4th International Conference of Palaeogeography

294 / 2019-08-29 20:45:52

Research Methods About the Sequence Stratigraphy of Deep-water Sediments

Deep-water Sediments；sequence stratigraphy；geochemistry；biomarker compounds

Abstract：The division of deep-water sedimentary sequences has always been a difficult and hot topic in sequence stratigraphy，Traditional methods and means of sequence stratigraphy can not play a very good role in the division of deep-water sedimentary sequence.Based on the previous research results, several methods for dividing deep-water sedimentary sequence are summarized as follows:（1）The deep-water sedimentary sequence can be divided by logging curve data；（2）In the sedimentary strata of interbedded pure mudstone and calcareous mudstone, the sedimentary cycles from pure mudstone to calcareous mudstone are used to divide the sequence；（3）Sequences are divided according to geochemical characteristics, such as changes in Th/U value or TOC content. The smaller the Th/U value or the larger the TOC value, the deeper the depth；（4）Sequence division is based on the degree of mineralization (DOP) of authigenic pyrite. The greater the DOP value, the deeper the depth；（5）Sequence division based on biomarker compounds. At present, the framework of dividing deep-water sedimentary sequences is mainly established by taking lithofacies and their assemblages as the main line, combining mineral composition, geochemical element content and ratio, logging and other indicators, and analyzing them by various methods and verifying each other.