Pliocene-Pleistocene biostratigraphy in the Tyrrhenian Sea

The distribution of stratigraphically important calcareous nannofossils and planktonic foraminifera has been investigated in the Pliocene-Pleistocene sequences of ODP Sites 652, 653, and 654 (Tyrrhenian Sea-western Mediterranean). Semiquantitative and quantitative methods have been used, and an optimum relative sequence of bioevents based on the calcareous plankton groups has been established. About 30 bioevents in an interval of 5.0 m.y. are considered widely traceable in the area and reasonably synchronous. On the basis of those events, a correlation among the three investigated sequences is presented.

本研究针对第勒尼安海-西地中海海域ODP站位652、653与654的上新世-更新世地层序列，开展了具有地层学重要性的钙质超微化石（calcareous nannofossils）与浮游有孔虫（planktonic foraminifera）的分布特征调查。本次研究采用半定量与定量分析手段，基于钙质浮游生物类群构建了一套最优的生物事件相对序列。在5.0百万年的地层间隔内，共计约30个生物事件可在该区域广泛追踪且具备合理的同步性。基于上述生物事件，本研究建立了本次所调查的三个地层序列之间的地层对比关系。