENI 1X

SEGAKIATO 1XSAN MARTIN 1X

CHONTA

SAN MARTIN 3

2000

ARMIHUARI 4X CASHIRIARI 1X

CASHIRIARI 3

2500

AGUA CALIENTE

-5200

SE -5200

DATUM BAS E K MID MDST

-5300

-5300 2500

500

-5400

2500

LOWER NIA OR LOWER SS

-5400

2500

M.

SHINAI

2500

-5500

-5500

NOIPATSITE D L T S U R H T

-5600 2500

ENE SS

2500

T L E B

TARMA-COPACAB ANA

-5700

Sepa 1X

Panguana 1X

-5600

Mipaya 1X

CAMISEA

X in 1 Mart San 3X M 1X i 1X S n ri re 1X hiria go to Ca s Pa kia ri 1X CA 3X ga Se ihua CA 2X Arm

200 KM Pongo Mainique

-5700

Figure 15: Stratigraphic cross-section flattened on Base Cretaceous shows detailed late Permian stratigraphy. Note excellent log correlation in Shinai, and two 10 m. thick anhydrite beds in the Middle Mudstone Formation and anhydrite beds in the Noi Sandstone Patsite Member.

Figure 22: Structural profile G through the central Ene Basin modeled from the interpretation of seismic line Elf96-09 (after Elf, 1996c). In this region, the principal detachment surface and zone of multiple imbrications, is interpreted to be within the Cabanillas Formation. The Elf interpretation has the western margin of the Shira Mountains as an ‘old’ high controlled by a series of down to the west normal faults of substantial displacement that acted as a buttress to eastern the advancing thrust front.

SOUTH

NORTH

UB14-4 UBA22-39

Cretaceous Ambo Devonian

UBA23-37

Seismic Line UB 14-04

Cretaceous

Devonian

Seismic Line UBA 22-39

Seismic Sections aligned vertically by the crestal closure of the San Martin Anticline

Devonian

Seismic Line UBA 23-37 Figure 27: Series of three seismic lines aligned on the San Martin Anticline showing the northeast propogation of the thrust front into the southern Ucayali Basin from west to east.

Figure 30: Pozo Time Structure, Ucayali North.

Figure 31: Base Cretaceous Time Structure, Ucayali North.

Figure 32: Copacabana Time Structure, Ucayali North.

Figure 33: Contaya Time Structure, Ucayali North

Figure 34: Pozo-Base Cretaceous Isochron (Ucayali North)

Figure 35: Base Cretaceous – Contaya Isochron (Ucayali North)

Appendix 1: Chronological listing of Ucayali Basin New Field Wildcats. Discovery wells are highlighted with bold font Well Name

Operator

Status

Comp Comp Comp Year Mon

Day

Mashansha 1X

Repsol

P&A OS

2002

8

Agua Caliente 31D -1X

Maple

P&A OS

2000

5

9

Panguana 1X

Phillips Petroleum Peru

P&A

1999

2

9

Shahuinto 1X

Pangea (Peru) Energy Ltd.

P&A OS

1998

11

1

Pagoreni 1X

Shell Prospecting & Dev.

P&A GAS

1998

11

1

Chio 1X

Quintana Minerals Peru

P&A

1998

8

8

San Alejandro 1X

Pan Energy E&P Ltd

P&A OGS

1998

5

9

Rashaya Sur 1X

Pluspetrol Peru Corp

P&A OGS

1998

4

Insaya 1X

Coastal Peru Ltd

P&A

1996

5

Cachiyacu 1X

Petroperu SA

P&A OS

1992

4

Platanal 1X

Occidental Peruana Inc

P&A

1989

5

22

La Colpa 1X

Occidental Peruana Inc

P&A OS

1989

3

8

Mipaya 1X

Shell Prospecting & Dev.

GAS

1987

8

7

Armihuari 4X

Shell Prospecting & Dev.

GAS

1987

5

25

Cashiriari 3X

Shell Prospecting & Dev.

GAS

1986

12

9

Aguaytia Sur 4XD

Petroperu SA

P&A GS

1986

1

11

Cashiboya Sur 1X

Petroperu SA

P&A

1985

2

10

Huaya 4X

Petroperu SA

P&A

1984

12

7

Huaya 3X

Petroperu SA

SUSP

1984

6

15

San Martin 1X

Shell Prospecting & Dev.

GAS

1984

3

19

Sepa 1X

Shell Prospecting & Dev.

P&A OGS

1983

9

11

Amaquiria 1X

Petroperu SA

P&A OS

1983

2

7

Rio Caco 1X

Burmah Oil plc

P&A

1976

6

13

Sanuya 1X

Burmah Oil plc

P&A OS

1976

5

7

Tamaya 1X

Burmah Oil plc

P&A

1976

2

22

Tiruntan 1X

Burmah Oil plc

P&A

1976

1

1

Runuya 1X

Hispanoil Sucursal del Peru P&A

1975

11

13

Neshuya 1X

El Oriente

P&A

1972

12

19

Tahuaya 1X

Mobil Corp

P&A

1967

9

3

Pisqui 1X

Mobil Corp

P&A

1967

7

2

Oxapampa 17C 1

Cerro de Pasco Petroleum

P&A

1965

11

18

Oxapampa 19 2

Cerro de Pasco Petroleum

P&A

1965

9

12

Oxapampa 19 1

Cerro de Pasco Petroleum

P&A GS

1965

5

13

Aguaytia 1X

Mobil Corp

GAS

1962

1

12

Oxapampa 07 2

Cerro de Pasco Petroleum

P&A

1961

11

6

Oxapampa 07 1

Cerro de Pasco Petroleum

P&A

1961

9

1

9

1

Zorrillo 1X

Mobil Corp

P&A OS

1961

4

3

Pacaya 1X

El Oriente

OIL

1958

9

9

Maquia 1X

El Oriente

OIL

1957

3

6

Inuya 1X

El Oriente

P&A

1956

11

24

Santa Clara 1A

Peruvian Oil and Mineral

P&A

1956

9

6

Cashiboya 1A

El Oriente

P&A

1956

8

24

Chonta 1X

Texas Petroleum Co

P&A

1955

5

16

Coninca 2X

El Oriente

P&A

1952

3

4

Coninca 1X

El Oriente

P&A

1949

12

31

Santa Clara 1X

Empresa Petrolera Fiscal

P&A

1948

4

8

Rayo 1X

El Oriente

P&A

1947

9

30

Agua Caliente 1A

Ganso Azul

OIL

1939

2

26

Agua Caliente 1X

Ganso Azul

P&A OGS

1939

2

2

2

NW

ORELLANA 1X

SANTA CLARA 1A

INSAYA 1X

HUAYA 3X

16 KM

11 KM

13 KM

MAQUIA 1X 25 KM

CACHIYACU 1X

14 KM

INUYA 1X

PACAYA 1X

14 KM

5 KM

CASHIBOYA 1A

CASHIBOYA SUR 29X

12 KM

SE

29 KM

500

TERTIARY 0

0 500

500

N

500

DATUM

1000

500

CHONTA 1000

1000

1000

500

VIVIA

500

1500

1000

500

1000

AGUA CALIENTE

1000

1000

-1000

RAYA

500

CUSHABATAY

-1000

1000

1500

1500

SARAYAQUILLO

1000

?

1500

TARMA COPACABANA

2000

PUCARA

-2000

M e t e r s

2500

2000

REMOVED 500 M REPEAT COPACABANA-ENE

AMBO-CABANILLAS-CONTAYA -2000

MITU 2500

ENE

BASEMENT GREEN SS

3000

-3000

-3000 Santa Catalina 2X

30 KM

U C S

M

H

O

3500

A

U N

B

Orellana 3X

T

A

A

T

Santa Clara 1X

I

Rayo 1X

Y

N

A

Santa Clara 1A

C

S

O

Huaya 3X

4000

Huaya 4X

T A

-4000

A

Cachiyacu 1X

Y

Maquia 1X

N

Insaya 1X

SECTION 1

-4000

Amaquiria 1X Pacaya 1X

Inuya 1X Cashiboya 1A

Cashiboya Sur 29X

Pisqui 1X Coninca 1X

F O

-5000

Coninca 2X Tiruntan 1X

-5000

APPENDIX 2a

NW

HUAYA 3X

ORELLANA 1X

PLATANAL 1X (36 2X)

TAMAYA 1X

CASHIBOYA SUR 29X

MAQUIA 1X

57 KM

36 KM

27 KM

130 KM

55 KM

TERTIARY

0

2000

500

VIVIA

500 500

500

LA COLPA 1X

42 KM

2000

SHAHUINTO 1X

PANGUANA 1X

23 KM

222 KM

500

0

1000 1000

N

DATUM

CHONTA 2500

2500

1000

1500

1000

1500

AGUA CALIENTE

1000 1000

1000

-1000

RAYA BA T AY CUSHA

3000

ENE ?

3000

1500

-1000

2000

1500

DEVONIAN

1500

TARMA COPACABANA 1500

REMOVED 500 M REPEAT COPACABANA-ENE

PUCARA -2000 M e t e r s

2000

CABANILLAS ?

2500

ANANEA ?

CABANILLAS-CONTAYA

2000 2000

CU M

O

S

U

H

N

A

T

B

A

A

IN

Orellana 3X T

A

Y

S

C

O

Huaya 3X

2500

MITU

2500

-2000

BASEMENT

2500

2000

AMBO 3500

SARAYAQUILLO

SE

500

200 KM N

T

Maquia 1X

GREEN SS

A

Y

A

Cashiboya Sur 29X

3000

SECTION 2 SECTION 2 -3000

-3000 D FOL

Shahuinto 1X La Colpa 1X

S AIN UNT MO

-4000

Platanal 1X

RA SHI

4000

T BEL

ENE

Tamaya 1X

UST THR

3500

-4000 LD FO

Panguana 1X

ST RU TH

CAMISEA

LT BE

-5000

-5000

APPENDIX 2b

AGUA CALIENTE DOME

NW

PISQUI 1X

CONINCA 2X

AGUAYTIA 1X

RASHAYA SUR 1X

5 KM

30 KM

3 KM

31 KM

2000

43 KM

38 KM

1000

3 KM

CHONTA 1X

SE

8 KM

2000

TERTIARY

1500 1000

A MP-2000-31D-1X CAL 31D-1X AGUA_CAL_1 A CAL 1X

NESHUYA 5_1

ZORRILLOS 1X

1500

VIVIA

N

DATUM

2500

CHONT A

1500 2000

2500

1500

2000

0

0

AGUA CALIENTE 3000

500

2000

RAYA

2500 2000

2500

PUMAYACU

500

3000

CUSHABATAY

ENE ? 500

SARAYAQUILLO

Y HA AC AM AR

2500

EVAPORITES M e t e r s

-1000

1000

PUCARA

-1000

TARMA-COPACABANA 1500

Amaquiria 1X Pacaya 1X

Inuya 1X

GREEN SS

Cashiboya 1A

30 KM BASEMENT

Cashiboya Sur 29X

Pisqui 1X

-2000

Coninca 1X

-2000

D FOL

Coninca 2X Tiruntan 1X

SECTION 3 Tahuaya 1X

UST THR

Rashaya Sur 1X

Aguaytia 1X

T BEL

Aguaytia Sur 4XD

CABANILLAS-CONTAYA

Zorrillos 1X

Neshuya 1X

Tamaya 1X San Alejandro 1X Chio 1X

Agua Caliente 1X

Agua Caliente 31D 1X Chonta 1X

Sanuya 1X

-3000

Rio Caco 1X

-3000

APPENDIX 2c

NW

CONINCA 2X

RASHAYA SUR 1X

30 KM

-1000

AGUAYTIA 1X

31 KM

1500

2000

RUNUYA

AGUA_CAL_1

NESHUYA 5_1 43 KM

38 KM

180 KM

70 KM

46 KM

1500

TERTIARY

VI VI 2500

2000

CHONTA

3000 2000

3000

2500

C

2000

MID

2500

SHIN NOI PAT AI SI ENE SS TE

RAYA T AY ABA S U H

500

LOW

2000

MUD STON E

ER

SS

2500

500

PUMAYACU

-1000

1500

DATUM

AGUA CALIENTE

-2000

SE

2000

AN

2500 1500

SAN MARTIN 1X

MIPAYA 5X

SEPA 1X

1X

100 KM

-2000

2500

TARMA-COPACABANA 3000

1000

SARAYAQUILLO 2500

EVAPORITES

GREEN SS 1000

PUCARA

M e t e r s

AMBO 3500

1500

CABANILLAS-CONTAYA BASEMENT

CONTAYA -3000

TARMA-COPACABANA

3000

CU M

O

-3000 S

U

H

N

A

T

B

A

A

IN

T

3500 A

C

Y

S

O

1500

N

T

A

Y

A

2000

AMBO

Coninca 2X Rashaya Sur 1X Aguaytia 1X Neshuya 1X D FOL UST THR

CABANILLAS

DEVONIAN

Agua Caliente 1X

CABANILLAS ? RA SHI S AIN UNT MO

T BEL

-4000

CONTAYA

Runuya 1X

ANANEA ? -4000

SECTION 4

SECTION 4

LD FO

Sepa 1X

ST RU TH LT BE

200 KM

CAMISEA Mipaya 1X

San Martin 1X

APPENDIX 2d

N

O X A P A M P A PISQUI 1X CONINCA 2X

5 KM

AGUAYTIA 1X AGUAYTIA SUR 4XD

RASHAYA SUR 1X

30 KM

1000

12 KM

31 KM

2000

CHIO 2X

40 KM

OXAPAMPA 17C-1 OXAPAMPA 19-1 OXAPAMPA 19-2 OXA 17-C-1 OXA 19-1 OXA 19-2

SAN ALEJANDRO 1X

14 KM

120 KM

20 KM

1000

500

7 KM

S

W E L L S OXAPAMPA 7-1 OXAPAMPA 7-2 OXA 7-1 OXA 7-2

5 KM

20 KM

SAN VICENTE AREA

60 KM

1500

1000

TERTIARY

2000

VIVIA

2000

2500

1500

1500

2000

1500

CHONTA

0

N

1000

DATUM

500

0 0

2500

3000

2000

AGUA CALIENTE

2500

2000

2500

2000

RAYA

PUMAYACU

2500

EVAPORITES -1000

500

500

CUSHABATAY

3000

2500

1500 500

1000

2000

1000

SARAYAQUILLO

1000

1000 -1000

3500

CONDORSINGA

3000

PUCARA

CONDORSINGA

1500

EVAPORITES IN AREA WITH THIN-SKIN TECTONICS

ARAMACHAY

3500

ARAMACHAY

2000

CHAMBARA

-2000

GREEN SS

M e t e r s

Cashiboya Su

2000 -2000

TARMA-COPACABANA CHAMBARA

Pisqui 1X Coninca 1X

Coninca 2X

1500

2500

Tiruntan 1X

2500 Rashaya Sur 1X

Aguaytia 1X

-3000

CABANILLAS-CONTAYA 3000

Zorrillos 1X

Aguaytia Sur 4XD

MITU

Neshuya 1X

San Aleja ndro 1X Chio 1X

D FOL

A

l Ca

A 31

D

1X

-3000

X l1 Ca Chonta 1X

Sanuya Rio Caco 1X

IDEALIZED STRATIGRAPHY BELOW MITU

SECTION 5

Oxapampa 19-1 Oxapampa 7-1

Runuya

-4000

BASEMENT

East Shira

S AIN UNT MO

T BEL Oxapampa 17C-1

RA SHI

UST THR

-4000

Tahuaya 1X

West Shira Oxapampa 19-2

Oxapampa 7-2

-5000

-5000

100 KM San Vicente Area

APPENDIX 2e

SE

CHIO 2X

AGUAYTIA 1X

AGUAYTIA SUR 4XD

SAN ALEJANDRO 1X 14 KM

0

42 KM

12 KM

NW

RASHAYA SUR 1X

SW

31 KM

TAHUAYA 1X

TIRUNTAN 1X

25 KM

CASHIBOYA SUR 29X

39 KM

33 KM

1500

NE 0

3000

TERTIARY 2000

VI VI 1500

AN

IAN VIV

2000

CHONTA

2500

DATUM 500

2000

2000

3500

2500

AGUA CALIENTE

2500

3000

2000

-1000

RAYA 3000

1000

2500

-1000

2500

4000

CUSHABATAY

SARAYAQUILLO

2500

EVAPORITES

3500

CABANILLAS-CONTAYA

PUCARA M e t e r s

CONDORSINGA

3000

-2000

-2000

EVAPORITES (SALT)

CABANILLAS-CONTAYA

ARAMACHAY

BASEMENT TARMA-COPACABANA 3500

100 KM

Pacaya 1X

Inuya 1X Cashiboya 1A

CHAMBARA Cashiboya Sur 29X

Pisqui 1X Coninca 1X

-3000

Tiruntan 1X

SECTION 6

UST THR

CABANILLAS-CONTAYA

Coninca 2X

D FOL

GREEN SS

-3000

Tahuaya 1X

Rashaya Sur 1X

Aguaytia 1X

T BEL

Aguaytia Sur 4XD

Zorrillos 1X

Neshuya 1X

San Alejandro 1X Chio 1X

Agua Caliente 1X

Agua Caliente 31D 1X Chonta 1X

-4000

-4000

APPENDIX 2f

WNW

CHIO 2X

SAN ALEJANDRO 1X 14 KM

0

AC 31D 1X 43 KM

A CAL 1X

CHONTA 1X

8 KM

3 KM

TAMAYA 1X

PLATANAL 1X (36 2X)

57 KM

55 KM

LA COLPA 1X 42 KM

2000

2000

SHAHUINTO 1X 23 KM

ESE

500

0

1000

TERTIARY 2000

VI VI

AN

1500

DATUM CHONTA

1000

2500

2500

1500

2500

AGUA CALIENTE 2000

-1000

500

RAYA 500 500

3000

AY ABAT CUSH ENE (?)

-1000

2000

TARMA-COPACABANA

2500

2000

3500

SARAYAQUILLO 3500

1500

3000

3000

1000

ARAMACHAY

2500

AMBO

GREEN SS BASEMENT

M e t e r s

3000

-2000

-2000

CONTAYA

EVAPORITES (SALT)

AMBO-CABANILLAS 1500

PUCARA 3500

BASEMENT

Aguaytia 1X

Aguaytia Sur 4XD

Zorrillos 1X

Neshuya 1X

TARMA-COPACABANA

D F O L

-3000

Chonta 1X

SEC

T IO

N7

Platanal 1X

Sanuya 1X Shahuinto 1X

Rio Caco 1X

La Colpa 1X

R A S H I

T B E L

CONTAYA -4000

-3000

Agua Caliente 1X

Agua Caliente 31D 1X

U S T T H R

CABANILLAS

Tamaya 1X San Alejandro 1X Chio 1X

Runuya 1X

-4000 East Shira

17C 1

M O

O

100 KM

APPENDIX 2g

SW

OXAPAMPA SAN VICENTE AREA

OXA 7-1

60 KM

5 KM

WELLS OXA 19-1

OXA 7-2

17 KM

DATUM

SHIRA MOUNTAINS

1000

WEST SHIRA

OXA 19-2

7 KM

500

AN VIVI

EAST SHIRA

45 KM

50 KM

RUNUYA

SANUYA 3X

32 KM

42 KM

NE

SHAHUINTO 1X

LA COLPA 1X

PLATANAL 1X (36 2X)

18 KM

40 KM

25 KM

TERTIARY

RIO CACO 1X

1X

23 KM

2000

500

-2000

2000

500

1000

2500

CHONTA

-2000

1500

3000 2500

500

1000 -3000

500

1000

PUCARA

1500

1000

AGU A

CAL IENT E RAYA CU SH ABA TAY 2000 SARAYAQUILLO

1000

2500

1000

3000

1500

3000

ENE (?)

