Biogenic“phosphorus”effect of terrestrial lakes and its significance to oil shale during the Carnian period in the late Triassic  

作　　者：Jiyuan You Xiaohu Zhou Yiyao Yang Shanshan Song Yiqun Liu Zhengzhong Liang Yunyun Bai 

机构地区：[1]School of Energy Engineering,Yulin University,Yulin 719000,China [2]Department of Geology,Northwest University,Xi'an 710069,China [3]Youth Innovation Team of Shaanxi University,Yulin University,Yulin 719000,China [4]“Scientist+Engineer”Team of Qin Chuangyuan in Yulin,Yulin University,Yulin 719000,China

出　　处：《International Journal of Sediment Research》2024年第6期960-970,共11页国际泥沙研究(英文版)

基　　金：National Natural Science Foundation of China(Grant No.42062011);Natural Science Foundation of Shaanxi Province of China(Grant No.2022JM-162);Natural Science Foundation in Yulin of Shaanxi Province(Grant No.2023-CXY-142);Doctoral Foundation of Yulin University(Grant No.22GK12).

摘　　要：The Triassic lacustrine organic-rich shale(LORS)in Member 7 of the Yanchang Formation(Carnian stage)in the southern Ordos Basin is relatively well developed.Additionally,its organic matter abundance,lake biomass and biodiversity,exceed the maximum values of the other strata deposited during the same period.Apatite is one of the most important minerals and is closely related to biological activities.However,the types and genesis of the continental sedimentary apatite and its significance to shale oil are not clear.Here,the stratigraphy,petrology,and sedimentology of the phosphorus-bearing rock series in the Ma Quan section are studied and its sedimentary environment and phosphorus formation are discussed.The current research shows that apatite in the study area can be divided into three categories:collophanite,bone fossils,and spherical microfossils.These three types of biogenic“phosphorus”products provide effective records of the transformation of the biological substances into sedimentary organic matter.There are two main formation mechanisms:the direct action of organisms and the interaction between the organisms.Bone fossils and spherical microfossils are formed by the direct action of organisms,while collophanite is formed by the indirect action of organisms.The phosphatization methods of the organisms mainly include“coating”,“replacement”,and“filling”,and the presence of a ubiquitous phosphate filler potentially reflects a sufficient phosphate supply.Apatite also is highly important for the development of organic matter in oil shale.First,it changes the productivity conditions.Second,the apatite in the shell of spherical microfossils has a certain protective effect on the organic matter in the inner cavity.In the current study,the geological processes of collophanite deposition and mineralization are explained,an important basis for prospecting phosphate resources is provided,and a new field for the study of the organic matter enrichment mechanism of source rocks is established.At the same ti

关 键 词：Apatite Lacustrine organic-rich shale(LORS) PHOSPHATIZATION Carnian period in Triassic Ordos basin 

分 类 号：P53[天文地球—古生物学与地层学]