文献类型：期刊文献

英文题名：Geochemical Characteristics and Their Marine Environmental and Organic Source Implications for the Lower Cambrian Shales in Guizhou Province, South China

作者：Li, Yan[1]; Wang, Sibo[2]; Xia, Jia[2]; Song, Zhiguang[2,3]

机构：[1] Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yatsen University, Zhuhai, 519082, China; [2] School of Chemistry and Environment, Guangdong Ocean University, Zhanjiang, 524088, China; [3] State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China

年份：2021

卷号：2021

期号：SpecialIssue 9

外文期刊名：Lithosphere

收录：EI(收录号：20221111773309)

语种：英文

外文关键词：Deposition - Paraffins - Sea level - Biomarkers - Oil shale - Phytoplankton - Pyrites - Bacteria - Sulfur compounds

外文摘要：In this study, we conducted systematic analysis of total organic carbon (TOC) content, lipid biomarkers, carbon isotopes of kerogen (δ13Ckerogen), and mineral composition in Niu-ti-tang (?1n) and Pa-lang (?1p) shales from Guizhou Province in order to provide a better understanding of the organic sources and marine environmental condition during deposition of the Lower Cambrian shales of South China. The results show that a broad variety of lipid biomarkers, such as n-alkanes, pristane, phytane, terpanes, hopanes, and steranes, are in these shales, which suggests a signi?cant contribution of various paleobios with bacterial microorganisms and algae thriving under a low-salinity and stable anoxic environment. The negative δ13Ckerogen value (minimum ?36.4‰) and occurrence of pyrite (1–7.5%) and carbonates (2.4–57.3%) indicate that bacterial sulfate reduction prevailed under anoxic conditions during deposition of the Lower Cambrian shales. Moreover, the di?erence in mineral and δ13Ckerogen composition between ?1n and ?1p shales might imply signi?cant changes in primary production and paleoocean environments due to sea-level rise, as shown by the higher average TOC content in ?1p shales (2.52%) compared to that in ?1n shales (1.79%). The covariances of TOC content and mineral and δ13Ckerogen composition suggest that the ?1p shales might have been deposited under a higher sea level associated with high primary productivity, compared to ?1n shales. Thus, high primary productivity driven by sea-level rise is suggested to be the main controlling factor on organic matter enrichment in ?1p shales under stable anoxic conditions. Copyright ? 2022 Yan Li et al. Exclusive Licensee GeoScienceWorld. Distributed under a Creative Commons Attribution License (CC BY 4.0)