2000

TARMA-COPACABANA

1500 1500

2000

3500

GREEN SS

-3000

2500

1000

3500

CONDORSINGA

1500

2000

AMBO-CABANILLAS-CONTAYA 2000

1500

EVAPORITES IN AREA WITH THIN-SKIN TECTONICS ARAMACHAY

2000 -4000

-4000

2000 M e t e r s

BASEMENT CHAMBARA

2500

2500

3000 -5000

-5000

MITU

Tamaya 1X San Alejandro 1X

Agua Caliente 1X

Chio 1X Agua Caliente 31D 1X

Chonta 1X Platanal

IDEALIZED STRATIGRAPHY BELOW MITU TARMA-COPACABANA

1X

Sanuya 1X Shahuinto

Rio Caco 1X

1X

La Colpa 1X

SHI

-6000

RA

UST

7-1

Oxapampa

S

Oxapampa 19-2

AIN

West Shira

Oxapampa

East Shira

UNT

HR D T

7-2

BEL

-7000

Runuya 1X

MO

FOL

Oxapampa 17C-1

Oxapampa 19-1

-6000

S EC TIO N 8

Mashansha 1X

-7000

T San Vicente Area

100 KM

APPENDIX 2h

SW

C

A

M

I

CASHIRIARI 1X

PONGO MAINIQUE 50 KM

S

E

A SAN MARTIN 1X 95 KM

13 KM

VIVIAN

DATUM

-4000

MID

1000

1000

TERTIARY

2000

500

NE

PANGUANA 1X

CHONTA

ARA S S P UC ER UPP ON E DST SS ER LOW NAI SHI ATSITE

MU

2000

NTE AGUA CALIE

?

I

E A IT TS PA I ENE NO

IN SH

2500

1500

-4000

NOIP

2500

ENE TARMA-COPACABANA

2000

1500

M e t e r s

3000

2500

-5000

-5000

GREEN SS

2000 3500 AMBO

Sepa 1X

DEVONIAN CABANILLAS ?

-6000 ANANEA ?

3000

T BEL ST HRU D T FOL

2500

Panguana 1X

SECTION 9

Mipaya 1X

CAMISEA Pagoreni 1X Segakiato 1X Armihuari 1X CA 2X

X in 1 Mart San SM 3X X 1 ri hiria Cas CA 3X

-6000

BASEMENT 50 KM

Pongo Mainique

APPENDIX 2i

N

S MASHANSHA 1X NW

LA COLPA 1X

SHAHUINTO 1X 23 KM

128 KM

PAGORENI 1X

MIPAYA 1X

SEPA 1X 70 KM

61 KM 1000

31 KM

SEGAKIATO 1XSAN MARTIN 1X SAN MARTIN 3 15 KM

1 KM

7 KM

ARMIHUARI 4X CASHIRIARI 1X 13 KM

5 KM

2000

TERTIARY

VI VI

DATUM

SE

CASHIRIARI 3 9 KM

2000

AN

2000 2000

CHONTA

1000

2000

2000

1500

2000 2500

AGUA CALIENTE 0

MID

1500

500

1500

LOW

MUD STON E

ER SS SH INA NO I IP AT SIT E

2000

2500

0

2500

2500 2500

2500 2500

ENE SS 2000

1000

TARMA-COPACABANA

2000

2500

3000

AMBO M e t e r s

BASEMENT

-1000

-1000 1500

D

Chonta 1X

1

GREEN SS

Platanal 1X

3500 Sanuya 1X Rio Caco 1X

Shahuinto 1X

RA SHI

La Colpa 1X

100 KM 2000

Runuya 1X

AMBO

S AIN UNT MO

East Shira

West Shira

SECTION 10

a 19-2

pa 7-2

Mashansha 1X

DEVONIAN

-2000

-2000 LD FO

Sepa 1X

Panguana 1X

CABANILLAS ?

ST RU TH

CAMISEA Mipaya 1X

LT BE

X in 1 Mart San 3X i 1X SM iari 1X ren 1X shir a to C kia ri 1X CA 3X ga Se ihua CA 2X Arm

ANANEA ?

go Pa

Pongo Mainique

APPENDIX 2j

CU M

O

Santa Catalina 2X

S

U

H

N

A

T

Sa

B

A

A

a

A

1A

Y

Santa Clara 1X Rayo 1X Huaya 4X

N

Huaya 3X

O

S

Orellana 3X

Cl ar a

C

IN

nt

T

Insaya 1X

T

SECTION 1

A

Cachiyacu 1X

Y A

Maquia 1X

Amaquiria 1X

Inuya 1X Cashiboya 1A

Pacaya 1X

Cashiboya Sur 29X Pisqui 1X Coninca 1X

Coninca 2X

Tiruntan 1X

SECTION 3 SECTION 6

Aguaytia 1X

D FOL

Ale jand

SECTION 2

Zorrillos 1X

Aguaytia Sur 4XD San

Neshuya 1X

ro 1 X

A

Chio 1X

A

l Ca

31

D

1X

X l1 Ca S E

Tamaya 1X

C TI

Chonta 1X

ON

7

Platanal 1X

Sanuya 1X Rio Caco 1X

SECTION 5

Shahuinto 1X La Colpa 1X

T BEL

RA SHI

UST THR

Stratigraphic Cross-Section Location Map

Tahuaya 1X

Rashaya Sur 1X

SECTION 8 Runuya 1X

Oxapampa 17C-1 Oxapampa 19-1

S AIN UNT MO

East Shira

West Shira

SECTION 10

Oxapampa 19-2

Oxapampa 7-1

Oxapampa 7-2

LD FO

San Vicente Area

SECTION 4

Sepa 1X

ST RU TH LT BE

INDEX MAP GEOLOGICAL CROSS-SECTIONS

Mashansha 1X

Panguana 1X

SECTION 9 Mipaya 1X

CAMISEA

X in 1 Mart Sa n 3 X M 1X i 1X S i n r re 1X hiria go to Cas Pa kia ri 1X CA 3X ga Se ihua CA 2X m r A

200 KM Pongo Mainique

APPENDIX 2k

AGUA CALIENTE 31D – 1X C U

0

S

M

H

O

A

U

B

N T

A

A

T

I

Y

N

A

C

O

S

N

0 T

A

Y

A

BRAZIL Location of Figure 3

Operator: Spud Date: Comp Date: KB: TD:

Maple April 19, 2000 May 9, 2000 232 m. 990.6 m.

0

CALI inches SP mV GR GAPI

100 80

0.20

250

0.20

0

HT60 OHMM HT24 OHMM

RHOB 2000 2 gm/cc 3 NPHI 2000 0.45 none -0.15

CHONTA

UTM:

Formation Tops: M. Chonta Agua Caliente Raya Cushabatay Aramachay Tarma Copacabana

FO LD ST RU TH LT BE

200 KM

Geographic:

X Coordinate Y Coordinate

S AIN UNT MO RA SHI

T BEL ST HRU D T FOL

Agua Caliente 31D 1X

CAMISEA

Cores: DST:

H/C Shows: 3 277 491 587-588m. Lt br oil stain, good pin point flu 603 607-610m. Lt br oil stain, good pin point flu 729 767 Trace fluor various intervals

AGUA CALIENTE

None None

Table 1: Agua Caliente 31X well data

Figure 1: Location of the Agua Caliente 31X Well and Detailed Map (Figure 3)

RAYA

500

1 2 3 4 5

The Agua Caliente Dome is an elongated NW/SE trending 12 by 7.5 km. surface anticline over which the Agua Caliente oil field was discovered in 1938. It produces 44º API oil from the Cushabatay and Raya (Aguanuya and Paco Sands) Formations. The Chonta Formation outcrops on the surface in the core of the structure and the Vivian and lower Tertiary Formations along the flanks. In subsurface as seen in the discovery well, the Agua Caliente 1X (stratigraphic cross-sections 4 and 7), the Cretaceous section directly overlies the Tarma/Copacabana Group including the basal Green Sandstone unit, which is found at the base. This Group in turn overlies the Contaya Formation, which was deposited over a quartzitic Basement. A sequence of Jurassic and Paleozoic age is interpreted to border the core of the dome preserved in erosional contact under the Cretaceous unconformity. It should be noted that the Green Sandstone unit at the base of the Tarma has not been previously interpreted as being present in this well before.

6 7

CUSHABATAY

8

9

10

11

ARAMACHAY PUCARA PRE K COPACABANA

12

The Agua Caliente 31D-1X was programmed to test hydrocarbon accumulations in the flank of the Agua Caliente Dome, west of the oil field. The objectives were the sands of lower Raya (Aguanuya), Cushabatay, Pucara, Ene and the limestones of the Copacabana Formations. The well TD’d at 991m and drilled the programmed objectives with the exception of the Ene Formation. Light oil shows were encountered in very fine-grained sands in the transitional contact between Cushabatay and Raya Formations and slight fluorescence was detected in the top of the Copacabana Formation underlying the Aramachay Formation. No gas shows were encountered. These shows represent stratigraphic traps in discontinuous sands interfingering with shale. The Copacabana limestones contained the typical fusulinid fossils on the top of the unit. The organic rich black shales of the Aramachay Formation are similar to those found in the San Alejandro 1X well where shales had good TOC. Sands of Cretaceous age show the good reservoir character found elsewhere in the Basin. No tests were performed and the well was abandoned as a dry hole. As the well was drilled well off structure (Figures 3 and 4) it is assumed that this well was drilled to test a stratigraphic trap

13 14

1000

TD

Figure 2: Composite log (Cretaceous to TD) of the Agua Caliente 31X Well

APPENDIX 3a 1 of 3

Base Cretaceous 2WT Structure Map Contour interval 50 ms

z

Agua Caliente 31X

Figure 3: Two-Time Structure map on Base Cretaceous over the Agua Caliente Field showing the location of the Agua Caliente 31X well and composite seismic line (Figure 4) through the well and across the Agua Caliente Structure.

APPENDIX 3a 2 of 3

AGUA CALIENTE DOME

WEST

EAST

Pozo TD Copacabana

Base Cretaceous

Contaya Basement

Figure 4: Composite seismic line through the Agua Caliente 31X well illustrating it to having been drilled on the west flank of the Agua Caliente Structure

APPENDIX 3a 3 of 3

C M

O

U

U

S N

H T

A A

B I

A

N

T

S

A

C

Y

O

N

T

Cachiyacu 1X

A

Y

Operator: Spud Date: Comp Date: KB: TD:

A

BRAZIL

Petroperu SA Jan 22, 1992 March 4, 1992 198 m. 1220 m.

CACHIYACU_1X 0

UTM:

Geographic: -74.82582 -7.33383

X Coordinate Y Coordinate

-100 0

D FOL

Formation Tops: M. Pozo Shale Pozo Sand Yahuarango Vivian Upper Sand Cachiyacu Vivian Lower Sand Chonta Agua Caliente Raya Cushabatay

S AIN UNT MO

T BEL

RA SHI

UST THR

LD FO ST RU TH LT BE

200 KM

Cores: DST:

CAMISEA

GRC GAPI SP mV CALIC in

250 100

0.20

100

0.20

LLS ohmm LLD ohmm

NPHI 2000 0.45none -0.15 RHOB 2000 2 gr/cc 3

H/C Shows:

VIVIAN 308 393 431 447 m. 100% fluo, inmed cut 476 476.6 & 479 m. 100% fluo, inmed cut 560 846 1,073 1,168

CACHIYACU 2 1

LOWER VIVIAN 500

DST 1 & 2 CHONTA

61 SWC 395-1214 m. Between Top Vivian and Cushabatay 1 and 2. Vivian Two DST's 476-478 m. with and without WC, Rec SW samples 85,000 ppm 3. Vivian 477.71 - 511.5 Ten (10) RFT's. Two in Top Vivian found oil grad (0.36 psi/ft) and 8 in Upper Vivian water grad (0.43 psi/ft), all in one single reservoir

Table 1: Cachiyacu 1X well data Figure 1: Location of the Cachiyacu 1X Well

AGUA CALIENTE

The Cachiyacu Structure is an asymmetrical NW/SE trending anticline located on the western border of the Contaya Arch and bounded on the NE flank by the NE and E verging Contamana/Cashiboya Thrusts. It runs for 33 x 6 km with a vertical fault closure of 430m at the base of Cretaceous and a net closure of 56m with 4,566 acres at the top of Cretaceous. The Cachiyacu/Insaya and the neighboring Huaya/Maquia/ Pacaya structural alignments are related tectonically to the Contaya Arch and to the last tectonic pulses of Tertiary age. No seismic data was provided to PARSEP over this well, as part of this study. The Cachiyacu 1X well is located on the crest of the anticline defined by the 1989-1990 Seismic, on seismic line MQ-90-16, SP 345, and 14 km to the east of the Maquia oil field. Original primary objectives were the Cretaceous Vivian, Cachiyacu, Chonta, Agua Caliente and Cushabatay Formations and the Paleozoic Tarma (Green Sandstone) to a PTD of 1497m. However, the well was TD’d at 1220m in the upper Cushabatay, due to rig capacity. Tops for the Raya and Cushabatay Formations were found 24 and 7m higher respectively than in the prognosis. No shows were encountered in the cuttings. The only oil shows were observed in SWC’s at 447m in the Cachiyacu Formation and at 476.6 and 479m in the top Lower Vivian Formation. The interval with shows is interpreted as containing movable oil as determined from wireline logs. The test of the Lower Vivian very likely had communication with the underlying wet massive sandstones, since RFT’s pressures detected the presence of a single reservoir. Although a negative SP indicates flushing, some sandstones produced salt water indicating that they are isolated and protected from flushing. The area has excellent reservoirs with porosity in excess of 20-25%. Permeability ranges from 50-70 to 150-350 were found in the Vivian in the Cashiriari 1X well. The entire Cretaceous interval and the lowermost Tertiary has well-developed shale seals overlying the reservoirs of Raya, Chonta, and Cachiyacu age. Tertiary age.

1000

RAYA

CUSHABATAY TD

Figure 2: Composite log (Cretaceous) of the Cachiyacu 1X Well

APPENDIX 3b

M

C U O

U

S N

H T

A A

B

A

IN

T

S

A

Y

C

O

N

T

A

Y

A

BRAZIL Location of Figure 3

Operator: Spud Date: Comp Date: KB: TD:

X Coordinate Y Coordinate

Quintana Minerals Peru May 21, 1998 August 8, 1998 266 m. 3823 m. UTM: Geographic: 474,750.59 -75.229612 9,024,113.65 -8.828381

CHIO 1X CHIO 2X

0 0 0

SP MV GR GAPI CALI inches

155 140

0.20

100

0.20

T BEL ST HRU D T FOL

Chio 1X

S AIN UNT MO RA SHI LD FO ST RU TH LT BE

200 KM

CAMISEA

Formation Tops: M. Pozo Shale Pozo Sand Yahuarango Vivian Cachiyacu Lower Vivian Chonta Agua Caliente Raya Cushabatay Sarayaquillo Salt Cores: DST:

Figure 1: Location of the Chio 1X Well and Detailed Map (Figure 3)

HMRS OHMM HRDS OHMM

RHOB 2 gm/cc 3 DPHI 2000 45 none-15 DT NPHI 2000 45 none-15 500us/m100

VIVIAN CACHIYACU

H/C Shows:

LOWER VIVIAN CHONTA

2,074 2,074 2,126 2,187 2,565 2,765 2913.9-2915.4 Fluorescence, C1-C3 Gas 2,928 Sli Gas Show 3070-3083 3,083 3,627

2500 AGUA CALIENTE

None None

RAYA

Table 1: Chio 1X well data

1

The objective of the well was to evaluate a structural closure at the Pucará level and a Copacabana carbonate “mound” feature on the NE corner of Block 81 based on the mapping of 1500km of reprocessed seismic. The main risk was that the interpreted mounds were salt or anhydrite, as carbonate buildup (bioherm) had ever been drilled in the Basin. The mound tested had an areal closure of 3967ha and 300m of vertical closure. Little closure was seen within the Cretaceous sediments (Figure 3), but structural/stratigraphic traps were of secondary importance. The Chio 1X well drilled the mound and proved to it to be salt, capped by a 4 meter-thick anhydrite bed underlying Sarayaquillo (Figures 2 and 4). The presence of salt water was detected as the mud chlorides increased from 7000 to 36000 ppm Cl after a significant drilling break 3 m above the top of the evaporites was encountered. Drilling resumed after the setting of a 7" liner, 21m above the top of Salt, but drilling was eventually suspended after intersecting 189m of salt. Preliminary interpretation of the VSP indicated a lithology with faster velocity than salt was present some 100 to 130m deeper. The Salt was interpreted as being 350m in thickness of which 189m had already been drilled. The Cretaceous and Sarayaquillo sections were drilled encountering few and poor indications of hydrocarbons. The base of Raya and the base of Cushabatay had slight C1-C3 shows. Based on drilling results the well was not tested and it was abandoned as a dry hole. No closed structure develops below or above the salt at Chio, although the salt pillows grew in pre-Cretaceous time as a large portion of the Sarayaquillo Formation is eroded above by the overlying pre-Cretaceous unconformity. No later additional growth is detectable in the Chio salt mound. PARSEP’s Base Cretaceous 2WT Structure Map shows a west dipping monocline away from the San Alejandro structural trend (Figure 3). A positive stratigraphic correlation with the San Alejandro 1X well identifies the strong seismic reflector below the salt as Top Pucará at 2.315 msec on seismic line NP-31 presented in Figure 4. These saline anomalies had been mapped previously by Petroleos del Peru throughout a large portion of the Ucayali Basin (Reategui, 1984). The well proved the “mounds” to be salt located stratigraphically between the Sarayaquillo and the Pucará.

CUSHABATAY

3000 SARAYAQUILLO PRE K

3500

SALT

TD

Figure 2: Composite log (Cretaceous to TD) of the Chio 2X Well

APPENDIX 3c 1 of 2

EAST

WEST Base Cretaceous 2WT Structure Map Contour interval 50 ms Pozo Chonta

Chio 1X

Base Cretaceous

Z

Seismic Line NP-31

Salt

TD Salt

Pucará Copacabana Cabanillas

Contaya

Basement

Figure 3: Two-way time structure map on the Base Cretaceous showing monoclinal west dip through the Chio location

Figure 4: Seismic line NP-31 through the Chio 1X well location

APPENDIX 3c 2 of 2

INSAYA 1X M

C U O

U

S N

H T

A A

Location of Figure 3 B I

A

N

T

S

A

C

Y

O

N

Insaya 1X

T

A

Y

A

BRAZIL

D FO L S AIN UNT MO

T BEL

RA SHI

UST THR

FO LD ST RU TH LT BE

200 KM

CAMISEA

Operator: Spud Date: Comp Date: KB: TD:

Coastal Peru Ltd April 13, 1996 May 9, 1996 164 m. 1365 m.

