ABSTRACT

Radiolarian data from Holocene sediments of the world oceans were fitted to a hypothetical ocean exhibiting characteristics of all oceans. Warm water sphere radiolarians exhibit major poleward boundaries to their distributions at subtropical and polar convergences. Warm water forms exhibit poleward extensions in the western boundary currents. Collosphaerids are enhanced in sediments under the anticyclonic gyres and eastern tropical regions. The Dictyocoryne profunda-truncatum group appears to be indicative of warm water sphere mesotrophic conditions. Cold water sphere radiolarians dominate sediments poleward of the polar convergences and occur in significant percentages under the eastern boundary currents and equatorial divergences. Intermediate and deep water radiolarians appear to be enhanced under the polar cyclonic gyres, eastern boundary currents, and the oceanic divergences and convergences. These radiolarian indices of present oceanographic conditions (currents, divergences, convergences, and oligotrophic to eutrophic conditions) should aid in deciphering similar paleoceanographic conditions.