Cariaco Basin
The Cariaco Basin lies off the north central coast of Venezuela and forms the . It is bounded on the east by Margarita Island, Cubagua Island, and the Araya Peninsula; on the north by 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.
The Cariaco Basin is an east-west trending pull-apart basin located on the continental shelf off the eastern coast of Venezuela. It is a deep depression composed of two sub-basins, the eastern basin and the western basin, each of ~1400 m depth, separated by a saddle of ~900 m. To the south, the basin confines with the wide (~50 km) Unare Platform.
It is connected to the open Caribbean Sea through two shallow (~140 m) channels, to the north the (Tortuga Channel) and to the west the (Centinela Channel). Water circulation inside the basin is restricted, which, combined with the high annual primary productivity of the region (~500 gCm−2yr−1), causes the basin to be permanently anoxic, below ~250 m. This naturally occurring anoxic basin allows for sediments to be deposited without bioturbation, forming varves of alternating light and dark color, which correspond to the dry or rainy season. Its unique geography and undisturbed sediment record provides an excellent history of tropical climate change and is particularly sensitive to shifts in the Intertropical Convergence Zone (ITCZ) and has been the subject of extensive paleoclimatological research, amongst other sedimentological studies, geochemical studies, with alkenones,Mg/Ca, and micropaleontological, with foraminifera,pollen and spores,dinocysts and coccoliths.
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