SL CPL-IN-95-01, SP 1395 X Coordinate Y Coordinate

UTM: Geographic: 491,250.00 -75.0824954 9,209,788.00 -7.1544384

Formation Tops: M. Pozo Shale Pozo Sand Yahuarango Vivian Upper Sand Cachiyacu Vivian Lower Sand Chonta Agua Caliente Chonta Repeat Agua Caliente Repeat Cores: DST:

Figure 1: Location of the Insaya 1X Well and Detailed Map (Figure 3)

0 0 0

GR GAPI SP mV CALI inches

200 0.20

150 100

500

0.20

LLS ohmm LLD ohmm

RHOB 2000 2 gr/cc 3 DT NPHI 2000 0.45 %-0.15 500us/m100

VIVIAN

1C

H/C Shows: 402 455 482 534 601 Local Faint Fluor in Cores 682 739 1,027 1,040 1,294

2C

HUCHPAYACU CACHIYACU

3C 4C 5C 6C

LOWER VIVIAN

CHONTA

6 Continuous cores, 2 in Vivian Upper Sand and 4 in Cachiyacu. None

Table 1: Insaya 1X well data

Insaya is a NW/SE trending Andean age anticline parallel to and west of the Contamana Mountains bounded on the NE flank by a thrust fault. Reserves were calculated to be 39 MMBO (46% fill up case), with 35 milliseconds of fault independent relief. Minimum reserves to be economic and potential reserves were calculated as 25 and 209 MMBO, respectively. According to the original interpretation Insaya is located closer to a potential Permian Ene source graben (to the west) than Maquia. Risk involved source rock presence, migration, trap timing and hydrodynamic flushing. The Insaya 1X well was programmed to test the Cachiyacu and Vivian Formations on the crest of the NW highest culmination, 25km to the NW of the Maquia oil field. A coring program was designed to see physical evidence of hydrocarbons for extensive testing operations in an area with expected high resistivity on logs. The well basically proved the pre-well structural interpretation. No gas or oil shows in the mud and cuttings was noted and only local faint fluorescence with no cut was observed in the Cachiyacu. Reservoirs all had good measured porosity and permeability of up to 30% and 1073mD respectively. Most, if not all, sands in Vivian, Chonta and Agua Caliente were found with fresh water (see –SP in front of sands in Figure 2). No tests were performed and the well was abandoned as a dry hole.

1000

THRUST FAULT

AGUA CALIENTE THRUST FAULT CHONTA REPEAT

PARSEP TWT seismic map at Base Cretaceous in Figure 3 shows the Insaya Structure with its two culminations. Figures 2 and 4 of the log and a seismic section shows that the well cut a thrust fault at 1040m near the top of the Agua Caliente Formation and drilling continued into the footwall section of a repeated Chonta and Agua Caliente interval. The Insaya well 1X tested a valid structural closure in Vivian. An explanation for the lack of success may be either one of freshwater flushing, age of structuration (post-dating hydrocarbon migration or lack of adequate hydrocarbon charge to sufficiently charge the structures in the area. From the results of the well indicate that the postulated Ene source kitchen of Coastal, does not appear to be present. The anticipated source rock for this area is believed to be the Pucará as it is in the Maquia field.

AGUA CALIENTE REPEAT

Figure 2: Composite log (Cretaceous) of the Insaya 1X Well

APPENDIX 3d 1 of 3

Base Cretaceous 2WT Structure Map Contour interval 20 ms

z

INSAYA 1X

Seismic Line IN9501

Figure 3: Two-way time structure map on the Base Cretaceous over the Insaya Structure

APPENDIX 3d 2 of 3

SOUTHWEST

NORTHEAST

Seismic Line IN9501

Pozo

TD Agua Caliente (2)

Chonta Agua Caliente Cushabatay Base Cretaceous Top Paleozoic Copacabana

Figure 4: Seismic line IN-95-01 across the Insaya Structure

APPENDIX 3d 3 of 3

M

C U O

U

S N

H T

A A

B I

A

N

T

S

A

Y

C

O

N

T

A

Y

Operator: Spud Date: Comp Date: KB: TD:

A

Repsol June 7, 2002 (2002) 334 m. 2182 m.

MASHANSHA 1X 0

BRAZIL

0

SL 35-REP--99-128, SP UTM: Geographic: 676,642.80 -73.386111 X Coordinate 8,841,947.40 -10.471892 Y Coordinate D FO L S AIN UNT MO

T BEL

RA SHI

UST THR

Location of Figure 3

Mashansha 1X

LD FO ST RU TH LT BE

200 KM

CAMISEA

Figure 1: Location of the Insaya 1X Well and Detailed Map (Figure 3)

Formation Tops: M. Yahuarango Vivian Upper Sand Cachiyacu Vivian Lower Sand Chonta Agua Caliente Tarma Copacabana Green Sandstone Ambo Basement

0 0

CALS IN GR GAPI SP mV SP5 mV

100

0.20

200

0.20

200

0.20

600

0.20

H/C Shows: 1,048 1,094 1,128 1,151 1,349 1,379 2,008 2,038 2,078

IDPH OHMM 2000 SFLU OHMM 2000 AHT20 RHOB OHMM 20000 2 gm/cc 3 AHT30 NPHI DT OHMM 20000 0.45none -0.15 500us/m100

VIVIAN CACHIYACU LOWER VIVIAN CHONTA

Up to 50% lt br oil stain in SWC. v. slow cut fluor Commn fluor in SWC. Oc. Tr. cut fluor tr to 80% pale to bright yellow flu , loc cut fluor, res ring mod to fast strong stream mky wh cut fluor

Rec 67 SWC in 3 Runs from 1355 to 2035 m., Cores: DST: 1. Green Sandstone 2009.2-2010.8 m. Rev out 78.5 bbls Fm Water 71000 ppm Cl 2. Copacabana 1473.4-1479.5 m. Rec 1561 bbls Fm fluid 4000 ppm Cl with H2S max 28 ppm 3. Agua Caliente 1355-1361.2 m. Rev out 1587 bbls Fm fluids and 1.38 % oil

DST 3 AGUA CALIENTE

3

PRE K COPACABANA

DST 2

2

1500

Table 1: Mashansha 1X well data

The Mashansha structure is a N/S trending four-way dip closure located in the NE portion of Block 35. It presents two culminations with the northern one extending into Block 34. The Mashansha 1X well was a proposed basement test to a PTD of 2,500m to test the south culmination of the Mashansha structure which had a mapped vertical relief of 70-60m within the objective Paleozoic and Cretaceous sections. Primary objectives for the well were the Carboniferous Ambo and the Green Sandstone, the basal Tarma Group unit, and a secondary objective was within the sandstones of the lower Chonta Formation. The expected source rocks were to be from shales of the Ambo Group, the source of the gas/condensate in the Camisea area to the southwest, the Devonian Cabanillas and late Permian age Ene Formation. The objectives were found over 100m deeper and the Basement some 370m deeper than in the prognosis. A thin Ambo section overlies Basement and the Cabanillas is absent. PARSEP stratigraphic and seismic interpretations are shown in accompanying Figures 2,3 and 4. Based on regional correlations the Mainique or Ene Formations is absent in the well, and a thin Agua Caliente section is found overlying the Copacabana Formation, which is supported seismically (Figure 4). The PARSEP generated TWT map on the Base Cretaceous (Figure 3) shows that the well was not drilled on the structural culmination in time which is located to the south, and that the well was located just inside the last closing contour. The well, however, was drilled on a depth conversion, which indicated the well was drilled near the structural crest of the feature (Personal Comm. Burlington Resources). Significant hydrocarbon shows within the Paleozoic section of this well indicate that hydrocarbons have been generated in the area and migrated through the section. Just to the east of the well, there is an interpreted north trending Lower Cretaceous channel (Section 5.0 this report) that is in lateral communication with the upper Paleozoic section. This being the case, there may not have been a lateral seal for the section penetrated at the Mashansha location.

DST 1 1

2000

GREEN SS AMBO BASEMENT

Figure 2: Composite log (Cretaceous to TD) of the Mashansha 1X Well

APPENDIX 3e 1 of 3

Base Cretaceous 2WT Structure Map Contour interval 20 ms

Composite Seismic line displayed in Figure 4

Figure 3: Composite seismic line through the Mashansha 1X well and across the highest (in time) mapped portion of the structure.

APPENDIX 3e 2 of 3

E

W

N

REP-35-128

S

REP-35-101

W

E SW

REP-35-132

NE

SHL-UB-59

HIGHEST LOCATION IN TIME ON THE MASHANSHA STRUCTURE

Pozo Chonta

Base Cretaceous Tarma

Ambo Devonian

TD Basement

Basement

Figure 4: Composite seismic line through the Mashansha 1X well

APPENDIX 3e 3 of 3

PAGORENI 1X C U S

M

H

O

A

U N

B

T

A

A

T N

S

O

Y

N

C

I

A

T A Y

Shell Prospecting & Dev. June 30, 1998 November 1, 1998 472 m 3426 m

X Coordinate Y Coordinate

UTM: Geographic: 729,859.00 -72.900456 8,702,552.50 -11.701825

0

A

Operator: Spud Date: Comp Date: KB: TD:

BRAZIL

S AIN UNT MO RA SHI

T BEL ST HRU D T FOL

Location of Figure 3

LD FO

Formation Tops: M. Pozo Shale Pozo Sand Yahuarango Charophites Vivian Cachiyacu Lower Vivian Chonta Agua Caliente Mid Mudstone Lower Nia Shinai

0 0

SP mV GR GAPI CALI inches

150 200

0.20

100

0.20

H/C Shows: 2,336 2,549 2,600 2,620 2,680 3,105 3,210 3,229 3,378

LLS ohmm LLD ohmm

TNPH 2000 0.45V/V -0.15 RHOB DT 2000 2 gm/cc 3 500us/m100 VIVIAN

5

CACHIYACU

Slight Gas Shows Slight Gas Shows Slight Gas Shows Good Gas shows below 3000 m. Good Gas shows Gas shows Good Gas shows Gas shows

LOWER VIVIAN 6

CHONTA

TH ST RU LT BE

200 KM

Pagoreni 1X

CAMISEA

Figure 1: Location of the Pagoreni 1X Well and Detailed Map (Figure 3)

Cores: DST: 1. (1A) Lower Nia 3340-3350 m. 9.9 MMSCFG/D (0.28 MM m3 GD) 28/64" CHK 2.(1B) Lower Nia 3230-3350, Re-run DST 1A + additional sands 3340.3-3350.3, 3332.3-3340.3, 3315-3325, 3287-3297, 3261-3271, 3241-3251, and 3230-3240m. (68M) 18.7 MMCFG/D (0.53 MM m3/D) 40/64" CHK 3. (1C) Agua Caliente and Lower Nia 3137-3350 DST 2 and 3196-3206, 3181-3191, 3152-3162 and 3137-3147. 31.6 MMCFG/D (0.896 MMm3/D) 1" CHK, 107BAR THP

Table 1: Pagoreni 1X well data

3000 7

16

Pagoreni is the latest in a series of hanging wall closures drilled along the northwest trending Camisea fold and thrust belt of the southern Marañon Basin. The structure is located to the NW of the world-class gas/condensate discoveries San Martin and Cashiriari and to the SE of a much smaller gas/condensate discovery, Mipaya, all of which were drilled by Shell in the 1980’s. Hydrocarbons for all these accumulations are most likely derived from coaly shales of the Ambo Group.

GAS SHOWS

8

9

10

AGUA CALIENTE

12

DST - 3

The Pagoreni 1X well was drilled 15 km to the NW of the San Martin 1X well to test the hydrocarbon potential of the Cretaceous and Permian targets in Block 75. The well represented the culmination of a second exploration campaign in the area by Shell. This followed the drilling of the appraisal wells in San Martin and Cashiriari in Block 88-B in an attempt to establish commerciality in the Camisea area. The Pagoreni well was programmed to drill directionally with an inclination of 55º, which represented a horizontal displacement of 2472m to a PTD of near 4000m in the upper Copacabana Group. The primary hydrocarbon targets were the Agua Caliente (Basal Chonta Sand and Upper Nia) and Lower Nia Formations and the secondary targets were the Vivian and Ene Formations and the Lower Chonta sands. The well drilled all and tested successfully most of the primary targets. The main objective Lower Nia found exceptionally well developed 150m of eolian sands (compared to the 35 and 50m drilled in San Martin and Cashiriari, Appendixes 11 and 12). Tests were conducted in the Lower Nia and Agua Caliente Formations, which resulted in the addition of substantial gas and condensate proven reserves to the greater Camisea Area. Reserves DST estimates for the well are 3.2 TCFG, GIP as assessed by Shell.

3

13

14

15

-2

MID MUDSTONE LOWER NIA

17

2

1

18

The well is considered a world-class gas/condensate discovery with potential production rates of over 30 MMCFGD as shown in the accompanying Table 1 and Figure 2. Untested sections includes a similar gas/condensate interval in the bottom 28m of the lower Nia that could DST - 1 not be reached due to mechanical problems, the top 30m interval of the Agua Caliente Formation, and a potential 100m gas column in the lowermost Chonta Formation. The Vivian Formation had poor gas shows while drilling. Additionally, the Pagoreni 1X well did not test the UNDRILLED TOP ENE/NOI hydrocarbon potential of the secondary objectives the, Noi and Ene Sandstone Members reaching a final TD of 3426m in the Upper Shinai Figure 2: Composite log (Cretaceous to TD) of the Pagoreni 1X Well Member. Due to mechanical reasons, the hole was sidetracked twice after leaving two fish in the hole, in the 12 ¼” hole at 2150m in Tertiary red beds and in the 8 ½ ” hole at 2851m in lower Chonta. 19

22

20

21

SHINAI

TD

APPENDIX 3f 1 of 2

SW

NE Seismic Line SH-UBA-22-39 Shown in Appendix 3l Figure 4 Seismic Line SH-UBA-12

Seismic Line SH-UBA-13

Seismic Line SH-UB-12

NW

SE

Figure 3: Dip (above left) and Strike (below left) through the Pagoreni Structure. Note that the Dip line is located to the northwest of the Pagoreni 1X well. Seismic Line SH-UBA22-39 located on the diagram above is shown in Figure 4, Appendix 3l

Seismic Line SH-UB-13

APPENDIX 3f 2 of 2

C M

O

U

U

S N

H T

A A

B

A

T

A

Y

O

S

C

IN

N

Phillips Petroleum Peru December 26, 1998 February 9, 1999 397 m. 2750 m.

X Coordinate Y Coordinate

UTM: Geographic: 790637.739 -72.340231 8780112.022 -11.023678

PANGUANA 1X

T

Operator: Spud Date: Comp Date: KB: TD: A Y A

BRAZIL

RA SHI U MO

T BEL ST HRU D T FOL

Location of Figure 3

INS NTA L FO

Panguana 1X

Formation Tops: M. Pozo Shale Pozo Sand Yahuarango Vivian Cachiyacu Lower Vivian Chonta Agua Caliente Tarma Copacabana Green Sandstone

D ST RU TH L BE T

200 KM

Ambo Devonian

H/C Shows:

DST:

Figure 1: Location of the Panguana 1X Well and Detailed Map (Figure 3)

0 0

1109 1109 1137 1163 1232-1240 C1-C4 1313 1395 1428-1432 C1-C4 1566 m. W eak slow atreaming yel wh cut fluo. 1548 1564-1565 C1-C4. 1638, 1643m. Light brown oil stain, with cut flu. 1578 1635-1645 C1-C3. 1688 m. Brown patchy oil st with flu. 1687 2165-2175 C1-C5.

CAMISEA Cores:

0

32 SW C 1333 (Chonta)-2657 m (Devonian). 2 Rotary. SW C in Tarma and Devonian. See shows above. 1. Green Sandstone. Selective Fm Tester 1688 m. 167.65 SCFG, 2 cubic inches of very light oil gravity. 2. 32 Selective Fm Tester 1332 (Chonta)-2084 m (Devonian) Recovery of Gas and Oil in only the Green Sandstone

CALI inches SP mV GR GAPI

100 150

0.20

200

0.20

HMRS ohmm HDRS ohmm

RHOB 2000 1 g/cm3 3 DT NPHI 2000 0.45 %-0.15 459.20 us/m 131.20 CACHIYACU VIVIAN LOWER VIVIAN CHONTA

1

AGUA CALIENTE

7 8 10 11 12 19 20 13 21 23 2

COPACABANA PRE K

1500 3

4 2 5 3 6 32 33 34 35 27 24 26 31 30 28 29 14 16 15

5

GREEN SS AMBO

4

Pred slst dk gy, gr gy DEVONIAN

36 38 37

Table 1: Panguana 1X well data

The operator’s interpretation is that the Panguana Anticline is a WNW/ESE trending anticline extending 13 km in length and 4 km wide on the SE corner of Block 82. It is described as having three-way dip closure and one-way normal fault closure with the anticline being bounded to the NE by a NW/SE trending normal fault whose throw across the fault is sufficient to seal an 80m HC column by juxtaposed shales. The mapping done by PARSEP (Figure 3) does show that the Panguana well was drilled on a closed structure but one of limited areal extent and one bounded by faults of reverse throw (Figure 4). The well location is located updip from the Camisea fields, an area partially occupied by the Tertiary foredeep basin where thermal modeling suggests the presence of mature source rocks of various Paleozoic ages and kitchen areas. Available seismic does not define major faulting to prevent hydrocarbons migration from these kitchens, where Basin Modeling indicates current generation and migration. The shows encountered during the evaluation of this well would support this concept. The Panguana 1X well was programmed to a TD of 2500m or to top of Basement, to test the Cretaceous Vivian and Oriente Group (including Agua Caliente and Cushabatay Formations) as primary objectives and the Tarma Group as a secondary objective. Potential reservoirs in the Tarma/Copacabana Group were, the basal Green Sandstone, and porous dolomitic zones and possible additional sand and karsted intervals within the Copacabana sequence. The well found the primary objectives Chonta and Agua Caliente and 30m of Lower Vivian sands with fair to good development. The Vivian and Agua Caliente Formations were found 190 and 85m deeper, and the Copacabana and base of Tarma, 105 and 120m shallower than prognosis. The well was TD’d at 2750m in Devonian, possibly Cabanillas Formation. No Cushabatay or Raya Formations were present in the well. PARSEP interprets the Cushabatay and Raya wedges to onlap to the W/NW of the Panguana location and the upper Agua Caliente sands are found resting directly over Copacabana. The thin section assigned by the operator to Ene/Mainique is considered as part of the Agua Caliente Formation. The Copacabana section is thin in this well as a result of erosional thinning beneath the Base Cretaceous unconformity. The pre-Ambo section is generally a thick sequence of coarse clastics that has tentatively been interpreted to be of Devonian age that are often referred to as Ananea in the southern Ucayali Basin. It may also include older sediments as well. Minor oil and gas shows were encountered in the Cretaceous and Paleozoic objectives. Slight amounts of gas and very light API oil were recovered only from the Green Sandstone in a series of open hole Selective Formation Tests taken in the Cretaceous and Paleozoic section. Porosities often exceeded 25% and permeabilities were found in the range of 1300-3500 mD in SWC’s through the Agua Caliente section. The Green Sandstone and Ambo from SWC analysis were found to have porosities as high as 17% with permeabilities in the range of 3-140 mD in the Green Sandstone and Ambo. Evaluation of well results concluded lack of commercial hydrocarbons in Panguana.

