Grain size and diatom valves in sediment cores KS82-30 and KS82-31

Diatoms were studied quantitatively in six latest Quaternary (~70 kyr B.P. to Recent) piston cores from the westernmost Mediterranean, the Alboran Basin, and the Atlantic region immediately to the west of the Straits of Gibraltar. The Atlantic cores completely lack diatoms. In the Alboran Basin, diatoms are common from late Stage 3 (~27.5 kyr B.P.) to Termination lb (9 kyr B.P.) and in Recent core tops, but are absent in the other latest Quaternary intervals. Maximum accumulation of diatoms and highest abundance of species normally in sediments associated with increased productivity occurred during the latest Quaternary deglaciation, in the first phase of Termination I (~14.8 kyr B.P.).