Research on geohistorical changes of Phanerozoic oceanic environments by means of radiolarians

本次合作研究（A）的主要成果如下：（1）通过对洋盆样品和陆地样品的研究，古生界和中生代放射虫生物地层学取得了进展。(2)根据对太平洋和印度洋放射虫通量的测量，阐明了季风与洋流上升流的关系。(3)部分建立了古生代和中生代放射虫古生物地理，特别是在侏罗纪时期划分了特提斯和北方放射虫省。(4)在浅海沉积相和深海远洋沉积相研究了古生代大型化石灭绝与二叠纪-三叠纪界线放射虫动物群变化的关系。(5)分析了三叠系-侏罗系层状硅质岩系的沉积过程，并从气候变化的角度探讨了它们的旋回沉积作用。(6)收集了有关日本放射虫研究的放射虫文献数据库。(7)1992年8月24 -25日举行的IGC-92国际放射虫学术讨论会和1994年10月20 -24日举行的INTERRAD VII国际放射虫学术会议都是在本合作研究的支持下召开的（A）。

The results from this Co-operative Research (A) are summarized as follows :(1) Radiolarian biostratigraphies of the Paleozoic and Mesozoic progressed through researches on ocean basin samples and on land ones.(2) On the basis of measurements of radiolarian flux in the Pacific and Indian Ocean, it was clarified the relationship between monsoon and up-welling of ocean currents.(3) Paleozoic and Mesozoic radiolarian paleobiogeography was partly setup, especially Tethys and Boreal radiolarian provinces were recognized during Jurassic time.(4) Relationship between Paleozoic macro fossils extinction and radiolarian fauna change across the Permian and Triassic boundary was examined in shallow marine sedimentary faces and pelagic deep sea faces.(5) Sedimentary process of Triassic-Jurassic bedded chert sequence was analyzed, and the cyclic sedimentation of them was discussed from a viewpoint of climatic change.(6) Collection of data base of radiolarian literatures concerning Japanese radiolarian research was carried out.(7) International radiolarian symposium of IGC-92 (1992.8.24-25) and INTERRAD VII Meeting (1994.10.20-24) were held with support of this Co-operative Research (A).