冲绳海槽晚第四纪硅藻生物地层划分与对比

Late Quaternary diatom biostratigraphic subdivision and correlation in Okinawa Trough

本文对冲绳海槽中段B孔岩芯中的沉积硅藻进行了分析,共鉴定出52属166种和变种.根据硅藻属种组成、热带远洋种的相对含量以及整个硅藻植物群的变化特征共划分出9个组合带,并对它们的特征进行了描述;结合14C测年数据,对该岩芯的地层年代归属进行了确定,全新世与晚更新世的界线位于该孔125cm处,上部地层为全新统,下部地层为上更新统;同时与邻近DGKS9603钻孔的硅藻生物地层进行了对比.

Sedimentary diatoms of Core B located in the middle sectionof Okinawa Trough are studied. 166 diatom species and varieties belonging to 52 genus are identified, 9 assemblage zones are subdivided and their characteristics are described based on the diatoms species composition, the relative contents of the pelagic species and the varation of whole diatoms flora. The age of the sediments inCore B is confirmed by the ^(14)C dating and the boundary of Holocene and Pleistocenecan be put at 125cm in depth of the core. The correlation of sedimentary diatom biostratigraphy with the Core DGKF9603 is also studied.