Depositional environments of and evidence for the erosional origin of the Blake Escarpment
Conference
·
· Geol. Soc. Am., Abstr. Programs; (United States)
OSTI ID:6875434
The Blake Escarpment, the steep, eastern edge of the Blake Plateau, is an erosional features (Paull and Dillon, 1980). Previous work, in the Bahamas, by Freeman-Lynde and Ryan (1984,1985) placed major erosional episodes in the late Cretaceous, the Paleocene and the Oligocene and attributed the majority of the erosion to abyssal currents and variations in the CCD. Samples were taken from the Blake Plateau via the DSRV submersible Alvin during a USGS sampling program from a total of 51 locations grouped into three transects. Thin section, hand sample, and outcrop descriptions, supported by x-ray diffraction and carbon and oxygen isotope analysis yield considerable information on the depositional environments and subsequent erosion of the Blake Plateau. A majority of the samples recovered from the escarpment are of back reef depositional environments, indicating that some of the plateau has been removed. The presence of Eocene, and possibly Miocene, pelagic sediment drapes and fills on shallow-water Cretaceous strata indicate that the Paleocene and Oligocene erosional episodes noted on the Bahama escarpment, have also effected the Blake Plateau. Dissolution in carbonate undersaturated deepwater masses has effected the Blake Escarpment as can be seen by dissolution features on surfaces on the escarpment which have been exposed to sea water. The exposed surfaces are not often covered with a manganese oxide crust, implying that strong currents presently sweeping the area do not significantly erode the escarpment.
- Research Organization:
- Univ. of South Carolina, Columbia (USA)
- OSTI ID:
- 6875434
- Report Number(s):
- CONF-8510489-
- Conference Information:
- Journal Name: Geol. Soc. Am., Abstr. Programs; (United States) Journal Volume: 17
- Country of Publication:
- United States
- Language:
- English
Similar Records
Stratigraphy and structure of southern Blake Plateau, northern Florida Straits, and northern Bahama Platform from multichannel seismic reflection data
Assessment of potential geologic hazards of the northern and central Blake plateau
Terraces on the Florida escarpment: Implications for erosional processes
Journal Article
·
Mon Nov 30 23:00:00 EST 1981
· Am. Assoc. Pet. Geol., Bull.; (United States)
·
OSTI ID:5792654
Assessment of potential geologic hazards of the northern and central Blake plateau
Journal Article
·
Wed Dec 31 23:00:00 EST 1980
· Geol. Surv. Open-File Rep. (U.S.); (United States)
·
OSTI ID:5293464
Terraces on the Florida escarpment: Implications for erosional processes
Journal Article
·
Sun Sep 01 00:00:00 EDT 1991
· Geology; (United States)
·
OSTI ID:5996792
Related Subjects
58 GEOSCIENCES
580300* -- Mineralogy
Petrology
& Rock Mechanics-- (-1989)
ATLANTIC OCEAN
BAHAMA ISLANDS
CARBONATE ROCKS
CARIBBEAN SEA
CENOZOIC ERA
COHERENT SCATTERING
CRETACEOUS PERIOD
DEPOSITION
DEVELOPING COUNTRIES
DIFFRACTION
DISSOLUTION
EROSION
GEOLOGIC AGES
GEOLOGIC HISTORY
GEOLOGY
ISLANDS
MESOZOIC ERA
PETROGRAPHY
PETROLOGY
ROCKS
SCATTERING
SEAS
SEDIMENTARY ROCKS
SEDIMENTS
SURFACE WATERS
TERTIARY PERIOD
WEST INDIES
X-RAY DIFFRACTION
580300* -- Mineralogy
Petrology
& Rock Mechanics-- (-1989)
ATLANTIC OCEAN
BAHAMA ISLANDS
CARBONATE ROCKS
CARIBBEAN SEA
CENOZOIC ERA
COHERENT SCATTERING
CRETACEOUS PERIOD
DEPOSITION
DEVELOPING COUNTRIES
DIFFRACTION
DISSOLUTION
EROSION
GEOLOGIC AGES
GEOLOGIC HISTORY
GEOLOGY
ISLANDS
MESOZOIC ERA
PETROGRAPHY
PETROLOGY
ROCKS
SCATTERING
SEAS
SEDIMENTARY ROCKS
SEDIMENTS
SURFACE WATERS
TERTIARY PERIOD
WEST INDIES
X-RAY DIFFRACTION