Source rocks of the Sub-Andean basins

Conference · Mon Feb 01 04:00:00 EST 1993 · AAPG Bulletin (American Association of Petroleum Geologists); (United States)

OSTI ID:6066994

Raedeke, L D ^[1]

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1. Chevron Overseas Petroleum Inc., San Ramon, CA (United States)

Seven source rock systems were mapped using a consistent methodology to allow basin comparison from Trinidad to southern Chile. Silurian and Devonian systems, deposited in passive margin and intracratonic settings, have fair-good original oil/gas potential from central and northern Bolivia to southern Peru. Kerogens range from mature in the foreland to overmature in the thrust belt. Permian to Carboniferous deposition in local restricted basins formed organic-rich shales and carbonates with very good original oil/gas potential, principally in northern Bolivia and southern Peru. Late Triassic to early Jurassic marine shales and limestones, deposited in deep, narrow, basins from Ecuador to north-central maturity. Locally, in the Cuyo rift basin of northern Argentina, a Triassic lacustrine unit is a very good, mature oil source. Early Cretaceous to Jurassic marine incursions into the back-arc basins of Chile-Argentina deposited shales and limestones. Although time transgressive (younging to the south), this system is the principal source in southern back-arc basins, with best potential in Neuquen, where three intervals are stacked A late Cretaceous marine transgressive shale is the most important source in northern South America. The unit includes the La Luna and equivalents extending from Trinidad through Venezuela, Colombia, Ecuador, and into northern Peru. Elsewhere in South America upper Cretaceous marine-lacustrine rocks are a possible source in the Altiplano and Northwest basins of Bolivia and Argentina. Middle Miocene to Oligocene source system includes shallow marine, deltaic, and lacustrine sediments from Trinidad to northern Peru.

• OSTI ID: 6066994
• Report Number(s): CONF-930306--
• Conference Information: Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (United States) Journal Volume: 77:2
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
ARGENTINA
BOLIVIA
CARBON COMPOUNDS
CARBONATES
CHILE
COLOMBIA
COMPARATIVE EVALUATIONS
CRETACEOUS PERIOD
DEVELOPING COUNTRIES
ECUADOR
EVALUATION
GEOLOGIC AGES
GEOLOGIC STRUCTURES
GEOLOGY
JURASSIC PERIOD
LATIN AMERICA
MAPPING
MESOZOIC ERA
OXYGEN COMPOUNDS
PERU
PETROLEUM GEOLOGY
ROCKS
SEDIMENTARY BASINS
SEDIMENTARY ROCKS
SEDIMENTS
SHALES
SOURCE ROCKS
SOUTH AMERICA
TRIASSIC PERIOD
VENEZUELA