Sites 1081, 1082, and 1083 are located on the Walvis Ridge and in the Walvis Basin within an area that is affected by filaments originating from the northern Namibian upwelling cells. Drilling at all sites recovered continuous hemipelagic sections extending into the upper Pliocene (Site 1083) or the upper Miocene (Sites 1082 and 1081; Fig. 2A, Fig. 2B). The biogenic fraction of sediments recovered from these sites contains relatively abundant siliceous microfossils down to the lower Pliocene section. Consequently, an integrated high-resolution stratigraphic framework composed of both calcareous and siliceous microfossil datum events could be established. The mean average sedimentation rates at the Walvis Basin sites range from 11 cm/k.y. for the shallower Site 1082 (water depth: 1279 m) to 7 cm/k.y. for the deeper Site 1083 (water depth: 2178 m). Sediments recovered from the shallow Walvis Ridge Site 1081 (water depth: 794 m), accumulated at a relatively slow rate (5 cm/k.y. on an average), a possible indication of strong bottom currents at this particular setting.
The biostratigraphic framework for the Pleistocene interval is particularly well constrained, with a resolution close to 150 k.y. Sedimentation rates within the last 1.4 Ma are relatively constant for each of the sites. Early Pleistocene and older sediments accumulated at a more variable rate. The Pliocene/Pleistocene boundary between ~2 and 1.7 Ma is characterized by an increased sedimentation rate at all three Walvis sites. This increase in accumulation resulted from an increase in deposition of diatom skeletons. The ecologically-induced absence of several nannofossil index species within the bottom half of Sites 1082 and 1081 strongly hampered the biostratigraphic resolution of the early Pliocene and late Miocene intervals.