Figure25. Discovery of the Namibia Opal Paradox: maximum coastal upwelling (in the Quaternary) is not congruent with maximum overall diatom abundance at the sites off Namibia. Proboscia barboi indicates a cold-water influence, as does P. curvirostris. Thalassiothrix-rich sediments and mats are ascribed to varying supply from strong frontal systems with a coastal, Antarctic/subantarctic, and open ocean component. Cycladophora pliocenica and P. barboi in this system suggest Southern Ocean influence. Chaetoceros spores are taken as indicating upwelling, and especially coastal upwelling. A. Sites 1081 and 1082. (Continued on next page.)

Figure 25. Discovery of the Namibia Opal Paradox: maximum coastal upwelling (in the Quaternary) is not congruent with maximum overall diatom abundance at the sites off Namibia. Proboscia barboi indicates a cold-water influence, as does P. curvirostris. Thalassiothrix-rich sediments and mats are ascribed to varying supply from strong frontal systems with a coastal, Antarctic/subantarctic, and open ocean component. Cycladophora pliocenica and P. barboi in this system suggest Southern Ocean influence. Chaetoceros spores are taken as indicating upwelling, and especially coastal upwelling. A. Sites 1081 and 1082.