Late Pleistocene carbonate dissolution in the Venezuela Basin, Caribbean Sea

Conference · Tue Jan 01 04:00:00 EST 1985 · Geol. Soc. Am., Abstr. Programs; (United States)

OSTI ID:6877411

Cofer-Shabica, N B; Peterson, L C

Piston cores from water depths greater than 4000 m in the Venezuela Basin (Caribbean Sea) provide continuous late Pleistocene records of carbonate dissolution and accumulation. The authors examination of multiple dissolution indices indicate that, at least for the last 150,000 years, dissolution of carbonate in the Venezuela Basin has been more intense during interglacial than glacial periods, a pattern opposite to more general observations from the deep Atlantic and Gulf of Mexico. By virtue of its shallow sill depth (1815 m), the Venezuela Basin is relatively isolated from the mainstream of Atlantic thermohaline circulation, and presently is filled with homogeneous, relatively warm (3.8/sup 0/C) waters primarily derived from Upper North Atlantic Deep Water. During the last glacial, the enhanced preservation of carbonate in the Venezuela Basin suggests the presence of a less corrosive, more oxygenated water mass in the Atlantic near sill depth. However, this simple interpretations is potentially complicated by past changes in the rain of biogenic materials from surface waters to the deep basin in what must be an essentially closed system below sill depth. Their observations of increased interglacial dissolution may help to explain previously noted discrepancies in the local glacial to interglacial amplitude of delta/sup 18/O variations recorded by coccoliths and planktonic foraminifera.

• Research Organization: Univ. of Miami, FL (USA)
• OSTI ID: 6877411
• 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

Related Subjects

58 GEOSCIENCES
580100* -- Geology & Hydrology-- (-1989)
ATLANTIC OCEAN
CARBONATE ROCKS
CARIBBEAN SEA
CENOZOIC ERA
DISSOLUTION
DRILL CORES
GEOLOGIC AGES
GEOLOGIC STRUCTURES
PALEOCLIMATOLOGY
PALEONTOLOGY
PLEISTOCENE EPOCH
PRECIPITATION
QUATERNARY PERIOD
ROCKS
SEAS
SEDIMENTARY BASINS
SEDIMENTARY ROCKS
SEPARATION PROCESSES
SURFACE WATERS