2000 42 40

SELECTIVE FM TESTER

6

2500

TD

Figure 2: Composite log (Cretaceous to TD) of the Panguana 1X Well

APPENDIX 3g 1 of 3

Panguana 1X z

Seismic Line TOT 39-220 (Figure 4)

Base Cretaceous 2WT Structure Map Contour interval 10 ms

APPENDIX 3g 2 of 3

WEST

EAST

Seismic Line TOT 39-220

Chonta Base Cretaceous

Ambo Devonian Ananea

Basement

Figure 4: Seismic line TOT 35-220 through the Panguana 1X well location (with synthetic). Note the anomalously thick section of Ananea(?) section beneath the Ambo.

APPENDIX 3g 3 of 3

U C S

M

H

O

A

U

B

N T

A

A

T N

S

O

Y

N

C

I

A

T A Y

Location of Figure 3

A

BRAZIL Rashaya Sur 1X

D FOL INS NTA MOU

T BEL

RA SH I

UST THR

LD FO ST RU TH LT BE

200 KM

CAMISEA

Figure 1: Location of the Rashaya Sur 1X Well and Detailed Map (Figure 3)

Operator: Spud Date: Comp Date: KB: TD:

Pluspetrol Peru Corp February, 1998 April, 1998 467 m. 3497 m.

SL NP 24, 49 m.NW of SP 384 X Coordinate Y Coordinate

UTM: Geographic: 457,196.00 -75.388564 9,099,123.00 -8.149781

Formation Tops: M. Pozo Shale Pozo Sand Yahuarango Vivian Upper Sand Cachiyacu Vivian Lower Sand Chonta Agua Caliente Raya Cushabatay Pumayacu Cabanillas

RASHAYA SUR 1X 0 0 0

SP mV GR GAPI CALI PUL

200 250

0.20

100

0.20

HLLS OHM-M 2000 HLLD RHOB DT OHM-M 2000 2 gm/cc 3 500us/m100

CACHIYACU VIVIAN

H/C Shows:

LOWER VIVIAN

2,353 2,353 2,410 2,481 2,839 3,041 Gas shows C1-C5. Tr to 5% fluorescense 3163-3184m. 3,199 Sli Gas Shows C1-C5. Tr fluorescense 3,374 Gas shows C1-C5. Tr to 15% fluorescense 3280-3289m. 3,417

2500

None Cores: DST: 1. Pumayacu (Lowermost Cretaceous) 3411-3415 m. Rec 8 bbls completion fluid, 79.5 bbls Fm water (42,185ppm Cl) and 58 bbls diesel. 2. Lower Raya 3176-3183 m. Reversed out Rec 2 bbls completion fluid, 80 bbls Fm water (41,192ppm Cl) and 61 bbls diesel and oil. 3. Upper Raya 3049.5-3052 m. Reversed out 0.6 bbls completion fluid, 16 bbls Fm water (42,600ppm Cl)and 39 bbls diesel and oil 40.6 API.

CHONTA

AGUA CALIENTE

Table 1: Rashaya Sur 1X well data 3000 RAYA

3

DST 3

4

Rashaya Sur is one of four independent culminations along the N/S trending Pisqui/Santa Ana structural alignment that extends 75 km. in the NE corner of ex-Block 79. Rashaya Sur is an elongated 7 by 3 km. anticline with a steep eastern flank bordered by a late Andean-aged, high angle thrust fault. This fault appears to be one of several that form a series of en echelon structures (Figure 3) along the overall structural trend. To the west of the well (Figure 5) a spectacular normal fault with over 1.0 msec of throw can be seen. The general orientation of this older fault system is in SW to NE and in general have not experienced much reactivation during the latest Andean orogeny. Typically in the area of Rashaya Sur they act as transfer faults between en echelon fault sets.

DST 2 2

3

CUSHABATAY

2

The well objective was to evaluate the Cushabatay Formation and to drill 173m into an interpreted possible Pucará section to a PTD of 3,500m. The secondary objective were the sandstones of the Raya Formation. Rashaya Sur 1X found all programmed objectives some 80m deeper than prognoisis and the well was TD’d in Paleozoic, identified as Cabanillas by PanEnergy (1999B). Slight oil shows and continuous gas shows (C1-C5) were detected in the Raya, Cushabatay and Pumayacu Formations in unflushed reservoirs which encouraged well completion. The three DST’s did not flow fluids to surface, but the recovery by reversing out was salt water of 42,00 ppm Cl and with only a little oil which was seen in the last test. Probably the extensive gas shows represent residual gas in unflushed Raya, Cushabatay and Pumayacu. The section above Raya is flushed as seen in the –SP (Figure 2).

DST 1 PUMAYACU 1

1

PRE K CABANILLAS TD

Figure 2: Composite log (Cretaceous to TD) of the Rashaya Sur 1X Well

PARSEP interprets the Rashaya Sur structure to be separated from the much larger Rashaya Norte structure by en-echelon Andean age thrust faults as depicted in Figure 3 and 4.

APPENDIX 3h 1 of 3

EAST

Base Cretaceous 2WT Structure Map Contour interval 50 ms

NORTH

Base Cretaceous 2WT Structure Map Contour interval 50 ms

Rashaya Norte Structure

Composite Seismic Line (Figure4) Rashaya Norte Structure

Pozo Chonta Agua Caliente

TD Cabanillas

Base Cretaceous z

Copacabana

Rashaya Sur 1X Seismic Line NP-24 (Figure 5)

Figure 3: Two-Time Structure map on Base Cretaceous over the Rashaya Sur Structure. To the north of the well is the much larger Rashaya Norte Structure.

Cabanillas Contaya

Figure 4: Composite seismic line through the Rashaya Sur 1X location and the Rashaya Norte Structure

APPENDIX 3h 2 of 3

WEST

EAST

Pozo

Chonta TD Cabanillas

Upper Sarayaquillo Lower Sarayaquillo

Salt

Agua Caliente

Base Cretaceous Top Paleozoic

Cabanillas Pucará

Contaya

Copacabana

Figure 5: Seismic line NP-24 through the Rashaya Sur 1X location. Note the 1.0 second displacement on the western-most bounding normal fault to the Structure.

APPENDIX 3h 3 of 3

C M

O

U

U

S N

H T

A A

B I

A

N

T

S

A

Y

C

O

N

T

A

Y

A

BRAZIL Location of Figure 3

D FOL

San Alejandro 1X

S AIN UNT MO

T BEL

RA SHI

UST THR

FO LD ST RU TH LT BE

200 KM

Pan Energy E & P Ltd January 26, 1998 May 9, 1998 271 m. 3572.3 m. UTM: Geographic: 488,567.32 -75.10399 X Coordinate Y Coordinate 9,025,754.69 -8.81332 Formation Tops: M. H/C Shows: Vivian Upper Sand 1,315 Cachiyacu 1,315 Vivian Lower Sand 1,364 Chonta 1,438 Slight Gas Shows Agua Caliente 1,798 Raya 1,984 C1-C5 Best Gas Shows 2128-2175. 2127.5-2145.8 Oil Fluorescence Cushabatay 2,174 Slight Gas Shows Sarayaquillo 2,304 Slight Gas Shows Top 150m. C1-C5 Best GS Bottom 135m Condorsinga 2,862 Gas Shows C1-C5 Aramachay 3,150 Gas Shows C1-C5 Copacabana 3,203 Gas Shows C1-C5 down to TD Copacabana Fusulinids 3213-3216, 3277-3286, 3426-3429 and 3441-3444. 2 Runs, Recovered 53 SWC 2701-3317 m. Sarayaquillo, Cores: Condorsinga, Aramachay and Copacabana DST: 1. Condorsinga 2865.1 - 2886.5 m. Flow 1bbl/hr Diesel Cushion. 1A. Repeat DST 1 with Acidiz. Flow 1bbl/hr Diesel Cu.Est rec 10 bbls Fm water 2. Raya 2128.4 - 2144 Diesel cushion No flow TS. Est recovery 10 bbls Fm fluid, mud, filtrate, water, tr oil. 2A. Repeat DST 2 No Cushion Recover 3603' mainly mud, with assoc gas. Slugging gas, oil and mud. 3. 6 RFT's in Upp Condorsinga 2864-2884 m. add. RFT's in Raya/Cushabatay 2135-2286m. Operator: Spud Date: Comp Date: KB: TD:

CAMISEA

Figure 1: Location of the San Alejandro 1X Well and Detailed Map (Figure 3)

SAN ALEJANDRO 1X 0.20 0 0 0

SP mV GR GAPI CALI IN

200

0.20

200

0.20

100

0.20

IDPH ohmm SFLU ohmm AHT90 ohm. AHT60 ohm.

2000 2000 RHOB gm/cc 3 TNPH DT 2000 0.45 ft3/ -0.15 500 us/m 100 2000 2

CACHIYACU VIVIAN LOWER VIVIAN CHONTA

1500

7

AGUA CALIENTE

RAYA

2000

DST 2 8

2

1

CUSHABATAY

9

PRE K SARAYAQUILLO

11

Table 1: San Alejandro 1X well data

12

13

2500

The San Alejandro structure is one of three culminations on the San Alejandro NNW/SSE trending structural alignment that is bordered by a thrust fault along its eastern flank (Figure 3 and 4). The San Alejandro alignment plunges to the NW and outcrops to the SE in the NW Shira Mountains where an oil seep is present. The shallow Cretaceous objectives are not coincidental with the deeper Paleozoic objectives over the Structure. The well was drilled with the Cretaceous section being targeted as the principal objective. Major risks involved, timing of structuration and meteoric flushing.

DST 1 1

CONDORSINGA PUCARA

2

14

San Alejandro 1X well was programmed originally to test Cretaceous (main), Pucará and Ene reservoirs near the crest of the San Alejandro central culmination, to a PTD of 2978m. The well encountered continuous gas shows (C1-C5) from 2700m to TD in unflushed intervals in the lower Sarayaquillo, Pucará (Condorsinga and Aramachay) and Copacabana (Figure 2). Similar gas shows with oil fluorescence were present in lower Raya in a section protected from flushing (DST 2). Slight gas shows were recorded from Chonta, Raya, Cushabatay and upper Sarayaquillo down to 2350m, in a section with pronounced fresh water flushing. Testing proved a porous tight upper Condorsinga Formation and a non-commercial oil accumulation in the lower Raya, and the RFT’s indicated fresh and salt-water gradients in the upper and lower Cushabatay, respectively. During abandonment procedures, the casing collapsed and the well was abandoned without the possibility of a future re-entry. Post-well studies provided positive identification of the Aramachay (Geochemical biomarkers) and Copacabana (fusulinids in thin sections) Formations, and a correlation between the oil recovered from the lower Raya oil back to a Pucará source rock.

3000 3

15

ARAMACHAY 4

16

18

19

3500 6

The San Alejandro 1X well drilled a Cretaceous culmination near its crest and the flank of a deeper Paleozoic culmination (Figure 3 and 4). The main reservoir objectives were water-bearing and/or flushed by meteoric waters. Residual gas or gas being generated presently was encountered in the structure. The test in Raya proved the presence of oil generation, migration and entrapment in stratigraphic traps that were protected from both regional flushing and deep burial that would have cracked the oil into gas.

COPACABANA

5

17

TD

Figure 2: Composite log (Cretaceous to TD) of the San Alexjandro 1X Well

APPENDIX 3i 1 of 3

Base Cretaceous 2WT Structure Map Contour interval 50 ms

Seismic Line G35-603 (Figure4)

Z

San Alejandro1X

Figure 3: Two-way time structure map on the Base Cretaceous across the San Alejandro location

APPENDIX 3i 2 of 3

WEST

EAST

Seismic Line G35-603

Pozo

Chonta

Base Cretaceous TD Copacabana

Pucará Copacabana

Basement

Figure 4: Seismic line G35-603 through the San Alejandro 1X well location

APPENDIX 3i 3 of 3

SHAHUINTO 1X C M

O

U

U

S N

H T

A A

B I

A

N

T

S

A

Y

C

O

N

T

A

Y

A

BRAZIL Location of Figure 3 D FOL S AIN UNT MO

T BEL

RA SHI

UST THR

Shahuinto 1X

FO LD ST RU TH LT BE

200 KM

CAMISEA

Figure 1: Location of the Shahuinto 1X Well and Detailed Map (Figure 3)

Operator: Spud Date: Comp Date: KB: TD:

Pangea (Peru) Energy Ltd. November, 1998 December, 1998 294 2171

Intersect SL 87-43.5 and 97-03 X Coordinate Y Coordinate

UTM: Geographic: 689,626.27 -73.27385 8,977,646.35 -9.2446

0 0 0

Formation Tops: M. Pozo Shale Pozo Sand Yahuarango Vivian Upper Sand Cachiyacu Vivian Lower Sand Chonta Agua Caliente Ene Sandstone Tarma Copacabana Green Sandstone Ambo Basement

Cores: DST:

SP mV GR GAPI HCAL in

200 200

0.20

100

0.20

AHT30 ohmm AHT90 ohmm

RHOB 2000 2 gm/cc 3 DT TNPH 2000 0.45ft3/ -0.15 500us/m100

VIVIAN CACHIYACU LOWER VIVIAN

H/C Shows:

CHONTA 1000

850 855 861 909 1,125 Occasionaly very weak wh yel cut 1,289 1,303 Poor Oil Shows in Ls & Dol. Tar, dark brown oil stain and loc vis oil in pits 1,865 Poor oil shows in sandstones 1,900 Poor oil shows in sandstones 2,120 Above shows with slight C1-C3 gas

AGUA CALIENTE

PRE K ENE COPACABANA

3 Runs Rec 47 SWC's 1128-2155 m. poor oil shows None

Table 1: Shahuinto 1X well data

1500 1 2

3

PARSEP was unable to re-interpret the Shahuinto area due to the lack of available SEGY digital seismic (Figure 5). As interpreted by the operator Murphy/Pangea Shahuinto is a well defined seismic prospect in ex-block 71 located 240 km N of the giant Camisea gas condensate fields and 180 km SE of Agua Caliente oil field. The structure is an elongated N/S trending asymmetric anticline bounded on the steep eastern flank by an early Andean age high angle thrust fault (Figures 3 and 4). The size of the structure is 42 by 4 km (36,100 acres) with fault closure at the base Cretaceous the vertical closure is 230m). The well itself was drilled within a much smaller four-way dip closure in the northern half of the much larger fault closure as shown in Figure 3. The primary objectives for the well were the Cretaceous Oriente Formations (basically Agua Caliente) and Paleozoic Tarma/Copacabana with secondary targets in the Vivian, Chonta and Ambo Formations, to a PTD of 2,400 m in Basement.

4 5

6

7

8

GREEN SS 9 10

11

AMBO Carb sh & lignite

12

From the seismic line presented in Figure 4, the Shahuinto structure appears to be the result of a graben that was inverted during the late Andean orogeny as the pre-Cretaceous to Basement section on the hanging wall side is considerably thicker than the footwall side. Despite this, all the Sarayaquillo, Ene and the upper Copacabana were truncated by the Base Cretaceous unconformity. The well drilled the expected formation tops of the Vivian, Copacabana and Basement levels at 24, 55 and 226 m respectively shallower than in the prognosis. A thin siliciclastic unit overlying Copacabana was interpreted to represent the basal Ene Formation although it is most likely an interbed within the Copacabana Group as the Copacabana has been erosionally thinned. Poor oil and gas shows were found only in the Paleozoic. The Cretaceous section in its entirety was found wet. The well was plugged and abandoned without testing. The young age of the structure, which probably postdated migration, is believed to be one of the principal reasons for the lack of success of this well.

2000

Common carb sh

BASEMENT TD

Figure 2: Composite log (Cretaceous to TD) of the Shahuinto 1X Well

APPENDIX 3j 1 of 2

Chonta 2WT Structure Map Contour interval 50 ms

TD Basement

PARSEP Seismic Coverage AVAILABLE SEGY DATA

Pangea Seismic Coverage

Shahuinto 1X La Colpa 1X

Figure 3: Two-Time Structure map on the Chonta over the Shahuinto Structure (after Pangea 1999)

Figure 4: (modified from Pangea, 1999) Seismic line 87-43.5 through the Shahuinto 1X well location.

Figure 5: Location of seismic data in the area of ex-Block 71 of Pangea Energy (modified from Pangea, 1999. The lack of available SEGY seismic data (dashed yellow) in this area necessitated the utilization of the Pangea interpretation in the evaluation of the Shahuinto well.

APPENDIX 3j 2 of 2

C U S

M

H

O

A

U N

B

T

A

A

T

I

Y

N

A

C

O

S

N

T

A

Y

Shell Prospecting & Dev. August 7, 1986 December 9, 1986 681 m. 2684 m.

X Coordinate Y Coordinate

UTM: Geographic: 747,158.92 -72.73117 8,686,679.48 -11.87122

CASHIRIARI 1X

A

BRAZIL

D FOL S AIN UNT MO

T BEL

RA SHI

UST THR

FO LD ST RU TH LT BE

200 KM

Operator: Spud Date: Comp Date: KB: TD:

Cashiriari 1X

CAMISEA

Figure 1: Location of the Cashiriari 1X Well

Formation Tops: M. Pozo Shale Pozo Sand Yahuarango Charophytes Vivian Upper Sand Cachiyacu Vivian Lower Sand Chonta Agua Caliente Lower Nia Shinai Noipatsite Ene Sandstone Tarma Copacabana

H/C Shows:

NS, NGS K Ø Sw *

ABREVIATIONS Net Sand, Net Gas Sand Permeability Average Porosity Water Saturation Lower Chonta only

0 0 0

CALI inches SP mV GR GAPI

100 150

0.20

200

0.20

SFLU OHMM LLD ohmm

RHOB 2000 2 gm/cc 3 NPHI DT 2000 0.45none -0.15 500us/m100

2000

1936 2020 2047 2060 2098 2349 2419 2469 2541 2627 2674

Good Gas Shows C1-C4: 2285-2343 Good Gas Shows C1-C4 Good Gas Shows C1-C4 Slight Gas Shows Good Gas Shows C1-C4 Good Gas Shows C1-C4 Slight Gas Shows

NS m. 20 16 20 55* 87

K, mD

1004

Ø % Sw % 16 24 16 73 17 89 15 58*

148

13

60-70

20

9 7 Totals

44-37 60

VIVIAN CACHIYACU LOWER VIVIAN 3

CHONTA

DST 3 53 27 243

None Cores: DST: 1. Noipatsite Member 2577-2581 and 2593-2599 Production: 22.2 MMCFGD x 601 BCD x 0 WPD x 1" CHK 2. Agua Caliente (Upp Nia) 2378-2385 and 2366-2374 Production: 26.5 MMCFGD x 711 BCD x 1" CHK 3. Lower Vivian 2087-2096 and 2070-2079 Production: 22.7 MMC31 MMCFGD x 587 BCD x 48/64" CHK

Table 1: Cashiriari 1X well data

Cashiriari is an E/W asymmetric hanging wall structure of Andean origin extending 30 by 5 km essentially parallel and to the south of the San Martin Anticline, a world-class gas/condensate discovery completed by Shell in 1984 in the south Ucayali Basin. Hydrocarbons are likely derived from coaly shales of the Paleozoic Ambo Group.

