气候变化领域集成服务门户(CCPortal): Controls on organic matter enrichment in source rocks of the Shahejie Formation in the southwestern Bozhong Sag; Bohai Bay Basin; China

CCPortal

DOI	10.1016/j.palaeo.2020.110026
	Controls on organic matter enrichment in source rocks of the Shahejie Formation in the southwestern Bozhong Sag; Bohai Bay Basin; China
	Yin J.; Xu C.; Hao F.; Wang Q.; Miao Q.; Wang Z.; Zou H.
发表日期	2020
ISSN	0031-0182
卷号	560
英文摘要	With the discovery of the Bozhong 19–6 large gas field in the Bohai Bay Basin, the study of lacustrine source rocks in the southwestern Bozhong Sag has garnered new interest. In this paper, 107 source rock samples of the Paleogene Shahejie Formation (Es) from the southwestern Bozhong Sag were analyzed with organic and inorganic methods and compared with other sags in the Bohai Bay Basin to reveal the depositional environment and controlling factors of organic matter enrichment during the deposition of the Es. The formation of source rocks (average total organic content = 2.76%) was subject to a combination of high organic productivity and enhanced organic preservation. Also, this was reflected by the existence of nutrient elements of P and Ba as well as other high productivity-related elements such as Cu, Zn, and Ni. The moderate Mo enrichment factor, Pr/Ph and low to moderate (C/P)org ratios were an essential part of this organic preservation. Moreover, the evidence we observed for the existence of hydrothermal activities consisted of high contents of quartz and pyrite, large positive Eu anomalies, and enrichment of elements related to hydrothermal fluids. Hydrothermal influence may lead to similarities and fluctuations in water salinity, organic productivity and preservation in the third (Es3) and first (Es1) members of the Es. Hydrothermal fluids may play an essential role in promoting the development of high organic productivity, stable reducing environment, and brackish water (as shown by the range of B/Ga and TS/TOC) in the lakes during the source rock deposition. This paper may provide implications for gas accumulation mechanisms and a complete set of organic and inorganic experimental data for source rock analysis in other lacustrine rift basins. © 2020 Elsevier B.V.
英文关键词	Bozhong Sag; Hydrothermal influence; Organic matter enrichment; Organic productivity; Reducing conditions
语种	英语
scopus关键词	brackish water; depositional environment; gas field; hydrothermal activity; lacustrine environment; nutrient enrichment; organic matter; Paleogene; quartz; salinity; sediment chemistry; source rock; Bohai Sea; Bohaiwan Basin; Bozhong Sag; China
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/150298
作者单位	School of Geosciences, Yangtze University, Wuhan, 430100, China; CNOOC China Limited, Tianjin Branch, Tanggu, 300459, China; China University of Petroleum, Qingdao, 266580, China; State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Fuxue Road NO.18, Beijing, 102249, China; College of Geosciences, China University of Petroleum, Beijing, 102249, China
推荐引用方式 GB/T 7714	Yin J.,Xu C.,Hao F.,et al. Controls on organic matter enrichment in source rocks of the Shahejie Formation in the southwestern Bozhong Sag; Bohai Bay Basin; China[J],2020,560.
APA	Yin J..,Xu C..,Hao F..,Wang Q..,Miao Q..,...&Zou H..(2020).Controls on organic matter enrichment in source rocks of the Shahejie Formation in the southwestern Bozhong Sag; Bohai Bay Basin; China.Palaeogeography, Palaeoclimatology, Palaeoecology,560.
MLA	Yin J.,et al."Controls on organic matter enrichment in source rocks of the Shahejie Formation in the southwestern Bozhong Sag; Bohai Bay Basin; China".Palaeogeography, Palaeoclimatology, Palaeoecology 560(2020).