The analysis of radiolarians from Japan Sea subsurface sediments recovered during Leg 128 of the Ocean Drilling Program reveals that a warm-water assemblage similar to that of the North Pacific was replaced by unique post-middle Miocene faunas probably as a result of the restriction of Oceanographic circulation. The modern fauna was gradually established only in the Pleistocene. No attempt was made to establish the radiolarian zonation because of low species diversity and the absence of generally recognized index forms in the North Pacific. In the diagenetically altered quartz section, however, a radiolarian assemblage correlative to the middle Miocene Cyrtocapsella tetrapera Zone of western Honshu was identified from Hole 799B.

Supplement to: Ling, Hsin Yi (1992): Radiolarians from the Sea of Japan: Leg 128. In: Pisciotto, KA; Ingle, JCJr.; von Breymann, MT; Barron, J; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 127/128(1), 225-236