1

3

AGUA CALIENTE 2

2

DST 2

The Cashiriari 1X well was located near the crest of the structure to test the productive hydrocarbon section found by the San Martin 1X and Segakiato 1X, the discovery and appraisal well respectively of the San Martin accumulation. The primary objectives for the Cashiriari well were the Agua Caliente and Lower Nia Kaatsirinkari Formations and the secondary objectives, the Vivian, Ene and Copacabana Formations, and to test a potential oil rim of the objectives. The well found Agua Caliente some 250m deeper than prognosis and a Permian section that had stratigraphic variations relative to the San Martin 1X well. The well was sidetracked from 2285m after the DP got stuck at 2505m in the Shinai and subsequently drilling continued to TD in the upper Copacabana.

LOWER NIA PRE K 4

SHINAI

6

An extensive hydrocarbon column was tested partially by 3-cased whole Production Tests, in the Noi Sandstone Member, in the top of Agua Caliente Formation and in the Vivian Lower Sand. These tests, shown in the accompanying Table and Figure, also proved a world-class gas/condensate discovery with potential production in excess of 60 MMCFGD and 27-32 bbl/MMSCF. Untested Potential Productive sands included intervals in lower Ene Sandstone, Noi, all Lower Nia, lowermost and uppermost Agua Caliente, lowermost Chonta and all Upper Vivian. The Paleozoic pre-Ene sequence was not drilled.

2500

NOI PATSITE

5

7

ENE SS 9

Reserve calculation for the field amounted to GIIP 9.7 TCFG (revised in 1998 with early results of Shell appraisal drilling) and liquids IIP 434 MMSTB with recoverable reserves of 260 MMSTB. DeGolyer and MacNaughton (1998) confirmed 5.44 and 3.45 TCFG of Proved and Probable/Possible gas reserves.

1

10

ENE SS

14

A detailed post-well petrophysical evaluation of the Cretaceous and Permian interval was performed using good quality logs by Shell, 1987. All intervals were found to be gas bearing (compare Neutron and Density logs in accompanying figure) totaling 258m of net gas sands with porosities between 8 and 20% and hydrocarbon saturations up to 94%. Average values are presented in the accompanying Table 1. The Vivian and Agua Caliente/Lower Nia constitute the main reservoirs, and the Noi and Ene Sandstone Members the secondary reservoirs. RFT pressure evaluation defines two reservoir systems; in the Vivian (GDT 1698m TVDss with mean and potential gas columns of 450 and 600m, respectively), and; in the Lower Chonta/Agua Caliente/Lower Nia/Noi Sandstone/Ene Sandstone (FWL at 2060 m TVDss with a gas column of 200+ m), with gradients of 0.078 and 0.087 psi/ft for the upper and lower systems respectively. The gas composition for the Vivian and Lower Cretacesous/Permian systems would indicate a common origin for both hydrocarbon columns. Lower Tertiary and Chonta shales provide excellent seals, to the reservoirs whereas the thick Shinai mudstone reveal the extend of reservoir fracturing and/or faulting. The Appraisal well, Armihuari 1X was drilled and found the same gas bearing objectives as the Cashiriari 1X well some 300m deeper.

DST 1

8

13

11

15

12

COPACABANA

16

TD

Figure 2: Composite log (Cretaceous to TD) of the Cashiriari 1X Well

APPENDIX 3k 1 of 1

SAN MARTIN 1X

SAN MARTIN 1X

U

S N

H T

A A

0 B I

A

N

T

S

A

Y

0

N T A Y

0

A

SP mV CALI inches GR GAPI

150 100

0.20

200

0.20

LLS ohmm LLD ohmm

RHOB 2000 2 gm/cc 3 NPHI DT 2000 0.45none-0.15 500 us/m 100

BRAZIL

CHONTA

K, mD Ø % Sw % 21 100 20 100 21 100 20* 20*

AGUA CALIENTE

17

LOWER NIA PRE K

3

NOI PATSITE ENE SS

LD ST RU TH

23-46

LT BE

15 9

15

16

SHINAI

200 KM

89 34

2

14

10

FO

15-20

2000

S AIN UNT MO

94

LOWER VIVIAN

1

RA SHI

NS m. 33 25 20 43*

VIVIAN CACHIYACU

ABREVIATIONS NS, NGS Net Sand, Net Gas Sand Permeability K Average Porosity Ø Water Saturation Sw Lower Chonta only *

T BEL

Table 1: San Martin 1X well data

O

UST THR

H/C Shows: Formation Tops: Pozo Shale Pozo Sand Yahuarango Vivian Upper Sand 1722 Slight Gas Shows Cachiyacu 1758 Slight Gas Shows Vivian Lower Sand 1770 Slight Gas Shows Chonta 1805 Good Gas shows 2036-2046 Agua Caliente 2046 Good Gas shows Lower Nia 2117 Good Gas shows Shinai 2151 Slight Gas Shows 2165-2200 Noipatsite 2222 Good Gas shows Ene Sandstone 2315 Good Gas shows Tarma Copacabana 2356 Good Gas shows various zones Green Sandstone 3321 Good Gas shows Ambo 3346 Good Gas shows 3506-3608 Chonta Repeat 3668 Slight Gas Shows Agua Caliente Repeat 3685 Slight Gas Shows Lower Nia Repeat 3752 Slight Gas Shows Shinai Repeat 3780 Slight Gas Shows Noipatsite Repeat 3864 Slight Gas Shows Cores: DST: 1. Copacabana 2509-2513 No flow TS. Rev out 20 bbls influx, no hydrocarbons. 2. Copacabana 2446-2437, 2434-2431 and 2423-2419 m. No flow TS. Rev out 20.2 bbls influx with sl trace of gas. 3. Copacabana Re-run DST 2. No WC. Rev out 50 Bbl influx with no HC. 4. Top Copacabana 2360-2363 m. No fm fluid entry. 5. Top Copacabana 2357-2363 m. DC to surface. Poor fluid entry 0.1 bbl. 6. Ene and Copacabana 2343-2346 and 2357-2363 No fm fluids recovered. 7. Rerun DST 5 with less drawdown. 600 scfg flowed TS with no Fm liquids. 8. Basal Ene Sandstone 2343-2346 m. 3800 SCFG flowed TS. Calculated 10 bbl fm fluid with no oil during backflow due to valve leak. 9. Noi Sandstone 2275-2281 m. 18 MMSCFGDx658 BCPDx658 PSIA FTHP 10. Agua Caliente 2067-2073 m.(Upp. Nia) 23 MMSCFGDx720 BPDCx 0 11. Interval Vivian to Ambo 1721-3668 m. 86 Repeat Formation Tests 12. Repeat K-Permian Section 3668m. - TD. 18 RFT

M

U

O

X Coordinate Y Coordinate

UTM: Geographic: -72.77458 -11.76358

C

C

Shell Prospecting & Dev. October 11, 1983 March 19, 1984 445 3894

D FOL

Operator: Spud Date: Comp Date: KB: TD:

25-70 100

9

San M artin 1X 18 22

CAMISEA

6 8 7 5 4 3 2

1

Figure 1: Location of the San Martin 1X Well

19 20

21

ENE SS COPACABANA

23

2500

4

2000

5 24 26

27 28

2

14

15

AGUA CALIENTE 16

6

10

DST 10

29

30

31

LOWER NIA PRE K

7

17

3000

SHINAI

32

3

NOI PATSITE 8

ENE SS

DST 9

9

DST 8 ENE SS 18

22

8 6 5 7 4

9

GREEN SS

33

AMBO 10

DST 6

34

19

20

21

COPACABANA 3500 11

DST 4, 5 & 7 35 37

3 2

23

DST 2 & 3

THRUST FAULT

PICHA FAULT CHONTA A CALIENTE REPEAT

1

2500

LOWER NIA REPEAT SHINAI REPEAT

DST 1 12

Figure 3: Detailed section of the composite log across the reservoir section of the San Martin 1X Well

NOI PATSITE REPEAT TD

Figure 2: Composite log (Cretaceous to TD) of the San Martin 1X Well

APPENDIX 3l 1 of 2

San Martin 1X

Figure 4: Representative seismic line through the San Martin Structure. Note the large undrilled structure within the leading thrust sheet and the possibilities (rollover) that may be exist within the sub-thrust sheet The location of the seismic SH-UBA-22-39 is shown on the mapped displayed in Appendix 3f , Figure 3.

APPENDIX 3l 2 of 2

UCAYALI / ENE SEISMIC DATA BASE No 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43

Line-Name by PARSEP

Year

Shot for

Shot by

No Trace

Sp_a

Sp_z

segy

AC90-02 AC90-04 AC90-06 CHE96-1 CHE96-10 CHE96-11 CHE96-12 CHE96-13 CHE96-16 CHE96-17 CHE96-19A CHE96-19B CHE96-19D CHE96-2 CHE96-20 CHE96-21 CHE96-23 CHE96-24 CHE96-3 CHE96-4 CHE96-5 CHE96-6 CHE96-7 CHE96-8 CHE96-9

90

Petroleos del PCompañía Gene

2269

102

1236

mig

90

Petroleos del PCompañía Gene

1870

102

1036.5

mig

90

Petroleos del PCompañía Gene

967

102

585

mig

96

Crevron OversGrant Geophysic

2887

1001.5

2444.5

mig

96

Crevron OversGrant Geophysic

1267

1001.5

1634.5

mig

96

Crevron OversGrant Geophysic

1435

1001.5

1718.5

mig

96

Crevron OversGrant Geophysic

2041

1001.5

2021.5

mig

96

Crevron OversGrant Geophysic

3013

1001.5

2507.5

mig

96

Crevron OversGrant Geophysic

1411

1001.5

1706.5

mig

96

Crevron OversGrant Geophysic

1171

1001.5

1586.5

mig

96

Crevron OversGrant Geophysic

1513

1001.5

1757.25

mig

96

Crevron OversGrant Geophysic

1195

1001.5

1598.5

mig

96

Crevron OversGrant Geophysic

763

1001.5

1382.5

mig

96

Crevron OversGrant Geophysic

913

1008.5

1464.5

mig

96

Crevron OversGrant Geophysic

2521

1001.5

2261.5

mig

96

Crevron OversGrant Geophysic

751

1001.5

1376.5

mig

96

Crevron OversGrant Geophysic

1885

1001.5

1943.5

mig

96

Crevron OversGrant Geophysic

2035

1009.5

2026.5

mig

96

Crevron OversGrant Geophysic

2197

1001.5

2099.5

mig

96

Crevron OversGrant Geophysic

1183

1001.5

1592.5

mig

96

Crevron OversGrant Geophysic

1915

1001.5

1958.5

mig

96

Crevron OversGrant Geophysic

1135

1001.5

1568.5

mig

96

Crevron OversGrant Geophysic

1837

967.5

1885.5

mig

96

Crevron OversGrant Geophysic

775

1001.5

1388.5

mig

96

Crevron OversGrant Geophysic

985

1155.5

1647

mig

CHE98-30_96-19C CHE98-31 CHE98-32 CHE98-33 CHE98-34 CHE98-35 CHE98-36 CP739801 CP739802 CP739803 CP739804 CP739805 CP739806 CP739807 DX-103 DX-59 ELF96-01 ELF96-02

98

Crevron OversCompañía Gene

1339

1001.5

1670.5

mig

98

Crevron OversCompañía Gene

793

1001.5

1398

mig

98

Crevron OversCompañía Gene

925

1001.5

1463.5

mig

98

Crevron OversCompañía Gene

793

1001.5

1397.5

mig

98

Crevron OversCompañía Gene

661

1001.5

1331.5

mig

98

Crevron OversCompañía Gene

895

1001.5

1448.5

mig

98

Crevron OversCompañía Gene

859

1001.5

1430.5

mig

98

Coastal Perú Western Geophy

4068

101

2135.5

mig

98

Coastal Perú Western Geophy

3564

101

1883.5

mig

98

Coastal Perú Western Geophy

2773

101

1488

mig

98

Coastal Perú Western Geophy

3420

1811.5

103.5

mig

98

Coastal Perú Western Geophy

1346

774.5

102

mig

98

Coastal Perú Western Geophy

1985

1094

103.5

mig

98

Coastal Perú Western Geophy

1009

101

606

mig

73_74 Deminex

Petty Ray Geoph

612

267

573

mig

73_74 Deminex

Petty Ray Geoph

395

57

254.5

mig

96-97

ELF HYDROC Compañía Gene

6151

3225

6300

mig

96-97

ELF HYDROC Compañía Gene

9271

2329

6964

mig

Page 1

Well

Km

28.312 23.231 11.985 43.198 18.898 21.331 30.601 45.000 21.033 17.399 22.500 17.701 11.399 13.482 37.805 11.092 28.202 30.304 32.710 17.703 28.505 16.801 27.304 11.400 14.698 20.157 11.699 13.800 11.701 9.899 13.200 12.900 52.173 44.479 34.501 42.500 16.758 24.749 12.500 39.402 24.973 23.210 34.260

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

EP20782_03_CGG-AC-90-02.sgyqc EP20782_05_CGG-AC-90-04.sgyqc EP20782_06_CGG-AC-90-06.sgyqc EP20089_01_CHE-PE96-001.sgy EP20089_10_CHE-PE96-010.sgy EP20089_11_CHE-PE96-011.sgy EP20089_12_CHE-PE96-012.sgy EP20089_13_CHE-PE96-013.sgy EP20089_14_CHE-PE96-016.sgy EP20089_15_CHE-PE96-017.sgy EP20089_16_CHE-PE96-019A.sgy EP20089_17_CHE-PE96-019B.sgy EP20089_19_CHE-PE96-019D.sgy EP20089_02_CHE-PE96-002.sgy EP20089_20_CHE-PE96-020.sgy EP20089_21_CHE-PE96-021.sgy EP20089_22_CHE-PE96-023.sgy EP20089_23_CHE-PE96-024.sgy EP20089_03_CHE-PE96-003.sgy EP20089_04_CHE-PE96-004.sgy EP20089_05_CHE-PE96-005.sgy EP20089_06_CHE-PE96-006.sgy EP20089_07_CHE-PE96-007.sgy EP20089_08_CHE-PE96-008.sgy EP20089_09_CHE-PE96-009.sgy EP20103_07_CHE-PE98-030_PE96019C.sgy EP20103_01_CHE-PE96-031.sgy EP20103_02_CHE-PE96-032.sgy EP20103_03_CHE-PE96-033.sgy EP20103_04_CHE-PE96-034.sgy EP20103_05_CHE-PE96-035.sgy EP20103_06_CHE-PE96-036.sgy EP20580_09_COA-CP73-9801.sgy EP20580_10_COA-CP73-9802.sgy EP20580_11_COA-CP73-9803.sgy EP20580_12_COA-CP73-9804.sgy EP20580_13_COA-CP73-9805.sgy EP20580_14_COA-CP73-9806.sgy EP20580_15_COA-CP73-9807.sgy EP20546_DX-103.sgy EP20546_DX-59.sgy EP20175_20_ELF-ENE96-01.sgy EP20175_21_ELF-ENE96-02.sgy

Survey name by PERUPETRO (Navigation too)

PPCGG90L31L35 PPCGG90L31L35 PPCGG90L31L35 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHEGRG96L52 CHECGG98L52 CHECGG98L52 CHECGG98L52 CHECGG98L52 CHECGG98L52 CHECGG98L52 CHECGG98L52 COAWG98L73 COAWG98L73 COAWG98L73 COAWG98L73 COAWG98L73 COAWG98L73 COAWG98L73 DEXPRY7375L12 DEXPRY7375L13 ELFCGG9697L66 ELFCGG9697L66

No 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89

Line-Name by PARSEP

Year

Shot for

Shot by

No Trace

Sp_a

Sp_z

segy

ELF96-03 ELF96-05 ELF96-07 ELF96-09 ELF96-11 ELF96-12 ELF96-13 ELF97-105 G31-1000 G31-1001A G31-1001B G31-1001C G31-1002 G31-1003 G31-1003A G31-1004 G31-1006 G31-1006A G31-1008 G31-1010 G31-1012 G31-1014 G31-1016 G31-1022 G31-1070 G31-1086 G31-1094 G31-158E G31-158W G31-162 G31-163 G31-167 G31-413EXT G31-414 G31-416 G31-419EXT G31-425 G31-429 G31-431 G31-432 G31-433 G31-434 G31-435 G31-441 G31-442 G31-445

