Geophysics and structure of Carolina Trough, Blake Plateau, and Bahama Platform
South of Cape Hatteras, the linear fault-bounded Carolina Trough is marked on its landward side by a prominent hinge zone in basement under the Brunswick magnetic anomaly, and on its seaward side by the East Coast magnetic anomaly (ECMA). In between the two anomalies, a transitional basement at depths of 12-14 km is overlain by Jurassic and younger post-rift strata. Jurassic salt is evidenced as numerous diapirs along the base of the continental slope under the ECMA. Large scale growth faults along the shelf edge dip eastward from near the sea-floor to the salt layer. East of Florida, underlying the Blake Plateau is a sedimentary basin on transitional basement at 12-14 km depths. Middle Jurassic to Lower Cretaceous sediments are shallow water limestones, dolomites, and evaporites. After Middle Cretaceous time, continued subsidence of the Plateau, along with sediment starvation related to the Florida Current evolution, led to deep-water, calcareous ooze deposition in bathyal depths. The western Bahama Platform in underlain by rifted, transitional basement which is buried by Upper Jurassic and younger carbonate and evaporite rocks. Oceanic crust is thought to underlay the southeastern Bahama Platform seaward of the extensions of BSMA. A carbonate mega-platform spread from the Bahamas along the entire Atlantic margin in Late Jurassic to Early Cretaceous time. After a major drowning event in Middle Cretaceous time, only the isolated Bahama Banks maintained themselves at sea-level and remain surrounded by deep-water channels that have evolved since then.
- Research Organization:
- Univ. of Delaware, Newark (USA)
- OSTI ID:
- 6274097
- Report Number(s):
- CONF-8510489-
- Journal Information:
- Geol. Soc. Am., Abstr. Programs; (United States), Journal Name: Geol. Soc. Am., Abstr. Programs; (United States) Vol. 17; ISSN GAAPB
- Country of Publication:
- United States
- Language:
- English
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Tectonic structure and evolution of the Atlantic continental margin
Reassessment of the Bahamas Fracture Zone
Related Subjects
580100* -- Geology & Hydrology-- (-1989)
ATLANTIC OCEAN
BAHAMA ISLANDS
CONTINENTAL MARGIN
CRETACEOUS PERIOD
DEVELOPING COUNTRIES
EARTH CRUST
FEDERAL REGION IV
FLORIDA
GEOLOGIC AGES
GEOLOGIC FAULTS
GEOLOGIC FRACTURES
GEOLOGIC HISTORY
GEOLOGIC STRUCTURES
GEOLOGY
GEOPHYSICAL SURVEYS
GEOPHYSICS
ISLANDS
JURASSIC PERIOD
MAGNETISM
MESOZOIC ERA
NORTH AMERICA
NORTH CAROLINA
OCEANIC CRUST
PALEOMAGNETISM
RIFT ZONES
SEAS
SURFACE WATERS
SURVEYS
USA
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