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Subsidence, crustal structure, and thermal evolution of Georges Bank basin

January 1, 1987

A geophysical study of Georges Bank basin defines a deep crustal structure that is interpreted in terms of the basin's tectonic and thermal history. Gravity models along three basin cross sections delineate two zones of crustal thinning at the basement hinge zone and oceanic crustal margins. These two zones bound rift-stage crust (about 25 km thick) which underlies the central portion of the basin. Subsidence analysis of the basin, using data from multichannel seismic reflection lines and two COST wells, suggests a rifting and (uniform) extensional origin. Two-dimensional finite difference modeling of the basin defines a crustal structure that concurs with the gravity and subsidence studies. The resulting isotherms show no major changes in the thermal structure since the ate Jurassic. In some areas of the basin, temperatures sufficient for oil generation are determined from maturation studies of Jurassic sediments. Hydrocarbon generation is questionable, however, because of the probable lack of proper and sufficient kerogen in the Jurassic deposits.

Publication Year 1987
Title Subsidence, crustal structure, and thermal evolution of Georges Bank basin
DOI 10.1306/94887893-1704-11D7-8645000102C1865D
Authors B. Ann Swift, D. S. Sawyer, J. A. Grow, Kim D. Klitgord
Publication Type Article
Publication Subtype Journal Article
Series Title American Association of Petroleum Geologists Bulletin
Index ID 70015218
Record Source USGS Publications Warehouse
USGS Organization Woods Hole Coastal and Marine Science Center