96-97

ELF HYDROC Compañía Gene

6151

4061

7136

mig

96-97

ELF HYDROC Compañía Gene

9121

1001

5561

mig

96-97

ELF HYDROC Compañía Gene

8221

1001

5111

mig

96-97

ELF HYDROC Compañía Gene

9211

1001

5606

mig

96-97

ELF HYDROC Compañía Gene

2262

1018

2148.5

mig

96-97

ELF HYDROC Compañía Gene

3211

1001

2606

mig

96-97

ELF HYDROC Compañía Gene

10561

993

6273

mig

96-97

ELF HYDROC Compañía Gene

8009

1001

5005

mig

81-82

Petroleos del PGeophysical Ser

581

965

1255

mig

81-82

Petroleos del PGeophysical Ser

900

2538.5

2090.5

mig

81-82

Petroleos del PGeophysical Ser

1037

1693

2211

mig

81-82

Petroleos del PGeophysical Ser

1637

911

1729

mig

81-82

Petroleos del PGeophysical Ser

472

991

1226.5

mig

81-82

Petroleos del PGeophysical Ser

1223

1661

1001

mig

81-82

Petroleos del PGeophysical Ser

588

1294.5

1002.5

mig

81-82

Petroleos del PGeophysical Ser

465

983

1215

mig

81-82

Petroleos del PGeophysical Ser

1085

971

1513

mig

81-82

Petroleos del PGeophysical Ser

389

992

1186

mig

81-82

Petroleos del PGeophysical Ser

957

1005

1483

mig

Pisqui_1X

81-82

Petroleos del PGeophysical Ser

985

1026.5

1518.5

mig

Coninca_2

81-82

Petroleos del PGeophysical Ser

405

1001

1203

mig

81-82

Petroleos del PGeophysical Ser

405

1002

1204

mig

81-82

Petroleos del PGeophysical Ser

677

1001

1339

mig

81-82

Petroleos del PGeophysical Ser

665

1005

1337

mig

81-82

Petroleos del PGeophysical Ser

389

1158

1352

mig

81-82

Petroleos del PGeophysical Ser

725

1001

1363

mig

81-82

Petroleos del PGeophysical Ser

1101

1017

1567

mig

74-76

Petroleos del PGeophysical Ser

516

1094

1351.5

mig

74-76

Petroleos del PGeophysical Ser

251

992

1117

mig

Aguaytía_2

74-76

Petroleos del PGeophysical Ser

251

992.5

1117.5

mig

Aguaytía_

74-76

Petroleos del PGeophysical Ser

251

992

1117

mig

74-76

Petroleos del PGeophysical Ser

423

1002

1213

mig

74-76

Petroleos del PGeophysical Ser

171

916

1001

mig

74-76

Petroleos del PGeophysical Ser

647

992

1315

mig

74-76

Petroleos del PGeophysical Ser

649

992

1316

mig

74-76

Petroleos del PGeophysical Ser

576

1962

2249.5

mig

74-76

Petroleos del PGeophysical Ser

1709

810

1664

mig

74-76

Petroleos del PGeophysical Ser

447

994

1217

mig

74-76

Petroleos del PGeophysical Ser

595

1006

1303

mig

74-76

Petroleos del PGeophysical Ser

310

968

1122.5

mig

74-76

Petroleos del PGeophysical Ser

304

970.5

1122

mig

74-76

Petroleos del PGeophysical Ser

369

954

1138

mig

74-76

Petroleos del PGeophysical Ser

205

1275.5

1173.5

mig

74-76

Petroleos del PGeophysical Ser

903

1150.5

1601.5

mig

74-76

Petroleos del PGeophysical Ser

803

1216.5

1617.5

mig

74-76

Petroleos del PGeophysical Ser

1427

1004

1717

mig

Page 2

Well

Oxapampa

Pisqui_1X

Cashiboya

Aguaytía_

Cashiboya

Cashiboya

Km

22.580 34.240 31.370 34.600 34.220 11.810 39.610 34.920 14.037 21.404 24.711 39.653 11.078 30.250 14.389 10.972 26.321 9.182 23.248 24.062 9.476 9.538 16.057 16.447 9.451 17.826 26.805 30.598 11.882 11.767 11.770 20.555 7.914 31.708 32.137 34.078 84.922 21.728 28.716 18.530 18.535 17.832 9.948 44.705 39.819 70.814

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

EP20175_22_ELF-ENE96-03.sgy EP20175_23_ELF-ENE96-05.sgy EP20175_24_ELF-ENE96-07.sgy EP20175_25_ELF-ENE96-09.sgy EP20175_04_ELF-ENE96-11.sgy EP20175_27_ELF-ENE96-12.sgy EP20175_28_ELF-ENE96-13.sgy EP20175_31_ELF-ENE97-105.sgy EP20625_01_G31-1000.sgy EP20623_02_G31-1001A.sgy EP20623_03_G31-1001B.sgy EP20342_06_G31-1001C.sgy EP20342_07_G31-1002.sgy EP20164_1_G31-1003.sgyqc EP20162_1_G31-1003A.sgyqc EP20625_06_G31-1004.sgy EP20342_09_G31-1006.sgy EP20625_08_G31-1006A.sgy EP20342_10_G31-1008.sgy EP20342_11_G31-1010.sgy EP20625_10_G31-1012.sgy EP20625_11_G31-1014.sgy EP20625_12_G31-1016.sgy EP20162_2_G31-1022.sgyqc EP20584_27_G31-1070.sgyqc EP20162_3_G31-1086.sgyqc EP20625_13_G31-1094.sgyqc EP20625_14_G31-158E.sgyqc EP20626_14_G31-158W.sgyqc EP20342_15_G31-162.sgyqc EP20625_15_G31-163.sgyqc EP20782_02_G31-167.sgyqc EP20775_1_G31-413EXT.sgyqc EP20782_07_G31-414.sgyqc EP20782_08_G31-416.sgyqc EP20342_18_G31-419EXT.sgyqc EP20162_5_G31-425.sgyqc EP20163_1_G31-429.sgyqc EP20162_4_G31-431.sgyqc EP20546_028_G31-432.sgyqc EP20546_031_G31-433.sgyqc EP20546_034_G31-434.sgyqc EP20546_037_G31-435.sgyqc EP20546_040_G31-441.sgyqc EP20547_18_G31-442.sgyqc EP20775_2_G31-445.sgyqc

Survey name by PERUPETRO (Navigation too)

ELFCGG9697L66 ELFCGG9697L66 ELFCGG9697L66 ELFCGG9697L66 ELFCGG9697L66 ELFCGG9697L66 ELFCGG9697L66 ELFCGG9697L66 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35

No

Line-Name by PARSEP

Year

G31-448N G31-448S G31-449 G31-450 G31-459 G35-1011A G35-1011B G35-1052 G35-1056 G35-1082 G35-1084 G35-600 G35-601 G35-602 G35-603

74-76

Petroleos del PGeophysical Ser

587

922

74-76

Petroleos del PGeophysical Ser

407

1238

74-76

Petroleos del PGeophysical Ser

795

992

1389

mig

74-76

Petroleos del PGeophysical Ser

1047

992

1515

mig

74-76

Petroleos del PGeophysical Ser

340

1153.5

984

mig

81-82

Petroleos del PGeophysical Ser

476

1228.5

991.5

mig

81-82

Petroleos del PGeophysical Ser

516

1264.5

1009.5

mig

81-82

Petroleos del PGeophysical Ser

691

991

1336

mig

81-82

Petroleos del PGeophysical Ser

521

991

1251

mig

81-82

Petroleos del PGeophysical Ser

607

992

1295

mig

81-82

Petroleos del PGeophysical Ser

523

991

1252

mig

74-76

Petroleos del PGeophysical Ser

572

1026

1311.5

mig

74-76

Petroleos del PGeophysical Ser

1122

1006

1566.5

mig

74-76

Petroleos del PGeophysical Ser

1137

1010

1578

mig

74-76

Petroleos del PGeophysical Ser

959

992

1471

mig

San_Aleja

74-76

Petroleos del PGeophysical Ser

1039

1400

1919

mig

Chonta

74-76

Petroleos del PGeophysical Ser

671

1992

2327

mig

74-76

Petroleos del PGeophysical Ser

523

1368

1629

mig

74-76

Petroleos del PGeophysical Ser

825

1993

2405

mig

74-76

Petroleos del PGeophysical Ser

439

1364

1583

mig

74-76

Petroleos del PGeophysical Ser

775

2012

2399

mig

74-76

Petroleos del PGeophysical Ser

627

1184

1497

mig

74-76

Petroleos del PGeophysical Ser

271

2090

2225

mig

74-76

Petroleos del PGeophysical Ser

519

2192

2451

mig

74-76

Petroleos del PGeophysical Ser

343

1050

1221

mig

74-76

Petroleos del PGeophysical Ser

833

997

1413

mig

74-76

Petroleos del PGeophysical Ser

753

1006

1382

mig

74-76

Petroleos del PGeophysical Ser

2088

2035.5

992.5

mig

74-76

Petroleos del PGeophysical Ser

763

1373

992

mig

74-76

Petroleos del PGeophysical Ser

1024

2845.5

2334.5

mig

74-76

Petroleos del PGeophysical Ser

379

980

1169

mig

74-76

Petroleos del PGeophysical Ser

487

992

1235

mig

74-76

Petroleos del PGeophysical Ser

545

1005

1277

mig

74-76

Petroleos del PGeophysical Ser

456

1297.5

1070.5

mig

74-76

Petroleos del PGeophysical Ser

523

980

1241

mig

74-76

Petroleos del PGeophysical Ser

483

1000

1241

mig

74-76

Petroleos del PGeophysical Ser

483

995

1236

mig

127

G35-604E_EXT G35-604W G35-605E G35-605W G35-606E G35-606W G35-607E G35-607W G35-608E G35-608W G35-609 G35-610 G35-612 G35-613N G35-613S G35-614 G35-615 G35-616 G35-617 G35-618 G35-619 G35-620 G35-621

74-76

Petroleos del PGeophysical Ser

583

992

1283

mig

63.541 40.189 32.123 50.278 25.596 46.517 38.140 15.930 30.908 20.831 50.421 45.254 127.960 46.248 62.414 21.962 29.255 31.894 26.211 32.022 29.620 29.664 36.194

128

G97W84-1

97

Anadarko

Western Geophy

5325

101

2763

mig

66.503

129

G97W84-2

97

Anadarko

Western Geophy

2542

101

1371.5

mig

31.764

130

G97W84-3

97

Anadarko

Western Geophy

3114

101

1657.5

mig

39.001

90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126

Shot for

Shot by

No Trace

Sp_a

Sp_z

segy

Well

1215

mig

Neshuya_

1441

mig

Page 3

Km

28.848 20.002 38.693 51.784 19.826 11.242 12.200 16.743 12.820 14.708 12.802 34.260 68.553 70.019 57.308

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

EP20775_3_G31-448N.sgyqc EP20775_4_G31-448S.sgyqc EP20775_5_G31-449.sgyqc EP20775_6_G31-450.sgyqc EP20775_7_G31-459.sgyqc EP20782_11_G35-1011A.sgyqc EP20123_12_G35-1011B.sgyqc EP20782_12_G35-1052.sgyqc EP20782_13_G35-1056.sgyqc EP20782_14_G35-1082.sgyqc EP20782_15_G35-1084.sgyqc EP20626_04_G35-600.sgy EP20782_09_G35-601.sgyqc EP20779_01_G35-602.sgyqc EP20779_02_G35-603.sgyqc EP20123_04_G35604E_604EXT.sgyqc EP20779_04_G35-604W.sgyqc EP20782_10_G35-605E.sgyqc EP20779_05_G35-605W.sgyqc EP20779_06_G35-606E.sgyqc EP20779_07_G35-606W.sgyqc EP20779_08_G35-607E.sgyqc EP20779_09_G35-607W.sgyqc EP20777_1_G35-608E.sgyqc EP20777_2_G35-608W.sgyqc EP20777_3_G35-609.sgyqc EP20777_4_G35-610.sgyqc EP20787_1_G35-612.sgyqc EP20123_05_G35-613N.sgyqc EP20777_7_G35-613S.sgyqc EP20626_05_G35-614.sgy EP20626_06_G35-615.sgy EP20626_07_G35-616.sgyqc EP20626_02_G35-617.sgy EP20123_06_G35-618.sgyqc EP20123_07_G35-619.sgyqc EP20123_08_G35-620.sgyqc EP20777_9_G35-621.sgyqc line1_segy_final_mig_filtered_scaled_ stack line2_segy_final_mig_filtered_scaled_ stack line3_segy_final_mig_filtered_scaled_ stack

Survey name by PERUPETRO (Navigation too)

PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI8182L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 PPGSI7476L31L35 ANAWG97L84 ANAWG97L84 ANAWG97L84

No

Line-Name by PARSEP

131

G97W84-4

97

Anadarko

Western Geophy

6579

101

3390

mig

132

G97W84-5

97

Anadarko

Western Geophy

3543

127

1898

mig

133

G97W84-6

97

Anadarko

Western Geophy

10319

101

5260

mig

134

G97W84-7

97

Anadarko

Western Geophy

6953

101

3577

mig

135

G97W84-8

97

Anadarko

Western Geophy

5292

101

2746.5

mig

136

G97W84-9 H-1 H-2 H-3 H-4 H-5 H-6 H-7 H-8 H90-01 H90-02 H90-03 H90-04 H90-06 H90-10 HIS-08A HIS-08B HIS-09 HIS-11 HIS-12A HIS-12B HIS-13 HIS-15 HIS-17 HIS-19 HIS-20 HIS-21 HIS-23 HIS-27NE HIS-27SW HIS-27W HIS-29NE HIS-33 HIS-35 IN9501

97

Anadarko

Western Geophy

6843

101

3522

mig

80

Petroleos del PGeophysical Ser

223

101

212

mig

137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170

Year

Shot for

Shot by

No Trace

Sp_a

Sp_z

segy

80

Petroleos del PGeophysical Ser

220

101

211.5

mig

81-82

Petroleos del PGeophysical Ser

1429

1745

2460

mig

81-82

Petroleos del PGeophysical Ser

259

1006

1137

mig

81-82

Petroleos del PGeophysical Ser

799

1006

1405

mig

81-82

Petroleos del PGeophysical Ser

337

1032

1202

mig

81-82

Petroleos del PGeophysical Ser

327

1040

1203

mig

81-82

Petroleos del PGeophysical Ser

473

1076

1312

mig

90

Petroleos del PCompañía Gene

1310

103

757.5

mig

90

Petroleos del PCompañía Gene

980

102

591.5

mig

90

Petroleos del PCompañía Gene

914

94

550.5

mig

90

Petroleos del PCompañía Gene

991

86

581

mig

90

Petroleos del PCompañía Gene

804

265

666.5

mig

90

Petroleos del PCompañía Gene

881

101

541

mig

73-75

Hispanoil

Geophysical Ser

215

338.5

445.5

mig

73-75

Hispanoil

Geophysical Ser

1167

430

1013

mig

73-75

Hispanoil

Geophysical Ser

967

902.5

1385.5

mig

73-75

Hispanoil

Geophysical Ser

1945

407

1379

mig

73-75

Hispanoil

Geophysical Ser

389

502.5

696.5

mig

73-75

Hispanoil

Geophysical Ser

359

690.5

869.5

mig

73-75

Hispanoil

Geophysical Ser

767

978.5

1361.5

mig

73-75

Hispanoil

Geophysical Ser

1921

395

1355

mig

73-75

Hispanoil

Geophysical Ser

963

852.5

1333.5

mig

73-75

Hispanoil

Geophysical Ser

735

790.5

1157.5

mig

73-75

Hispanoil

Geophysical Ser

951

597.5

1072.5

mig

73-75

Hispanoil

Geophysical Ser

1015

550

1057

mig

73-75

Hispanoil

Geophysical Ser

819

408

817

mig

73-75

Hispanoil

Geophysical Ser

979

600

1089

mig

73-75

Hispanoil

Geophysical Ser

451

382

607

mig

73-75

Hispanoil

Geophysical Ser

303

395

546

mig

73-75

Hispanoil

Geophysical Ser

191

900.5

995.5

mig

73-75

Hispanoil

Geophysical Ser

589

522.5

816.5

mig

73-75

Hispanoil

Geophysical Ser

643

502

823

mig

Coastal oil andGrant Geophysic

1331

1001

1666.5

mig

95

Page 4

Well

Platanal_1

Maquía_1X

Shahuinto_ Runuya_1

Km

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

line4_segy_final_mig_filtered_scaled_ 82.002 stack line5_segy_final_mig_filtered_scaled_ 44.258 stack line6_segy_final_mig_filtered_scaled_ 128.756 stack line7_segy_final_mig_filtered_scaled_ 86.754 stack line8_segy_final_mig_filtered_scaled_ 66.019 stack line9_segy_final_mig_filtered_scaled_ 85.508 stack 10.874 20929_09_H-1.sgy 10.924 20929_10_H-2.sgy 56.970 20929_11_H-3.sgy 6.454 20929_12_H-4.sgy 19.435 20929_13_H-5.sgy 8.550 20929_15_H-6.sgy 8.082 20929_16_H-7.sgy 11.359 20929_17_H-8.sgy 16.239 20929_18_H-90-01.sgy 12.227 20929_19_H-90-02.sgy 11.232 20930_01_H-90-03.sgy 12.294 20930_02_H-90-04.sgy 10.086 20930_03_H-90-06.sgy 11.031 20930_04_H-90-10.sgy 11.947 EP20334_03_HIS-08.sgyqc 67.732 EP20334_04_HIS-08.sgyqc 56.700 EP20334_05_HIS-09.sgyqc 114.264 EP20602_07_HIS-11.sgyqc 22.412 EP20336_01_HIS-12.sgy 19.797 EP20336_02_HIS-12.sgy 43.856 EP20336_03_HIS-13.sgy 113.314 EP20602_16_HIS-15.sgyc 55.280 EP20334_06_HIS-17.sgy 42.381 EP20334_07_HIS-19.sgy 54.155 EP20334_08_HIS-20.sgyqc 58.554 EP20334_09_HIS-21.sgy 46.004 EP20334_10_HIS-23.sgy 56.572 EP20652_08_HIS-27NE.sgyqc 26.609 EP20652_09_HIS-27NE.sgyqc 18.218 EP20602_30_HIS-27W.sgyqc 10.570 EP20334_11_HIS-29NE.sgyqc 33.880 EP20336_05_HIS-33.sgyqc 37.171 EP20652_10_HIS-35.sgyqc 13.385 EP20546_076_COA-IN-95-01.sgyc

Survey name by PERUPETRO (Navigation too)

ANAWG97L84 ANAWG97L84 ANAWG97L84 ANAWG97L84 ANAWG97L84 ANAWG97L84 PPSIS80L16A PPSIS80L16A PPGSI8182L16A PPGSI8182L16A PPGSI8182L16A PPGSI8182L16A PPGSI8182L16A PPGSI8182L16A PPCGG90L16A PPCGG90L16A PPCGG90L16A PPCGG90L16A PPCGG90L16A PPCGG90L16A HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 HISGSI7375L36 COAGRG95L74

171

IN9502

95

Coastal oil andGrant Geophysic

2087

1001

2044.5

mig

20.798 EP20546_079_COA-IN-95-02.sgyc

COAGRG95L74

172

MP97-01

97

Mapple

Veritas

1279

740

102.5

mig

15.750 CDP20127_1_MAP-MP-01-97.sgyqc

MAPVER97L31D

173

MP97-02

97

Mapple

Veritas

839

520

102.5

mig

MP97-03

97

Mapple

Veritas

1231

101

716

mig

10.250 CDP20127_2_MAP-MP-02-97.sgyqc 15.247 CDP20127_3_MAP-MP-03-97.sgyqc

MAPVER97L31D

174 175

MP97-04

97

Mapple

Veritas

878

481.5

44

mig

10.750 CDP20127_4_MAP-MP-04-97.sgyqc

MAPVER97L31D

176

MP97-05

97

Mapple

Veritas

1042

621.5

101.5

mig

MAPVER97L31D

177

MP97-06 NP-10 NP-11 NP-12 NP-14 NP-15 NP-16 NP-20 NP-23 NP-24 NP-28 NP-29 NP-30 NP-31 NP-32 NP-33 NP-34 NP-35 NP-36 NP-7 NP-8 NP-9 OR9505 OR9506 OR9507 OR9508 OR9509 OR9510 OR9511 OR9512 OR9513 OXY36-1 OXY36-11_7 OXY36-12_4 OXY36-13_7 OXY36-17_5 OXY36-18 OXY36-18E

