Cariaco Basin

The Cariaco Basin lies off the north central coast of Venezuela and forms the Gulf of Cariaco. It is bounded on the east by Margarita Island, Cubagua Island, and the Araya Peninsula; on the north by La Tortuga Island and the Tortuga Banks; on the west by Cape Codera and the rocks known as Farallón Centinela; and on the south by the coast of Venezuela.

It is a naturally occurring anoxic basin where the sediments are deposited without oxygen, thus preserving organic matter which would otherwise be converted by bacteria. The Cariaco Basin is a natural sediment trap, and the varves record how much organic matter is produced in the overlying waters year by year. Because it is one of the largest anoxic basins in the world, it is the subject of much paleoclimatological, chemical oceanographic, and biological research.

References

• Smoak, JM, Benitez-Nelson, C., Moore, WS, Thunell, RC, Astor, Y. and F. Muller-Karger (2004) “Radionuclide fluxes and particle scavenging in Cariaco Basin” Continental Shelf Research 24, 1451-1463.
• Tedesco, K. and Thunell, R., (2003) “Seasonal and interannual variations in planktonic foraminiferal flux and assemblage composition in the Cariaco Basin”, Venezuela. Journal of Foraminiferal Research 33, 192-210.
• Thunell, R. and others, (2000) “Organic carbon fluxes, degradation, and accumulation in an anoxic basin: Sediment trap results from Cariaco Basin”, Limnology and Oceanography , Vol. 45, No. 2, 300-308.
• “This Week in Science” Science 8 December 2000: Vol. 290. no. 5498, p. 1853