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John Kingston1 Open-File Report 94-559 This Report Is Preliminary and Has Not Been Reviewed for Conformity with U.S. Geological

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John Kingston1 Open-File Report 94-559 This Report Is Preliminary and Has Not Been Reviewed for Conformity with U.S. Geological U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY UNDISCOVERED PETROLEUM OF SOUTHERN SOUTH AMERICA by John Kingston1 Open-File Report 94-559 This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards and stratigraphic nomenclature. 1 Palo Alto f CA (retired) Table of Contents Undiscovered Petroleum of Southern South America Page List of Figures ..............................................iii List of Tables ............................................xvii Abstract ............................................... 1 I. Introduction ............................................... 1 A. Regions of Study ...................................... 1 B. Purpose and Method of Study ........................... 1 II. Brazilian Craton Region ................................... 4 A. The Rifted Continental Margin Basins .................. 7 1. General .......................................... 7 2. Individual Basin Assessment ...................... 16 a. Southern Rifted Continental Margins .......... 16 1) Campos ................................... 16 2) Santos ................................... 53 3) Pelotas .................................. 59 4) Espirito Santo............................ 63 5) Bahia Sul................................. 74 6) Sergipe-Alagoas........................... 79 b. Northeastern Rifted and Wrenched Margin ...... 89 1) Potiguar.................................. 92 2) Caera.................................... 101 3) Barreirinhas............................. 109 4) Para-Maranhoa............................ 117 5) Foz do Amazonas.......................... 123 6) Guyana................................... 132 B. Brazilian Interior Rift Basins ...................... 138 1. Recancavo ....................................... 138 2. Tucano and Jatoba ............................... 144 3. Tacutu .......................................... 152 C. Brazilian Interior Sag Basins ....................... 157 1. Solimoes ........................................ 158 2. Amazonas ........................................ 168 3. Parnaiba ........................................ 175 4. Parana .......................................... 186 5. Chaco ........................................... 194 D. Subandian Foreland ................................. 194 1. Acre ............................................ 194 III. Patagonian Accreted Region ............................. 201 A. Foreland/Interior Rift Basins ....................... 201 1. Magallanes ..................................... 203 2. Malvinas ........................................ 212 3. Malvinas Plateau ................................ 218 4. Malvinas Trough ................................. 221 5. San Jorge ....................................... 223 6. Colorado ........................................ 234 7. Salado .......................................... 239 8. Nirihuah ........................................ 244 9. Neuquen ......................................... 244 10. Cuyo.............................................253 B. Rifted Continental Margin Basin ..................... 260 1. East Patagonia .................................. 260 IV. Subandian Basins ........................................ 267 A. Foreland Basins ..................................... 269 1. Pampeanas ...................................... 270 2. Oran ............................................ 274 3. Santa Cruz-Tarija ............................... 284 4. Beni ............................................ 294 5. Madre de Dios ................................... 300 6. Ucayali ......................................... 304 7. Maranon-Oriente-Putumayo ........................ 314 B. Overthrust and Fold Belt Basins ..................... 329 1. Huallaga ........................................ 329 2. Santiago ........................................ 336 C. Andean Intra-Arc Basin .............................. 338 1. Altiplano ....................................... 339 D. Pacific Coastal Forearc and Intra-arc Basins ........ 344 1. Puruvian and Ecuadorian Coastal Basins ..........344 a. Forearc Basins .............................. 345 1) Talara...................................348 2) Progreso................................. 355 3) Esmeraldas-Caraguez...................... 363 4) Trujillo................................. 366 5) Lima..................................... 371 6) Mellenda-Tarapaca........................ 371 b. Intra-arc Basins ............................ 374 1) Lancones................................. 374 2) Manibi...................................376 3) Borbon...................................378 4) Sechura.................................. 