97

Mapple

Veritas

839

520

102.5

mig

83

Petroleos del PNorpac

789

74

468

mig

83

Petroleos del PNorpac

543

74

345

mig

83

Petroleos del PNorpac

669

408

74

mig

83-84

Petroleos del PNorpac

903

75

526

mig

83-84

Petroleos del PNorpac

1103

75

626

mig

83-84

Petroleos del PNorpac

709

429

75

mig

83-84

Petroleos del PNorpac

825

75

486.5

mig

74-86

Petroleos del PGeophysical Ser

707

73.5

426.5

mig

74-87

Petroleos del PGeophysical Ser

1379

73.5

688.5

mig

83-84

Petroleos del PNorpac

691

75

420

mig

83-84

Petroleos del PNorpac

997

471

969

mig

83-84

Petroleos del PNorpac

541

75

345

mig

83-84

Petroleos del PNorpac

545

75

347

mig

83-84

Petroleos del PNorpac

873

75

511

mig

83-84

Petroleos del PNorpac

1199

101

700

mig

83-84

Petroleos del PNorpac

1189

75

669

mig

83-84

Petroleos del PNorpac

1765

75

957

mig

83-84

Petroleos del PNorpac

1561

73

853

mig

83

Petroleos del PNorpac

243

207

328

mig

83

Petroleos del PNorpac

669

74

408

mig

83

Petroleos del PNorpac

789

74

468

mig

95

Coastal oil andGrant Geophysic

3291

1001

2646.5

mig

95

Coastal oil andGrant Geophysic

4103

1001

3052.5

mig

95

Coastal oil andGrant Geophysic

2773

1001

2387.5

mig

95

Coastal oil andGrant Geophysic

3333

1001

2667.5

mig

95

Coastal oil andGrant Geophysic

4425

1001

3213.5

mig

95

Coastal oil andGrant Geophysic

4957

1001

3479.5

mig

95

Coastal oil andGrant Geophysic

2661

1301

2631.5

mig

95

Coastal oil andGrant Geophysic

2563

1001

2282.5

mig

95

Coastal oil andGrant Geophysic

2701

2351.5

1007.5

mig

87-88

Occidental PetWestern Geophy

3557

1878

101.5

mig

87-88

Occidental PetWestern Geophy

2697

2228

880.5

mig

87-88

Occidental PetWestern Geophy

2021

1093

86.5

mig

87-88

Occidental PetWestern Geophy

2401

2080

881

mig

87-88

Occidental PetWestern Geophy

5225

2643

36

mig

87-88

Occidental PetWestern Geophy

3721

2520

661

mig

87-88

Occidental PetWestern Geophy

5203

3880

1284

mig

12.998 CDP20127_5_MAP-MP-05-97.sgyqc 10.249 CDP20127_6_MAP-MP-06-97.sgyqc 19.134 EP20582_02_NP-10.sgyqc 13.304 20930_06_NP-11.sgy 16.365 EP20581_21_NP-12.sgyqc 21.988 EP20626_08_NP-14.sgy 27.027 EP20626_09_NP-15.sgy 17.105 EP20626_10_NP-16.sgy 20.010 EP20626_11_NP-20.sgyqc 16.855 EP20626_12_NP-23.sgy 29.505 EP20626_13_NP-24.sgy 16.740 EP20123_10_NP-28.sgyqc 23.635 EP20773_1_NP-29.sgyqc 12.580 EP20773_2_NP-30.sgyqc 13.171 EP20773_3_NP-31.sgyqc 20.717 EP20773_4_NP-32.sgyqc 28.311 EP20773_5_NP-33.sgyqc 29.031 EP20773_6_NP-34.sgyqc 42.432 EP20773_7_NP-35.sgyqc 37.398 EP20782_01_NP-36.sgyqc 5.937 EP20582_05_NP-7.sgyqc 16.000 EP20582_08_NP-8.sgyqc 19.025 EP20581_18_NP-9.sgyqc 32.994 EP20583_02_COA-OR-95-05.sgyc 40.988 EP20583_05_COA-OR-95-06.sgyc 27.598 EP20581_02_COA-OR-95-07.sgy 33.190 EP20581_05_COA-OR-95-08.sgy 44.189 EP20546_100_COA-OR-95-09.sgyc 49.401 EP20546_COA-OR-95-10.sgyc 26.594 EP20546_COA-OR-95-11.sgyc 25.588 EP20546_COA-OR-95-12.sgyc 26.803 EP20546_COA-OR-95-13.sgyc 43.256 EP20634_05_OXY36-1.sgyc 32.597 EP20634_12_OXY36-11_7.sgy 24.610 EP20634_13_OXY36-12_4.sgyqc 29.069 EP20634_14_OXY36-13_7.sgyc 63.830 EP20634_15_OXY36-17_5.sgyc 44.967 EP20634_16_OXY36-18.sgyqc 64.232 EP20634_17_OXY36-18E.sgyqc

179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214

Shot for

Shot by

No Trace

Sp_a

Sp_z

segy

Page 5

Well

Agua_Cali

Agua_Cali

Tahuaya_

Rashaya

Chío_1X

Santa_Cla

Km

Survey name by PERUPETRO (Navigation too)

Line-Name by PARSEP

178

Year

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

No

MAPVER97L31D

MAPVER97L31D PPNP83L16A PPNP83L16A PPNP83L16A PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP8384L31L35 PPNP83L16A PPNP83L16A PPNP83L16A COAGRG95L74 COAGRG95L74 COAGRG95L74 COAGRG95L74 COAGRG95L74 COAGRG95L74 COAGRG95L74 COAGRG95L74 COAGRG95L74 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36

No

Line-Name by PARSEP

Year

215

87-88

Occidental PetWestern Geophy

1787

993

87-88

Occidental PetWestern Geophy

1211

705

87-88

Occidental PetWestern Geophy

1771

87-88

Occidental PetWestern Geophy

1025

87-88

Occidental PetWestern Geophy

87-88

252

OXY36-20_4 OXY36-21_5 OXY36-22 OXY36-23_5 OXY36-28_6 OXY36-29 OXY36-3 OXY36-33 OXY36-35_1 OXY36-5_7 OXY36-5_7E OXY36-55 OXY36-7_9 OXY36-7_9EXT OXY36-9_7 PC-1 PC-2 PC-3 PC-4 PC-5 PC-6 PC-7 PC-8 PC-9 PH9503 REP34-101 REP34-102 REP34-103 REP34-104 REP34-106 REP34-108 REP34-110 REP34-112 REP34-114 REP34-116 REP34-118 REP34-120 REP34-122

102

mig

La-Colpa_

100

mig

985

105

mig

612

100.5

mig

3625

1896

86.5

mig

Occidental PetWestern Geophy

1449

824

103.5

mig

87-88

Occidental PetWestern Geophy

2947

1673

204.5

mig

87-88

Occidental PetWestern Geophy

833

516

102

mig

87-88

Occidental PetWestern Geophy

1211

720

115

mig

87-88

Occidental PetWestern Geophy

1565

947

166

mig

87-88

Occidental PetWestern Geophy

2090

1999.5

960

mig

87-88

Occidental PetWestern Geophy

1439

819

104

mig

87-88

Occidental PetWestern Geophy

2072

1925.5

893.5

mig

87-88

Occidental PetWestern Geophy

1751

940

65.5

mig

87-88

Occidental PetWestern Geophy

2473

2116

884

mig

74-88

Petroleos del PGeophysical Ser

205

100

5200

mig

74-89

Petroleos del PGeophysical Ser

337

100

8500

mig

74-90

Petroleos del PGeophysical Ser

455

11450

100

mig

74-91

Petroleos del PGeophysical Ser

291

100

7300

mig

74-92

Petroleos del PGeophysical Ser

285

100

7200

mig

74-93

Petroleos del PGeophysical Ser

325

100

8200

mig

74-94

Petroleos del PGeophysical Ser

307

100

7700

mig

74-95

Petroleos del PGeophysical Ser

325

100

8200

mig

74-96

Petroleos del PGeophysical Ser

265

100

6700

mig

95

Coastal oil andGrant Geophysic

1961

1001

1981

mig

99

Repsol

Compañía Gene

3196

101

1698.5

mig

99

Repsol

Compañía Gene

1432

101

816.5

mig

99

Repsol

Compañía Gene

3034

101

1617.5

mig

99

Repsol

Compañía Gene

1351

102

777

mig

99

Repsol

Compañía Gene

1270

102

736.5

mig

99

Repsol

Compañía Gene

2395

101

1298

mig

99

Repsol

Compañía Gene

2872

101

1536.5

mig

99

Repsol

Compañía Gene

2872

101

1536.5

mig

99

Repsol

Compañía Gene

3196

101

1698.5

mig

99

Repsol

Compañía Gene

3196

101

1698.5

mig

99

Repsol

Compañía Gene

3592

101

1896.5

mig

99

Repsol

Compañía Gene

3511

101

1856

mig

99

Repsol

Compañía Gene

3358

102

1780.5

mig

21.897 14.822 21.806 12.538 44.234 17.684 36.168 9.943 14.610 19.052 25.567 17.655 24.724 21.340 29.998 5.012 8.012 11.176 6.931 6.996 7.936 7.511 8.056 6.523 19.624 39.751 17.751 37.749 16.751 15.751 29.751 35.748 35.751 39.747 39.748 44.748 43.749 41.751

253

REP35_34-105

99

Repsol

Compañía Gene

4555

102

2379

mig

56.748 EP20638_14_REP35_34-99-105.sgy

REPCGG99L34&35

254

REP35_34-107

99

Repsol

Compañía Gene

5914

102

3058.5

mig

73.749 EP20638_15_REP35_34-99-107.sgy

REPCGG99L34&35

255

REP35_34-111 REP35-101 257 REP35-109

99

Repsol

Compañía Gene

4078

102

2140.5

mig

256

99

Repsol

Compañía Gene

2845

116

1538

mig

99

Repsol

Compañía Gene

2800

103

1502.5

mig

50.748 EP20638_17_REP35_34-99-111.sgy 35.500 EP20638_13_REP35-99-101.sgy 34.752 EP20638_16_REP35-99-109.sgy

REPCGG99L34&35 REPCGG99L35 REPCGG99L35

218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251

No Trace

Sp_a

Sp_z

Page 6

Pacaya_1X Inuya_1X

Km

Survey name by PERUPETRO (Navigation too)

Well

217

Shot by

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

segy

216

Shot for

EP20634_18_OXY36-20_4.sgyc EP20634_19_OXY36-21_5.sgyqc EP20634_20_OXY36-22.sgyc EP20634_21_OXY36-23_5.sgyqc EP20634_23_OXY36-28_6.sgy EP20634_24_OXY36-29.sgyqc EP20634_06_OXY36-3.sgyc EP20634_25_OXY36-33.sgyqc EP20634_26_OXY36-35_1.sgyqc EP20634_07_OXY36-5_7.sgyc EP20634_08_OXY36-5_7E.sgy EP20165_1_OXY36-55.sgyqc EP20634_09_OXY36-7_9.sgyc EP20634_10_OXY36-7_9EXT.sgyc EP20634_11_OXY36-9_7.sgyc EP20581_24_SIS79-PC-1.sgyqc EP20581_27_SIS80-PC-2.sgyqc EP20581_30_SIS80-PC-3.sgyqc EP20581_33_SIS80-PC-4.sgyqc EP20581_36_SIS80-PC-5.sgyqc EP20581_39_SIS80-PC-6.sgyqc EP20581_42_SIS80-PC-7.sgyqc EP20581_45_SIS80-PC-8.sgyqc EP20581_48_SIS80-PC-9.sgyqc EP20583_11_COA-PH-95-03.sgyc EP20634_27_REP34-99-101.sgy EP20634_28_REP34-99-102.sgy EP20634_29_REP34-99-103.sgy EP20634_30_REP34-99-104.sgy EP20634_32_REP34-99-106.sgy EP20634_34_REP34-99-108.sgy EP20634_35_REP34-99-110.sgy EP20634_37_REP34-99-112.sgy EP20634_38_REP34-99-114.sgy EP20634_39_REP34-99-116.sgy EP20634_40_REP34-99-118.sgy EP20634_41_REP34-99-120.sgy EP20634_42_REP34-99-122.sgy

OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 OXYWG8788L36 PPSIS80L31 PPSIS80L31 PPSIS80L31 PPSIS80L31 PPSIS80L31 PPSIS80L31 PPSIS80L31 PPSIS80L31 PPSIS80L31 COAGRG95L74 REPCGG99L34 REPCGG99L34 REPCGG99L34 REPCGG99L34 REPCGG99L34 REPCGG99L34 REPCGG99L34 REPCGG99L34 REPCGG99L34 REPCGG99L34 REPCGG99L34 REPCGG99L34 REPCGG99L34

258

99

Repsol

Compañía Gene

3673

101

1937

mig

99

Repsol

Compañía Gene

3835

103

2020

mig

99

Repsol

Compañía Gene

3835

103

2020

mig

99

Repsol

Compañía Gene

3916

103

2060.5

mig

99

Repsol

Compañía Gene

3997

102

2100

mig

99

Repsol

Compañía Gene

1594

103

899.5

mig

99

Repsol

Compañía Gene

3583

105

1896

mig

99

Repsol

Compañía Gene

1594

102

898.5

mig

266

REP35-124 REP35-126 REP35-128 REP35-130 REP35-132 REP35-134 REP35-136 REP35-138 SC9504

95

Coastal oil andGrant Geophysic

1673

989

1825

mig

45.749 47.746 47.748 48.750 49.749 19.748 44.751 19.750 16.598

267

SHL-UB-102

84

Shell

Seismograph

5356

1861

2396.5

mig

13.628 CP25185_06_SHL-UB-102.sgy

SHLSSL8485L38L42

268

SHL-UB-103

85

Shell

Seismograph

5356

1003

1538.5

mig

13.619 CP25185_05_SHL-UB-103.sgy

SHLSSL8485L38L42

269

SHL-UB-104

84

Shell

Seismograph

4969

1031

3515

mig

62.372 EP20638_06_SHL-UB-104.sgy

SHLSSL8485L38L42

270

SHL-UB-105

84

Shell

Seismograph

5383

1003.5

1541.7

mig

13.551 CP25961_09_SHL-UB-105.sgy

SHLSSL8485L38L42

271

SHL-UB-106

85

Shell

Seismograph

5455

1032

3759

mig

68.074 EP20638_07_SHL-UB-106.sgy

SHLSSL8485L38L42

272

SHL-UB-106B

85

Shell

Seismograph

523

832

1093

mig

273

SHL-UB-107

85

Shell

Seismograph

4366

1003

3185.5

mig

54.869 EP20638_08_SHL-UB-107.sgy

SHLSSL8485L38L42

274

SHL-UB-108

85

Shell

Seismograph

5905

1031

3983

mig

73.967 EP20642_04_SHL-UB-108.sgy

SHLSSL8485L38L42

275

SHL-UB-113

85

Shell

Seismograph

5356

2960

3495.5

mig

13.519 CP25960_18_SHL-UB-113.sgy

SHLSSL8485L38L42

276

SHL-UB-114

85

Shell

Seismograph

5429

1008.5

1551.3

mig

13.469 CP25961_02_SHL-UB-114.sgy

SHLSSL8485L38L42

277

SHL-UB-150

85

Shell

Seismograph

5401

1003.5

1543.5

mig

13.611 CP25961_05_SHL-UB-150.sgy

SHLSSL8485L38L42

278

SHL-UB-160

85

Shell

Seismograph

1891

1002

1947

mig

23.559 EP20602_38_SHL-UB-160.sgy

SHLSSL8485L38L42

279

SHL-UB-30

84

Shell

Seismograph

5491

1233.5

1782.5

mig

13.577 CP25185_08_SHL-UB-30.sgy

SHLSSL8485L38L42

280

SHL-UB-31

85

Shell

Seismograph

5475

1053

1600.4

mig

13.435 CP25185_07_SHL-UB-31.sgy

SHLSSL8485L38L42

281

SHL-UB-32

84

Shell

Seismograph

5383

1007.5

1545.7

mig

13.325 EP20340_07_SHL-UB-32.sgy

SHLSSL8485L38L42

282

SHL-UB-33

85

Shell

Seismograph

5475

1003.5

1550.9

mig

13.549 EP20340_06_SHL-UB-33.sgy

SHLSSL8485L38L42

283

SHL-UB-34A_15

84

Shell

Seismograph

5356

1000

1535.5

mig

13.634 CP25185_10_SHL-UB-34A_15.sgy

SHLSSL8485L38L42

284

SHL-UB-34B_B_15

85

Shell

Seismograph

5401

1000

1540

mig

13.654 CP25961_14_SHL-UB-34A_B_15.sgy SHLSSL8485L38L42

260 261 262 263 264 265

Shot for

Shot by

No Trace

Sp_a

Sp_z

segy

Page 7

Well

Armihua

Km

Survey name by PERUPETRO (Navigation too)

Line-Name by PARSEP

259

Year

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

No

EP20638_18_REP35-99-124.sgy EP20638_19_REP35-99-126.sgy EP20638_20_REP35-99-128.sgy EP20638_21_REP35-99-130.sgy EP20638_22_REP35-99-132.sgy EP20638_23_REP35-99-134.sgy EP20638_24_REP35-99-136.sgy EP20638_25_REP35-99-138.sgy EP20583_14_COA-SC-95-04.sgyc

6.434 EP20642_03_SHL-UB-106B.sgy

Sepa_1X

REPCGG99L35 REPCGG99L35 REPCGG99L35 REPCGG99L35 REPCGG99L35 REPCGG99L35 REPCGG99L35 REPCGG99L35 COAGRG95L74

SHLSSL8485L38L42

Year

Shot for

Shot by

No Trace

Sp_a

Sp_z

segy

Km

Survey name by PERUPETRO (Navigation too)

