SEDIMENT CORES FROM THE CARIACO TRENCH, VENEZUELA
WOODS HOLE OCEANOGRAPHIC INSTITUTION MA
Pagination or Media Count:
The Cariaco Trench, located within the limits of the continental shelf off the Caribbean coast of Venezuela, is about 160 kilometers long, 40 kilometers wide, and lies 16 to 32 kilometers offshore. Sill depth is about 150 meters maximum depth in the trench is about 1400 meters. Within the trench, waters deeper than 375 meters are anoxic. During cruises in 1957 and 1958, RV ATLANTIS collected over twenty sediment cores, mostly piston type of 3 to 10 meters length, from the trench and its vicinity. The Holocene sediments from the euxinic zone of the trench are mostly grayish-olive and fine-grained either laminated silt-clays or homogeneous silty clays, both types generally containing a paucity of benthic fauna. A lower zone of sediments, at least on the south slopes, consists of yellowish-brown silty clays containing a fair representation of benthic fauna. These appear to have been deposited under normal marine conditions before the basin waters became anoxic and are considered to be late Pleistocene in age. Greatest accumulations of sediments and highest organic contents are believed to occur in the eastern and northeastern parts of the trench.
- Physical and Dynamic Oceanography