Methane seepage patterns during the middle Pleistocene inferred from molybdenum enrichments of seep carbonates in the South China Sea

doi:10.1016/j.oregeorev.2020.103701

	Methane seepage patterns during the middle Pleistocene inferred from molybdenum enrichments of seep carbonates in the South China Sea
	Deng, Yinan 1,2,3; Chen, Fang 2,3; Hu, Yu 3,4; Guo, Qingjun 5; Cao, Jun 2,3; Chen, Hong 2,3; Zhou, Jianhou 2,3; Jiang, Xuexiao 2,3; Zhu, Jiang 1
刊名	ORE GEOLOGY REVIEWS
	2020-10-01
卷号	125 页码:19
关键词	Methane seepage Seep carbonate Trace elements Mo enrichment Euxinic condition South China Sea
ISSN号	0169-1368
DOI	10.1016/j.oregeorev.2020.103701
通讯作者	Hu, Yu(huyu@shou.edu.cn) ; Guo, Qingjun(guoqj@igsnrr.ac.cn)
英文摘要	Seepage of methane-rich fluids, are widespread along the continental margins of the world. Intense seepages of methane may lead to the emission of this powerful greenhouse gas into the hydrosphere and atmosphere with implications in the understanding of past dramatic marine environment changes and global warming. However, euxinic environments with sulfidic bottom water as a result of vigorous seepages at ancient cold seeps remain unidentified. Here we report trace element geochemistry and associated mineralogical and carbon and oxygen isotopic data in seep carbonates collected from long drill cores in the South China Sea. Three distinct stages of methane seepages events probably caused by the dissociation of gas hydrates are discernible. Carbonates formed in stage 2 during the Marine Isotope Stage 5 (MIS5) are mainly occurred as aragonite and show extremely high molybdenum (Mo) contents (up to 118 mu g/g), and strong enrichments of authigenic Mo in relative to uranium. These results suggest the presence of intermittent or even permanent euxinic conditions generated by sulfidic bottom water that result from intensive methane seepages. In contrast, mineral compositions and trace element patterns indicate that the carbonates before and after the MIS 5 (stages 1 and 3) form within sulfidic conditions restricted to pore water under relatively lower methane fluxes. Our results highlight extremely intense methane seepages that may potentially result in localized euxinic environments. The inferred euxinic environments imply more amount of massive methane release into the water column than a previous estimation, which was triggered by large-scale dissociation of gas hydrates in the South China Sea during MIS 5.
资助项目	National Natural Science Foundation of China, China[41776066] ; National Natural Science Foundation of China, China[41803026] ; National Natural Science Foundation of China, China[41606048] ; Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China[GML2019ZD0506] ; Yunnan University's Research Innovation Fund for Graduate Students, China[2019z046] ; China Ocean Mineral Resources R&D Association, China[DY135C1-1-04] ; Key Laboratory of Marine Mineral Resources, Ministry of Natural Resources, China[KLMMR-2015-A-03]
WOS关键词	NORTHERN CONTINENTAL-SLOPE ; HYDRATE-BEARING SEDIMENTS ; TRACE-METAL ENRICHMENT ; GAS-HYDRATE ; AUTHIGENIC CARBONATES ; COLD-SEEP ; FLUID SOURCES ; ANAEROBIC OXIDATION ; PORE-WATER ; TEMPERATURE-CHANGE
WOS研究方向	Geology ; Mineralogy ; Mining & Mineral Processing
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000569883100003
资助机构	National Natural Science Foundation of China, China ; Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China ; Yunnan University's Research Innovation Fund for Graduate Students, China ; China Ocean Mineral Resources R&D Association, China ; Key Laboratory of Marine Mineral Resources, Ministry of Natural Resources, China
内容类型	期刊论文
源URL	[http://ir.igsnrr.ac.cn/handle/311030/156925]
专题	中国科学院地理科学与资源研究所
通讯作者	Hu, Yu; Guo, Qingjun
作者单位	1.Yunnan Univ, Res Ctr Earth Syst Sci, Kunming 650091, Yunnan, Peoples R China 2.Guangzhou Marine Geol Survey, MNR Key Lab Marine Mineral Resources, Guangzhou 510075, Peoples R China 3.Southern Marine Sci & Engn Guangdong Lab Guangzho, Guangzhou 511458, Peoples R China 4.Shanghai Ocean Univ, Coll Marine Sci, Shanghai Engn Res Ctr Hadal Sci & Technol, Shanghai 201306, Peoples R China 5.Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China
推荐引用方式 GB/T 7714	Deng, Yinan,Chen, Fang,Hu, Yu,et al. Methane seepage patterns during the middle Pleistocene inferred from molybdenum enrichments of seep carbonates in the South China Sea[J]. ORE GEOLOGY REVIEWS,2020,125:19.
APA	Deng, Yinan.,Chen, Fang.,Hu, Yu.,Guo, Qingjun.,Cao, Jun.,...&Zhu, Jiang.(2020).Methane seepage patterns during the middle Pleistocene inferred from molybdenum enrichments of seep carbonates in the South China Sea.ORE GEOLOGY REVIEWS,125,19.
MLA	Deng, Yinan,et al."Methane seepage patterns during the middle Pleistocene inferred from molybdenum enrichments of seep carbonates in the South China Sea".ORE GEOLOGY REVIEWS 125(2020):19.