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Title: Oil exploration in nonmarine rift basins of interior Sudan

In early 1975 Chevron Overseas Petroleum Inc. commenced a major petroleum exploration effort in previously unexplored interior Sudan. With the complete cooperation of the Sudanese Government, Chevron has acquired a vast amount of geologic and geophysical data during the past 9 years. These data include extensive aeromagnetic and gravity surveys, 25,000 mi (40,200 km) of seismic data, and the results of 66 wells. This information has defined several large rift basins which are now recognized as a major part of the Central African rift system. The sedimentary basins of interior Sudan are characterized by thick Cretaceous and Tertiary nonmarine clastic sequences. Over 35,000 ft (10,600 m) of sediment have been deposited in the deepest trough, and extensive basinal areas are underlain by more than 20,000 ft (6100 m) of sediment. The depositional sequence includes thick lacustrine shales and claystones, flood plain claystones, and lacustrine, fluvial, and alluvial sandstones and conglomerates. Those lacustrine claystones which were deposited in an anoxic environment provide oil-prone source rocks. Reservoir sandstones have been found in a wide variety of nonmarine sandstone facies. The extensional tectonism which formed these basins began in the Early Cretaceous. Movement along major fault trends continued intermittently into the Miocene. Thismore » deformation resulted in a complex structural history which led to the formation of several deep fault-bounded troughs, major interbasin high trends, and complex basin flanks. This tectonism has created a wide variety of structures, many of which have become effective hydrocarbon traps.« less
Authors:
Publication Date:
OSTI Identifier:
6185385
Report Number(s):
CONF-8405216-
Journal ID: CODEN: AAPGB
Resource Type:
Conference
Resource Relation:
Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States); Journal Volume: 68:4; Conference: AAPG annual convention, San Antonio, TX, USA, 20 May 1984
Research Org:
Chevron USA Inc., Concord, CA
Country of Publication:
United States
Language:
English
Subject:
02 PETROLEUM; PETROLEUM DEPOSITS; EXPLORATION; SUDAN; CRETACEOUS PERIOD; PETROLEUM GEOLOGY; RESERVOIR ROCK; SOURCE ROCKS; TECTONICS; TERTIARY PERIOD; AFRICA; CENOZOIC ERA; DEVELOPING COUNTRIES; GEOLOGIC AGES; GEOLOGIC DEPOSITS; GEOLOGY; MESOZOIC ERA; MINERAL RESOURCES; RESOURCES 020200* -- Petroleum-- Reserves, Geology, & Exploration