This paper probed into the sea-level changes from the latest Ordovician to the earliest Silurian and thesubdivision of the Ordovician-Silurian boundary based on the study of biostratigraphy, chemical stratigraphyand sequence stratigraphy.

本文通过生物地层、化学地层和层序地层的研究，对晚奥陶世晚期至志留纪初期的海平面变化以及奥陶／志留系界线的划分进行了探讨。

With the improvement of related research resolution overseas, plenty of new data are accumulated, then the neccarity and importance of doing high precision planktonic foraminifera biostratigraphy research is emerged gradually.

随着国外相关研究精度的提高以及新资料的不断积累,对藏南海相白垩系进行高精度的浮游有孔虫生物地层研究的必要性日益凸显。