Line-Name by PARSEP

285

SHL-UB-35

85

Shell

Seismograph

5383

1003.5

1541.7

mig

13.559 CP25960_19_SHL-UB-35.sgy

SHLSSL8485L38L42

286

SHL-UB-36

84

Shell

Seismograph

5383

1003.5

1541.7

mig

13.559 EP20340_09_SHL-UB-36.sgy

SHLSSL8485L38L42

287

SHL-UB-38

84

Shell

Seismograph

5475

1003.5

1550.9

mig

13.558 EP20340_08_SHL-UB-38.sgy

SHLSSL8485L38L42

288

SHL-UB-40

84

Shell

Seismograph

5383

1003.5

1541.7

mig

13.556 EP20340_05_SHL-UB-40.sgy

SHLSSL8485L38L42

289

SHL-UB-42

85

Shell

Seismograph

5475

1002

1549.4

mig

13.799 CP25185_01_SHL-UB-42.sgy

SHLSSL8485L38L42

290

SHL-UB-44

85

Shell

Seismograph

5453

1002.5

1547.7

mig

13.231 CP25960_10_SHL-UB-44.sgy

SHLSSL8485L38L42

291

SHL-UB-45_45E

84

Shell

Seismograph

5401

1005

1545

mig

13.789 CP25961_12_SHL-UB-45_45E.sgy

SHLSSL8485L38L42

292

SHL-UB-45A

84

Shell

Seismograph

5429

1005

1547.8

mig

13.539 CP25960_11_SHL-UB-45A.sgy

SHLSSL8485L38L42

293

SHL-UB-46

84

Shell

Seismograph

5429

1010.5

1553.5

mig

13.495 CP25960_12_SHL-UB-46

SHLSSL8485L38L42

294

SHL-UB-47

84

Shell

Seismograph

5446

1043.5

1588

mig

13.586 CP25960_13_SHL-UB-47.sgy

SHLSSL8485L38L42

295

SHL-UB-48

84

Shell

Seismograph

5429

1003

1545.8

mig

13.384 CP25960_14_SHL-UB-48.sgy

SHLSSL8485L38L42

296

SHL-UB-49

84

Shell

Seismograph

5041

1003

1507

mig

12.564 CP25960_15_SHL-UB-49.sgy

SHLSSL8485L38L42

297

SHL-UB-50

84

Shell

Seismograph

5446

1002

1546.5

mig

13.625 CP25960_16_SHL-UB-50.sgy

SHLSSL8485L38L42

298

SHL-UB-51

84

Shell

Seismograph

5446

1010

1554.5

mig

13.671 CP25960_17_SHL-UB-51.sgy

SHLSSL8485L38L42

299

SHL-UB-52_09

85

Shell

Seismograph

5401

1000

1540

mig

13.612 CP25961_11_SHL-UB-52_09.sgy

SHLSSL8485L38L42

300

SHL-UB-54

84

Shell

Seismograph

5401

1012.5

1552.5

mig

13.595 CP25961_01_SHL-UB-54.sgy

SHLSSL8485L38L42

301

SHL-UB-56

84

Shell

Seismograph

5401

1034.5

1574.5

mig

13.686 CP25961_04_SHL-UB-56.sgy

SHLSSL8485L38L42

302

SHL-UB-58

84

Shell

Seismograph

2008

1003

2006.5

mig

25.477 EP20602_36_SHL-UB-58.sgy

SHLSSL8485L38L42

303

SHL-UB-59

85

Shell

Seismograph

4123

1010

3071

mig

51.599 EP20638_01_SHL-UB-59.sgy

SHLSSL8485L38L42

304

SHL-UB-595

85

Shell

Seismograph

1504

1013

1764.5

mig

18.718 EP20602_40_SHL-UB-595.sgy

SHLSSL8485L38L42

305

SHL-UB-60

85

Shell

Seismograph

3691

1003

2848

mig

46.075 EP20638_02_SHL-UB-60.sgy

SHLSSL8485L38L42

306

SHL-UB-61

85

Shell

Seismograph

8326

1007

5169.5

mig

104.478 EP20638_03_SHL-UB-61.sgy

SHLSSL8485L38L42

307

SHL-UB-615

85

Shell

Seismograph

1513

1037

1793

mig

Page 8

Well

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

No

18.818 EP20602_41_SHL-UB-615.sgy

SHLSSL8485L38L42

Year

Shot for

Shot by

No Trace

Sp_a

Sp_z

segy

308

SHL-UB-62

85

Shell

Seismograph

6616

1085

4392.5

mig

82.929 EP20642_01_SHL-UB-62.sgy

SHLSSL8485L38L42

309

SHL-UB-64

85

Shell

Seismograph

4510

1031

3285.5

mig

56.351 EP20642_02_SHL-UB-64.sgy

SHLSSL8485L38L42

310

SHL-UB-82

85

Shell

Seismograph

5401

1002.5

1542.5

mig

13.596 CP25961_10_SHL-UB-82.sgy

SHLSSL8485L38L42

311

SHL-UB-90

85

Shell

Seismograph

2404

1003

2204.5

mig

30.021 EP20638_04_SHL-UB-90.sgy

SHLSSL8485L38L42

312

SHL-UB-96

85

Shell

Seismograph

4132

1031

3096.5

mig

51.715 EP20638_05_SHL-UB-96.sgy

SHLSSL8485L38L42

313

SHL-UBA-01

82

Shell

Geosurce

2769

56

1440

mig

40.593 EP20638_09_SHL-UBA-01.sgy

SHLGE08283L38L42

314

SHL-UBA-02

82

Shell

Geosurce

2729

50

1414

mig

20.244 EP20601_10_SHL-UBA-02.sgy

SHLGE08283L38L42

315

SHL-UBA-03

82

Shell

Geosurce

21116

1009

3120.5

mig

58.886 CP25961_07_SHL-UBA-03B.sgy

SHLGE08283L38L42

316

SHL-UBA-03A

82

Shell

Geosurce

2977

3122

4610

mig

21.558 EP20638_10_SHL-UBA-03A.sgy

SHLGE08283L38L42

317

SHL-UBA-03E

82

Shell

Geosurce

15094

1003

2512.3

mig

44.288 CP25961_08_SHL-UBA-03E.sgy

SHLGE08283L38L42

318

SHL-UBA-04A

82

Shell

Geosurce

1921

1120

2080

mig

13.929 EP20638_11_SHL-UBA-04A.sgy

SHLGE08283L38L42

319

SHL-UBA-04B

82

Shell

Geosurce

3601

3054

4854

mig

26.626 EP20638_12_SHL-UBA-04B.sgy

SHLGE08283L38L42

320

SHL-UBA-05

82

Shell

Geosurce

1464

684

1415.5

mig

21.710 EP20599_82_SHL-UBA-05.sgy

SHLGE08283L38L42

321

SHL-UBA-06

82

Shell

Geosurce

33804

1056

4436.3

mig

50.257 CP25961_06_SHL-UBA-06.sgy

SHLGE08283L38L42

322

SHL-UBA-07

82

Shell

Geosurce

11441

912

2056

mig

32.859 CP25960_01_SHL-UBA-07.sgy

SHLGE08283L38L42

323

SHL-UBA-08

82

Shell

Geosurce

24025

1513

3915.4

mig

69.956 CP25961_03_SHL-UBA-08.sgy

SHLGE08283L38L42

324

SHL-UBA-09

82

Shell

Geosurce

10241

2210.5

3234.5

mig

29.044 CP25960_02_SHL-UBA-09.sgy

SHLGE08283L38L42

325

SHL-UBA-10

82

Shell

Geosurce

11761

1767

2943

mig

33.737 CP25960_03_SHL-UBA-10.sgy

SHLGE08283L38L42

326

SHL-UBA-11

82

Shell

Geosurce

13481

1641

2989

mig

38.569 CP25960_04_SHL-UBA-11.sgy

SHLGE08283L38L42

327

SHL-UBA-12

82

Shell

Geosurce

7586

2552.5

3311

mig

21.042 CP25960_05_SHL-UBA-12.sgy

SHLGE08283L38L42

328

SHL-UBA-13

83

Shell

Geosurce

35296

437

3967

mig

Pagoreni_

102.541 CP25960_06_SHL-UBA-13.sgy

SHLGE08283L38L42

329

SHL-UBA-13NW

83

Shell

Geosurce

10041

2965

3969

mig

Cashiriari_

330

SHL-UBA-14

83

Shell

Geosurce

12681.5

1773.5

3041.5

mig

Sepa_1X

Km

Survey name by PERUPETRO (Navigation too)

Line-Name by PARSEP

Page 9

Well

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

No

28.646 EP20340_16_SHL-UBA-13NW.sgy

SHLGE08283L38L42

35.785 CP25185_02_SHL-UBA-14.sgy

SHLGE08283L38L42

331

SHL-UBA-16

83

Shell

Geosurce

6401

1021.5

1661.5

mig

18.336 CP25960_07_SHL-UBA-16.sgy

SHLGE08283L38L42

332

SHL-UBA-17

83

Shell

Geosurce

5441

2652

3196

mig

15.437 CP25960_08_SHL-UBA-17.sgy

SHLGE08283L38L42

333

SHL-UBA-19

83

Shell

Geosurce

5773

984

1561.2

mig

Mipaya_1X

16.518 CP25960_09_SHL-UBA-19.sgy

SHLGE08283L38L42

334

SHL-UBA-22_39

83

Shell

Geosurce

8324

1003.5

1835.8

mig

San-Martín

23.277 EP20340_03_SHL-UBA-22_39.sgy

SHLGE08283L38L42

335

SHL-UBA-23_37 TOT39-10 TOT39-101A TOT39-101B TOT39-101C TOT39-103 TOT39-104 TOT39-106 TOT39-106E TOT39-108 TOT39-110 TOT39-112 TOT39-12 TOT39-1N TOT39-1S TOT39-201 TOT39-203 TOT39-205 TOT39-207 TOT39-209 TOT39-214 TOT39-216 TOT39-218 TOT39-220 TOT39-2W TOT39-2W_E TOT39-3 TOT39-302 TOT39-303 TOT39-305 TOT39-307 TOT39-4 TOT39-5A TOT39-5B TOT39-6A TOT39-6B TOT39-8

EP20340_02_SHL-UBA-23_37.sgy EP20179_06_TOT-39-10.sgyqc EP20177_16_TOT-39-101.sgyqc EP20177_15_TOT-39-101.sgyqc EP20177_14_TOT-39-101.sgyqc EP20179_07_TOT-39-103.sgyqc EP20177_02_TOT-39-104.sgyqc EP20177_03_TOT-39-106.sgyqc EP20177_04_TOT-39-106E.sgyqc EP20177_17_TOT-39-108.sgyqc EP20179_08_TOT-39-110.sgyqc EP20179_09_TOT-39-112.sgyq EP20177_18_TOT-39-12.sgyqc EP20177_05_TOT-39-1N.sgyqc EP20179_01_TOT-39-1S.sgyqc EP20177_19_TOT-39-201.sgyqc EP20179_10_TOT-39-203.sgyqc EP20177_20_TOT-39-205.sgyqc EP20179_11_TOT-39-207.sgyqc EP20179_12_TOT-39-209.sgyqc EP20177_21_TOT-39-214.sgyqc EP20179_13_TOT-39-216.sgyqc EP20179_14_TOT-39-218.sgyqc EP20179_15_TOT-39-220.sgyqc EP20177_07_TOT-39-2W.sgyqc EP20179_02_TOT-39-2W_E.sgyqc EP20179_03_TOT-39-3.sgyqc EP20179_16_TOT-39-302.sgyqc EP20177_22_TOT-39-303.sgyqc EP20177_23_TOT-39-305.sgyqc EP20179_17_TOT-39-307.sgyqc EP20179_04_TOT-39-4.sgyqc EP20177_09_TOT-39-5.sgyqc EP20177_10_TOT-39-5.sgyqc EP20177_12_TOT-39-6.sgyqc EP20177_11_TOT-39-6.sgyqc EP20179_05_TOT-39-8.sgyqc

SHLGE08283L38L42 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39 TOTCGG7375L39

337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371

Shot for

Shot by

No Trace

Sp_a

Sp_z

segy

83

Shell

Geosurce

10169

1028.5

2045.3

mig

73-75

Total

Compañía Gene

1825

13

925

mig

73-75

Total

Compañía Gene

700

526

176.5

mig

73-75

Total

Compañía Gene

817

714

306

mig

73-75

Total

Compañía Gene

505

954

702

mig

73-75

Total

Compañía Gene

1234

60

676.5

mig

73-75

Total

Compañía Gene

1339

82

751

mig

73-75

Total

Compañía Gene

874

858

421.5

mig

73-75

Total

Compañía Gene

886

1466

1908.5

mig

73-75

Total

Compañía Gene

1180

68

657.5

mig

73-75

Total

Compañía Gene

1705

88

940

mig

73-75

Total

Compañía Gene

1663

81

912

mig

73-75

Total

Compañía Gene

1681

98

938

mig

73-75

Total

Compañía Gene

693

452

106

mig

73-75

Total

Compañía Gene

1314

1066.5

410.5

mig

73-75

Total

Compañía Gene

826

82

494.5

mig

73-75

Total

Compañía Gene

1351

23

698

mig

73-75

Total

Compañía Gene

547

335

608

mig

73-75

Total

Compañía Gene

547

71

344

mig

73-75

Total

Compañía Gene

1009

57

561

mig

73-75

Total

Compañía Gene

832

117

532.5

mig

73-75

Total

Compañía Gene

1354

74

750.5

mig

73-75

Total

Compañía Gene

1441

72

792

mig

73-75

Total

Compañía Gene

1582

111

901.5

mig

73-75

Total

Compañía Gene

349

101

275

mig

73-75

Total

Compañía Gene

1361

266

946

mig

73-75

Total

Compañía Gene

897

31

479

mig

73-75

Total

Compañía Gene

571

186

471

mig

73-75

Total

Compañía Gene

673

Total

Compañía Gene

886

73-75

Total

Compañía Gene

781

149 146 251

485 590 641

mig

73-75 73-75

Total

Compañía Gene

1639

92

911

mig

73-75

Total

Compañía Gene

1009

102

606

mig

73-75

Total

Compañía Gene

733

585

951

mig

73-75

Total

Compañía Gene

885

101

543

mig

73-75

Total

Compañía Gene

823

528

939

mig

73-75

Total

Compañía Gene

1813

72

978

mig

mig mig

Page 10

Well

Panguana

Km

Survey name by PERUPETRO (Navigation too)

Line-Name by PARSEP

336

Year

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

No

28.181 110.919 38.851 52.429 32.545 75.884 84.542 50.079 54.971 71.731 106.785 103.599 104.513 37.941 72.711 51.339 84.045 33.769 33.808 59.735 52.134 83.266 87.742 99.041 20.222 86.573 54.817 27.755 42.323 43.166 48.371 101.036 63.565 47.731 51.599 49.694 101.900

No

Line-Name by PARSEP

Year

372

W73-28STK W73-70MIG W74-20MIG W74-23STK W74-24STK W74-25STK W74-26STK W74-27MIG W74-29STK3 W74-31MIG W74-32STK W74-33MIG W74-34MIG W74-35STK W74-36STK W74-44STK W74-49MIG W74-51STK W74-52STK2 W74-53STK W74-55MIG W74-56STK W74-66MIG W74-68MIG W74-69MIG W74-73STK W74-75STK W75-100MIG W75-101MIG W75-102MIG W75-103MIG W75-30MIG W75-67MIG W75-71STK W75-74STK W75-76ASTK W75-77MIG W75-78ASTK W75-79MIG W75-84STK W75-85MIG W75-86AMIG W75-86MIG W75-87MIG W75-88STK W75-89MIG

73-75

Signal

Western Geophy

541

273

73-75

Signal

Western Geophy

691

350

73-75

Signal

Western Geophy

226

73-75

Signal

Western Geophy

394

73-75

Signal

Western Geophy

312

157.5

2.5

stk

73-75

Signal

Western Geophy

313

16

172

stk

73-75

Signal

Western Geophy

451

374

149

stk

73-75

Signal

Western Geophy

693

498

153

mig

73-75

Signal

Western Geophy

895

2

449

stk

73-75

Signal

Western Geophy

829

3

417

mig

73-75

Signal

Western Geophy

913

12

468

stk

73-75

Signal

Western Geophy

937

-99

369

mig

73-75

Signal

Western Geophy

514

2

258.5

mig

73-75

Signal

Western Geophy

634

2

318.5

stk

73-75

Signal

Western Geophy

1267

803

170

stk

73-75

Signal

Western Geophy

463

271

40

stk

73-75

Signal

Western Geophy

316

5

162.5

mig

73-75

Signal

Western Geophy

358

2

180.5

stk

73-75

Signal

Western Geophy

361

9

189

stk

73-75

Signal

Western Geophy

775

20

407

stk

73-75

Signal

Western Geophy

637

2

320

mig

73-75

Signal

Western Geophy

448

2

225.5

stk

73-75

Signal

Western Geophy

611

308

3.5

mig

73-75

Signal

Western Geophy

193

37

133

mig

73-75

Signal

Western Geophy

559

2

281

mig

73-75

Signal

Western Geophy

211

107

2

stk

73-75

Signal

Western Geophy

515

275

18

stk

73-75

Signal

Western Geophy

331

179

14

mig

73-75

Signal

Western Geophy

119

110

51

mig

73-75

Signal

Western Geophy

135

258

191

mig

73-75

Signal

Western Geophy

475

331

94

mig

73-75

Signal

Western Geophy

575

3

290

mig

73-75

Signal

Western Geophy

253

5

131

mig

73-75

Signal

Western Geophy

675

339

2

stk

73-75

Signal

Western Geophy

243

20

141

stk

73-75

Signal

Western Geophy

235

2

119

stk

73-75

Signal

Western Geophy

419

215

6

mig

73-75

Signal

Western Geophy

371

215

30

stk

73-75

Signal

Western Geophy

555

296

19

mig

73-75

Signal

Western Geophy

143

73

2

stk

73-75

Signal

Western Geophy

191

97

2

mig

73-75

Signal

Western Geophy

243

221

100

mig

73-75

Signal

Western Geophy

191

97

2

mig

73-75

Signal

Western Geophy

455

205

432

mig

73-75

Signal

Western Geophy

304

339.5

188.5

stk

73-75

Signal

Western Geophy

475

268

31

mig

373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417

Shot for

Shot by

No Trace

Sp_a

Sp_z

segy

Well

3

stk

Tamaya_1

5

mig

6

118.5

mig

198.5

2

stk

Page 11

Río-Caco_

Km

34.051 43.844 14.332 24.823 19.916 19.435 28.800 44.238 57.788 53.301 59.346 59.902 32.509 40.639 82.234 30.044 19.526 22.236 23.423 49.719 40.073 28.529 38.987 11.731 34.865 13.146 32.661 20.661 6.516 7.655 29.186 36.886 15.688 43.737 15.927 14.392 25.998 23.294 35.217 9.142 11.850 15.615 11.640 31.309 19.089 29.760

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

w74(73)-28stk w75(73)-70mig w74-20mig w74-23stk w74-24stk w74-25stk w74-26stk w74-27mig w74-29stk3 w74-31mig w74-32stk w74-33mig w74-34mig w74-35stk w74-36stk w74-44stk w74-49mig w74-51stk w74-52stk2 w74-53stk w74-55mig w74-56stk w74-66mig w74-68mig w74-69mig w74-73stk w74-75stk w75-100mig w75-101mig w75-102mig w75-103mig w74(75)-30mig w75-67mig w75-71stk w75-74stk w75-76Amig w75-77mig w75-78Astk w75-79mig w75-84stk w74(75)-85mig w75-86Amig w75-86mig w75-87mig w75-88stk w74(75)-89mig

Survey name by PERUPETRO (Navigation too)

SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33

No

Line-Name by PARSEP

418

W75-91MIG 73-75 Signal W75-92MIG 73-75 Signal W75-93STK 73-75 Signal W75-94ASTK 73-75 Signal W75-95MIG 73-75 Signal W75-96MIG 73-75 Signal

Page 12

Well

Km

SEG-Y PERUPETRO Code (only one class was used by PARSEP)

42.836 w75-91mig 18.309 w75-92mig 11.540 w75-93stk 12.885 w75-94Astk 41.655 w75-95mig 34.550 w75-96mig 13736.646 km

Survey name by PERUPETRO (Navigation too)

SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33 SIGWG7375L33