Geology and petroleum resources of Venezuela
Venezuela occupies a peripheral position to the Guiana shield and craton in northern South America. The larger sedimentary basins of the Venezuelan craton zone are marginal cratonic basins (Lanos-Barinas), resulting from Tertiary Andean eastward movements, and basins formed by collisional, extensional, and transformed movement of the American portion of Tethys (eastern Venezuela-Trinidad). The smaller sedimentary basins of Venezuela are Tertiary transverse-wrench basins in the disturbed intermontane zone peripheral to the cratonic basins (Maracaibo, Falcon, parts of the Gulf of Venezuela, Carioca, and parts of Tobago-Margarita). Venezuela accounts for 75% of the recoverable oil and 55% of the gas discovered in South America. These deposits occur primarily in two basins (East Venezuela and Maracaibo - where one complex, the Bolivar Coastal and lake pools, represents 40% of South American discovered oil). The East Venezuela basin contains the Orinico heavy oil belt, currently assessed at 1 to 2 trillion bbl of oil in place. Source rocks for Venezuelan hydrocarbons are middle Cretaceous calcareous bituminous shales and marls (40% of discovered hydrocarbons), lower Tertiary deltaic and transitional shales, Paleocene-Eocene (40%), and Oligocene-Miocene deltaic and coastal shales (20%). A key factor in high recovery of hydrocarbons appears to be preservation of middle Cretaceous and lower Tertiary source rocks during maturation and migration. Reservoirs are dominantly (> 90%) clastic sediments (sandstones) within, above, or updip from source sequences. Cap rocks are interbedded and overlying shale.
- Research Organization:
- Geo Basins, Ltd., Bondville, VT
- OSTI ID:
- 5166879
- Report Number(s):
- CONF-860624-
- Journal Information:
- Am. Assoc. Pet. Geol., Bull.; (United States), Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States) Vol. 70:5; ISSN AAPGB
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
020200* -- Petroleum-- Reserves
Geology
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03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
BITUMINOUS MATERIALS
CARBONACEOUS MATERIALS
CENOZOIC ERA
DEVELOPING COUNTRIES
ENERGY SOURCES
FOSSIL FUELS
FUELS
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC STRUCTURES
GEOLOGY
LATIN AMERICA
MATERIALS
MINERAL RESOURCES
NATURAL GAS DEPOSITS
OIL SANDS
PETROLEUM DEPOSITS
PETROLEUM GEOLOGY
RESERVES
RESERVOIR ROCK
RESOURCE POTENTIAL
RESOURCES
ROCKS
SANDSTONES
SEDIMENTARY BASINS
SEDIMENTARY ROCKS
SHALES
SOURCE ROCKS
SOUTH AMERICA
TERTIARY PERIOD
VENEZUELA