Reassessment of the Bahamas Fracture Zone

Conference · Thu Feb 28 23:00:00 EST 1991 · AAPG Bulletin (American Association of Petroleum Geologists); (United States)

OSTI ID:5862899

Ball, M M ^[1]

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1. Geological Survey, Evergreen, CO (United States)

The Bahamas Fracture Zone trends northwestward across south Florida and the Western Florida shelf, and it appears to connect with the Gilbertown-Pickens-Pollard portion of the circum-Gulf of Mexico fault system. Along the fracture zone's trend, seismic reflection data reveal normal displacement in the Late Jurassic section of a kilometer, on a down-to-the-west fault, 9 km east of the east end of Destin dome in the Apalachicola basin. This fault was active in Late Jurassic and Early Cretaceous time during the gulf spreading event. The Middle Jurassic Louann Salt thins abruptly to the east across this fault. Toward the southeast, where the fracture zone crosses the Florida peninsula, gravity data have previously been interpreted to indicate coincidence of the Bahamas Fracture Zone with a hinge zone attended by relief on the Mohorovicic discontinuity. This interpretation is an artifact resulting from the use of erroneously low densities for the sedimentary fill of the South Florida basin. The inclusion of a nonexistent negative component for the basin's sedimentary fill necessitated the inclusion of an equally nonexistent positive contribution from relief on the Moho in order to match the observed anomaly. Although northwestward-trending faults do cross south Florida and the Western Florida shelf, the role of the Bahamas Fracture Zone as a boundary between continental and transitional or oceanic crust is insupportable.

• OSTI ID: 5862899
• Report Number(s): CONF-910403--
• Journal Information: AAPG Bulletin (American Association of Petroleum Geologists); (United States), Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (United States) Vol. 75:3; ISSN AABUD; ISSN 0149-1423
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
CONTINENTAL CRUST
CONTINENTAL MARGIN
CONTINENTAL SHELF
CRETACEOUS PERIOD
DEVELOPED COUNTRIES
EARTH CRUST
FEDERAL REGION IV
FLORIDA
GEOLOGIC AGES
GEOLOGIC FAULTS
GEOLOGIC FRACTURES
GEOLOGIC HISTORY
GEOLOGIC STRUCTURES
GEOPHYSICAL SURVEYS
GRAVITY SURVEYS
JURASSIC PERIOD
MAPPING
MESOZOIC ERA
NORTH AMERICA
OCEANIC CRUST
SEA-FLOOR SPREADING
SEISMIC SURVEYS
SURVEYS
USA