RADIOLARIA FOSSILS OF THE SURFACE SEDIMENTS IN THE BERING SEA AND ITS SEDIMENTARY ENVIRONMENT
Cheng Zhenbo, Shi Xuefa, Gao Aiguo and Ju Xiaohua (Key Laboratory of Marine Science and Numerical Modeling,First Institute of Oceanography, SOA, Qingdao 266003, China)
Total number 2472, 36 genera and 45 species are distinguished after the radiolaria fossils from 12 surface sediments in the Bering Sea are analysed. The distribution characteristics of radiolaria fossils in the surface sediments is as follows: 1. From the shelf of shallow water to the upper area of continental slope, there are a few radiolaria fossils and monotonous genus and species. 2. In the low area of continental slope, radiolaria fossils are poor in the volcanic cinders and turbidite. 3. The abundance and diversity of radiolaria fossils are high in the clay of basin. The dominant species of radiolaria is Spongotrochus glacialis on the continental shelf. The current, topography, water depth, water temperature etc. are key factors influencing radiolaria distribution. The sources of sediments mainly are terrigenous sediments,biogenic sediments and volcanic sediments in the suvey area and they are mostly from the Kamchatka Peninsula in the east of USSR and Aleutian Islands.