Cycles of fine-grained sedimentation and their influences on organic matter distribution in the second member of Paleogene Kongdian Formation in Cangdong Sag,Bohai Bay Basin,East China  

作　　者：ZHAO Xianzheng PU Xiugang YAN Jihua JIN Fengming SHI Zhannan CHAI Gongquan HAN Wenzhong LIU Yan JIANG Wenya CHEN Changwei ZHANG Wei FANG Zheng XIE Delu 

机构地区：[1]PetroChina Dagang Oilfield Company,Tianjin 300280,China [2]China University of Petroleum(East China),Qingdao 266580,China [3]Yangtze University,Wuhan 430100,China

出　　处：《Petroleum Exploration and Development》2023年第3期534-546,共13页石油勘探与开发（英文版）

基　　金：Supported by the National Major Research and Development Project(2020YFA0710504,2022YFF0801204);PetroChina Science and Technology Major Project(2019E-26)。

摘　　要：According to the theory of sequence stratigraphy based on continental transgressive-regressive(T-R)cycles,a 500 m continuous core taken from the second member of Kongdian Formation(Kong 2 Member)of Paleogene in Well G108-8 in the Cangdong Sag,Bohai Bay Basin,was tested and analyzed to clarify the high-frequency cycles of deep-water fine-grained sedimentary rocks in lacustrine basins.A logging vectorgraph in red pattern was plotted,and then a sequence stratigraphic framework with five-order high-frequency cycles was formed for the fine-grained sedimentary rocks in the Kong 2 Member.The high-frequency cycles of fine-grained sedimentary rocks were characterized by using different methods and at different scales.It is found that the fifth-order T cycles record a high content of terrigenous clastic minerals,a low paleosalinity,a relatively humid paleoclimate and a high density of laminae,while the fifth-order R cycles display a high content of carbonate minerals,a high paleosalinity,a dry paleoclimate and a low density of laminae.The changes in high-frequency cycles controlled the abundance and type of organic matter.The T cycles exhibit relatively high TOC and abundant endogenous organic matters in water in addition to terrigenous organic matters,implying a high primary productivity of lake for the generation and enrichment of shale oil.

关 键 词：fine-grained sediment high-frequency cycle lamina density organic matter Paleogene Kong 2 Member Cangdong Sag Bohai Bay Basin 

分 类 号：P618.13[天文地球—矿床学]