气候变化领域集成服务门户(CCPortal): Controlling Factors on Organic Matter Accumulation of Marine Shale across the Ordovician-Silurian Transition in South China: Constraints from Trace-Element Geochemistry

CCPortal

DOI	10.1007/s12583-020-1359-x
	Controlling Factors on Organic Matter Accumulation of Marine Shale across the Ordovician-Silurian Transition in South China: Constraints from Trace-Element Geochemistry
	Qiu, Zhen; Tao, Huifei; Lu, Bin; Chen, Zhenhong; Wu, Songtao; Liu, Hanlin; Qiu, Junli
通讯作者	Tao, HF (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Oil & Gas Res Ctr, Lanzhou 730000, Peoples R China.
发表日期	2021
ISSN	1674-487X
EISSN	1867-111X
起始页码	887
结束页码	900
卷号	32 期号:4
英文摘要	In recent years, significant progress in shale gas exploration has been achieved in the Upper Ordovician (Wufeng Formation)-Lower Silurian (Longmaxi Formation) shales in the Upper Yangtze area, South China. Although many studies have been carried out on the Upper Ordovician-Lower Silurian shales, the controlling factors causing organic matter accumulation of these shales remain controversial. This study uses trace-element geochemistry and sedimentological methods to evaluate terrigenous input, redox conditions and primary productivity to explore the mechanisms of organic matter accumulation. The variation of terrigenous fraction elements (Al, Th and Sc) concentrations reflect a mixed influence of sea-level change and weathering. The sea-level of the Upper Yangtze Sea went through two cycles of transgression to regression during the Ordovician-Silurian transition. The Linxiang Formation, Kuanyinchiao Bed and the upper part of Longmaxi Formation developed during the periods of regression, whereas the Wufeng Formation and the lower part of the Longmaxi Formation developed during the periods of transgression. The paleo-productivity indexes of TOC content, ratios of Ba/Al and P/Al, and redox conditions proxies of Mo concentration, ratios of U/Th and V/Cr generally display similar variation patterns with respect to the sea-level changes. High TOC contents and Ba/Al and P/Al ratios indicate the paleo-productivity was high on the sea surface, as shown by relatively good positive correlations between Th vs. TOC, and Sc vs. TOC. This indicates that the paleo-productivity was controlled by the nutrients input through weathering. The good positive correlations between redox conditions indexes (U/Th and V/Cr ratios) with TOC content reflects reductive preservation conditions (anoxic to euxinic), thus implying they were an important controlling factor for organic matter accumulation. Nevertheless, redox conditions were closely associated with sea level change and organic matter decomposition. Therefore, the sea-level change and weathering were the primary controlling factors for organic matter enrichment across the Ordovician to Silurian transition.
关键词	CONTINENTAL-MARGIN SEDIMENTS BIOGENIC BARIUM FLUXES BLACK SHALES YANGTZE REGION DEPOSITIONAL CONDITIONS LONGMAXI FORMATION APPALACHIAN BASIN GAS EXPLORATION CARBON BUDGET DEEP-SEA
英文关键词	productivity; redox; sea-level change; shale gas; Sichuan Basin; Wufeng-Longmaxi shale
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000686580000014
来源期刊	JOURNAL OF EARTH SCIENCE
来源机构	中国科学院西北生态环境资源研究院
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/253982
作者单位	[Qiu, Zhen; Lu, Bin; Chen, Zhenhong; Wu, Songtao; Liu, Hanlin] Res Inst Petr Explorat & Dev, CNPC, Beijing 100083, Peoples R China; [Qiu, Zhen; Chen, Zhenhong] Natl Energy Shale Gas Res & Dev Expt Ctr, Langfang 065007, Peoples R China; [Tao, Huifei; Qiu, Junli] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Oil & Gas Res Ctr, Lanzhou 730000, Peoples R China; [Wu, Songtao] Key Lab Oil & Gas Reservoirs, CNPC, Beijing 100083, Peoples R China; [Wu, Songtao] Natl Energy Tight Oil & Gas R&D Ctr, Beijing 100083, Peoples R China; [Liu, Hanlin] Peking Univ, Inst Oil & Gas, Beijing 100871, Peoples R China
推荐引用方式 GB/T 7714	Qiu, Zhen,Tao, Huifei,Lu, Bin,et al. Controlling Factors on Organic Matter Accumulation of Marine Shale across the Ordovician-Silurian Transition in South China: Constraints from Trace-Element Geochemistry[J]. 中国科学院西北生态环境资源研究院,2021,32(4).
APA	Qiu, Zhen.,Tao, Huifei.,Lu, Bin.,Chen, Zhenhong.,Wu, Songtao.,...&Qiu, Junli.(2021).Controlling Factors on Organic Matter Accumulation of Marine Shale across the Ordovician-Silurian Transition in South China: Constraints from Trace-Element Geochemistry.JOURNAL OF EARTH SCIENCE,32(4).
MLA	Qiu, Zhen,et al."Controlling Factors on Organic Matter Accumulation of Marine Shale across the Ordovician-Silurian Transition in South China: Constraints from Trace-Element Geochemistry".JOURNAL OF EARTH SCIENCE 32.4(2021).