Productivity of the benguella upwelling in the pleistocene: Evidence from benthic foraminifers

The taxonomic composition of the benthic foraminifers studied in 36 samples of Pleistocene sediments from DSDP Hole 362 drilled in Leg 40 of the D/V Glomar Challenger made it possible to divide the section into the lower and upper Pleistocene units. The variations in the relative proportions of the planktonic and benthic foraminifers and the abundance, diversity, and taxonomic composition of their benthic taxa imply that the Benguella Current in the Walvis Ridge area was located in the early Pleistocene westward of its present-day position, and the upwelling was more intense and its productivity was higher as compared with these parameters in the late Pleistocene. At the onset of the late Pleistocene, the Benguella Current occupied its present-day position with the intermediate waters ascending to the surface, which resulted in the decline of the upwelling’s productivity.