Crustal structure and tectonic development of Gulf of Guinea Cul-deSac from integrated interpretation of new aeromagnetic and existing geophysical data

Conference · Fri Feb 01 00:00:00 EST 1985 · Am. Assoc. Pet. Geol., Bull.; (United States)

OSTI ID:5921910

Babalola, O O

Data-acquisition difficulties and propriety restrictions on industry data have necessitated liberal extrapolations and generalizations in previous tectono-structural studies of the Gulf of Guinea cul-de-sac. This region is the locus of a postulated Late Cretaceous triple junction whose arms were the transform-dominated Equatorial Atlantic, the northward-propagating South Atlantic, and the Benue Trough aulacogen. Oceanic crust has been inferred to underlie most of the thick sedimentary wedge of the oil-prolific Niger Delta basin. Integrated interpretation of new aeromagnetic data of the Geological Survey of Nigeria and existing geophysical data corroborates previous work on the general structure of the marginal basins. New aeromagnetic data, however, reveal a detail structure more complex than previously known. Low-frequency magnetic anomalies over the Niger delta indicate that oceanic crust extends northward to about Onitsha. From Onitsha, the edge of oceanic crust extends northward to about Onitsha. From Onitsha, the edge of oceanic crust trends southwestward along the Benin hinge line (an apparent continental continuation of either the Chain fracture zone or a new Okitipupa fracture zone) and also wiggles southeastward (adjoined by a wide margin of transitional crust) toward the shelf break off Cameroon. Linear magnetic anomalies trending northeast indicate about 7 fracture zones beneath the Niger Delta basin. The region of high-frequency magnetic anomalies west of the Niger delta represent the Okitipupa basement ridge complex, which separates the Niger Delta basin from the Dahomey embayment. In this embayment, 2 wide bands of intervening high- and low-frequency aeromagnetic anomalies are interpreted to represent a basement high or ridge and a fault-bonded trough, respectively.

• Research Organization: Univ. of Texas, Austin
• OSTI ID: 5921910
• Report Number(s): CONF-850322-
• Journal Information: Am. Assoc. Pet. Geol., Bull.; (United States), Vol. 69:2; Conference: American Association of Petroleum Geologists annual meeting, New Orleans, LA, USA, 25 Mar 1985
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
NIGERIA
GEOLOGIC HISTORY
TECTONICS
ATLANTIC OCEAN
CRETACEOUS PERIOD
GEOLOGIC FAULTS
GEOPHYSICAL SURVEYS
NIGER RIVER
AFRICA
DEVELOPING COUNTRIES
GEOLOGIC AGES
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
MESOZOIC ERA
RIVERS
SEAS
STREAMS
SURFACE WATERS
SURVEYS
020200* - Petroleum- Reserves
Geology
& Exploration