Paleoenvironment evolution and organic matter enrichment mechanisms in the first member of the Qingshankou Formation,Songliao Basin,China

作     者：Ying LI Min WANG Yu YAN Xin WANG Jinyou ZHANG Xuefeng BAI Yuchen ZHANG Jiaheng XUE Junsheng FEI Lianbin ZHANG Guojun WANG Ying LI;Min WANG;Yu YAN;Xin WANG;Jinyou ZHANG;Xuefeng BAI;Yuchen ZHANG;Jiaheng XUE;Junsheng FEI;Lianbin ZHANG;Guojun WANG

作者机构：School of GeoscienceChina University of Petroleum(East China)Qingdao 266580China Shandong Provincial Key Laboratory of Deep Oil and GasQingdao 266580China Exploration and Development Research Institute of Daqing Oilfield Co Ltd.Daqing 163712China Exploration DivisionPetroChina Daqing Oilfield CompanyDaqing 163453China Department of PhysicsXiamen University MalaysiaBandar Sunsuria 43900Malaysia 

出 版 物：《Frontiers of Earth Science》 (地球科学前沿（英文版）)

年 卷 期：2024年第18卷第2期

页      面：364-383页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：funded by the National Natural Science Foundation of China(Grant Nos.42072147 and 41922015) the Fundamental Research Funds for the Central Universities(No.22CX07001A) 

主　　题：major and trace elements paleoenvironment evolution OM enrichment mechanism lacustrine shale Songliao Basin Qingshankou Formation 

摘      要：Organic matter is the basis for oil and gas generation,and the depositional environment controls its *** first member of the Qingshankou Formation(K_(2)qn^(1))in Songliao Basin has a thick organic-rich shale and so is an important target section for shale oil exploration and *** the Gulong Sag,shale samples from this unit were collected over the full length of the *** characterization of the environments of deposition(EOD)of K_(2)qn^(1)was improved by utilizing lithological characteristics,thin section observations,elemental compositions,and organic carbon *** with the normalization coefficients proposed in this paper,an organic matter correlation model was established to elucidate the factors that influence organic matter *** the bottom to the top of K2qn1,the lake depth gradually becomes shallower,the primary productivity first decreases and then increases,the reducing conditions become stronger and then weaker,the water salinity gradually decreases,the climate first becomes semi-humid and then warm and humid,and the input of terrigenous debris first decreases and then increases.A major marine transgression at the base of the K_(2)qn^(1)᾽s brought in nutrients to increase primary productivity,and the density-stratified reducing environment preserved and enriched organic *** primary productivity occurred during the middle of the deposition of the K_(2)qn^(1),while terrigenous input is *** matter is preserved in reduced deep lake environments,resulting in organic matter-rich black *** lake became shallower,and the salinity decreased in the upper part of K_(2)qn^(1).Benthic organisms rapidly multiplied,consuming large amounts of oxygen and destroying the previously depositional environment,resulting in a reducing environment disturbed by benthic organisms with poor preservation conditions and the lowest organic matter content.