Early Cretaceous platform re-entrant and escarpment erosion in the Bahamas
Early Cretaceous platform re-entrant and escarpment erosion in the Bahamas
Geology (Boulder) (March 1984) 12 (3): 147-150
- Atlantic Ocean
- Bahamas
- Blake Plateau
- bottom features
- carbonate rocks
- Caribbean region
- Cretaceous
- Deep Sea Drilling Project
- deep-sea sedimentation
- depth indicators
- dredged samples
- DSDP Site 99
- environmental analysis
- faults
- geophysical methods
- geophysical surveys
- Leg 11
- Lower Cretaceous
- marine sedimentation
- Mesozoic
- multichannel filters
- North American Atlantic
- North Atlantic
- ocean floors
- oceanography
- paleogeography
- processes
- reflection methods
- scarps
- sedimentary rocks
- sedimentation
- seismic methods
- submarine canyons
- surveys
- West Indies
- Bahama Escarpment
- Exuma Canyon
A multichannel, 24-fold seismic profile crossing the Bahama Escarpment south of San Salvador is tied stratigraphically to Deep Sea Drilling Project Site 99 and dredge hauls on the eroded platform slopes in the Bahamas. Conclusions: (1) a deep-water sequence crops out in Exuma Canyon west of the Bahama Escarpment between 2,6000 and 3,800 m and includes Valanginian through Cenomanian chalk and limestone presumably deposited in a re-entrant between the platforms; (2) beneath these carbonates the seismic data indicate a possible reef structure at 5,700 m and prograding clinoforms suggestive of rapidly deposited rift(?) sediments below 6,500 m; (3) the Bahama Escarpment, like the Blake Escarpment, is an erosional slope exposing Jurassic(?) to Early Cretaceous back-reef limestones; geometry indicates an erosional retreat of ca. 5 km of the base of the escarpment since Early Cretaceous time; (4) major faults may separate the re-entrant sequence from the ridge forming the escarpment and may also define Exuma Canyon and the escarpment itself.--Modified journal abstract.