380 5) Salaverry................................ 383 6) Pisco.................................... 386 7) Moquegua-Tamaruga........................ 390 8) Salar de Atacama (Antofagasta)........... 392 2. South Chilean Coastal Basins .................... 393 a. Forearc Basins .............................. 393 1) Central Chilean ......................... 395 2) Madre de Dios............................ 403 3) Diego Ramirez............................ 406 b. Coastal Intra-arc Basins .................... 409 1) Osorno-Llanguehue........................ 409 2) Temuco................................... 411 3) Carico...................................412 4) Penas.................................... 413 V. Summary and Conclusions .................................. 415 Bibliography ............................................. 428 Appendix A ............................................. 438 11 List of Figures Page 1. Map showing the five principal geotectonic regions of South America. ................................. 3 2. Map showing principal sedimentary basins of the Brazilian Shield area. .................................... 5 3. Map of the Brazilian Atlantic margin. ..................... 9 4. Structure map on top of acoustic basement in the Campos basin. ............................................ 10 5. Section showing tecto-sedimentary evolution of the Brazilian continental margin in the Campos basin. ........ 12 6. Geologic strike section through the Brazilian rifted continental marginal basins. ...................... 14 7. Index map of the Campos basin. ........................... 18 8. Stratigraphic column of Campos basin shelf. .............. 19 9. Geochemical profiles of various parameters as observed in through the oil-generating zone of Wildcat R-JS-76 of central Campos basin. ................. 21 10. Subsidence rates along the Brazilian continental margin. .................................................. 23 11. Campos basin oil fields and production systems, 1988. .................................................... 26 12. Graph showing the relation of the quantity of discovered oil and gas against the number of wildcat drilled in the Campos basin. ..................... 28 13. Structural-stratigraphic section through the Badejo high of the Campos basin. ......................... 31 14. Dip seismic section through the Campos basin. ............ 34 15. Isopach maps of Cretaceous combined sandstone thicknesses, in meters, on the Campos basin shelf. ....... 35 16. Stratigraphic column of the Tertiary section of the Albacora Field of the Campos basin. .................. 37 17. Paleogeography of the Oligocene turbidite system in Campos basin. ......................................... 38 111 18. Location map of the Albacora and Marlim fields and 3-D surveys in deep water (modified from Souza et al, 1989). ............................................ 40 19. A 3-D seismic dip section across the Albacora Field and its interpretation. .................................. 41 20. Seismic profiles (A and B) across the Marlin and Barracuda complex of fields. ............................ 42 21. A 3-D seismic strike section through the Marlim field showing its interpretation and the anomalously high reflection amplitude at the top interface of an oil-filled Eocene turbidite. ............................. 43 22. Maps of the Marlim-Barracuda field complexes showing how clearly the fields, particularly the Marlim complex, are outlined by high amplitude effects at the top of the main Oligocene turbidites. ..... 44 23. Map showing prospective deep-water areas of the Campos basin being considered for future drilling. ....... 46 24. Seismic section A-A' indicating eastward extension of reservoirs (cross-hatched) of Campos basin identified in wildcat l-RJS-366 and independent structure to southeast. .................................. 47 25. Seismic section B-B' in the Albacora area showing reservoirs (cross-hatched) of Campos basin and emphasizing synrift targets. ............................. 48 26. Seismic section C-C' in wildcat l-RJS-490 area of Campos basin showing interpreted reservoirs (cross-hatched) including possible (OLIG) Oligocene lowstand fan system. ........................... 49 27. Seismic section D-D at extreme south of Campos basin showing complex structure and in particular faults which cut Miocene reservoir horizons (cross-hatched) and may serve as conduits for oil migration. ........................................... 50 28. Index map of the Santos basin showing position of gas and oil fields, geologic sections and wildcats. ...... 54 29. Stratigraphic chart of Santos basin. ..................... 55 30. Geologic section in southern portion of Santos basin. ................................................... 56 31. Geologic section of central portion of Santos basin. ....
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