The distribution of Recent Radiolaria in surficial sediments of the continental margin off northern Namibia

Abstract

47 Species of radiolaria have been identified from 30 surface sediment samples collected along transects across the continental margin of northern Namibia between the Kunene River and Walvis Bay. From the distribution patterns of the 24 most abundant species, it was possible to identify a warm water, high salinity population and a cold water, low salinity population. The distribution patterns of each population shows a close correspondence with the known positions of the Angola Current (warm, high salinity water) and the Benguela Current (cold, low salinity water) respectively. Two other trends are apparent from the overall radiolaria distribution; dilution of the nearshore samples by terrigeneous input and a strong preference for open ocean conditions. There is no apparent correlation with upwelling.