Tracing the evolution of seep fluids from authigenic carbonates: Green Canyon, northern Gulf of Mexico

CORC > 南海海洋研究所 > 中国科学院南海海洋研究所 > 中科院边缘海地质重点实验室

	Tracing the evolution of seep fluids from authigenic carbonates: Green Canyon, northern Gulf of Mexico
	[Bian, Youyan ; Chen, Duofu] Chinese Acad Sci, CAS Key Lab Marginal Sea Geol, Guangzhou Inst Geochem, Guangzhou 510640, Guangdong, Peoples R China ; [Feng, Dong ; Chen, Duofu] Chinese Acad Sci, CAS Key Lab Marginal Sea Geol, S China Sea Inst Oceanol, Guangzhou 510301, Guangdong, Peoples R China ; [Roberts, Harry H.] Louisiana State Univ, Inst Coastal Studies, Dept Oceanog & Coastal Sci, Sch Coast & Environm, Baton Rouge, LA 70803 USA ; [Bian, Youyan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China
刊名	MARINE AND PETROLEUM GEOLOGY
	2013
卷号	44 页码:71-81
关键词	Authigenic carbonate Cold seep Carbon and oxygen isotope C-14 dating Gulf of Mexico
ISSN号	0264-8172
通讯作者	bianyouyan@gig.ac.cn ; feng@scsio.ac.cn ; hrober3@lsu.edu ; cdf@gig.ac.cn
中文摘要	Authigenic carbonates from hydrocarbon seeps are unique long-term archives of past fluid flow. The studied samples were collected from Green Canyon block 140 at a water depth of 260 m in the Gulf of Mexico. Petrography, X-ray diffraction, stable isotopes and C-14 dating were applied to assess the evolution of seep activity and potential driving forces. The carbonates are dominated by high-Mg calcite (HMC) and aragonite, with a minor amount of low-Mg calcite (LMC) and dolomite. Petrographically, peloids, clotted microfabric, acicular aragonite and a variable content of bioclasts were observed. Three types of carbonates are recognized. Structure I carbonates, with C-14 ages from 46.5 ka to 25.8 ka BP, are characterized by delta C-13 values from -23.2 parts per thousand to 5.1 parts per thousand, suggesting multiple carbon sources that include thermogenic methane, biodegraded crude oil, seawater and residual CO2 from methanogenesis at greater depth. In contrast, Structure II carbonates formed between 17.6 ka and 11.7 ka BP and have delta C-13 values varying from -22.2 parts per thousand, to -8.8 parts per thousand, suggesting carbon sources similar to those of Structure I carbonates but with a negligible influence of residual CO2 from methanogenesis. In addition, the presence of LMC in this type of carbonate may be associated with brine seepage. Structure III carbonates among the youngest of the samples analyzed with C-14 ages of 1.2 ka BP. These carbonates have the most negative delta C-13 values ranging from -36.1 parts per thousand to -26.8 parts per thousand, suggesting that thermogenic methane is the primary carbon source. The majority carbonates of both Structure I and II are slightly O-18-enriched, which is most likely related to the incorporation of water from dehydration of clay minerals. The considerable range of mineralogical and isotopic variations of the studied carbonates highlights the local control of the seepage flux. It is proposed that factors affecting the activity of hydrocarbon seeps are sea level changes and salt movement. The combination of petrography, stable isotopes, and dating approach used here, highlights that these are valuable tools to assess the variability of past fluid flow at hydrocarbon seeps. (C) 2013 Elsevier Ltd. All rights reserved.
学科主题	Geosciences, Multidisciplinary
资助信息	The seep carbonates analyzed in this study were obtained on the cruises sponsored by the Bureau of Ocean Energy Management (BOEM; formerly Minerals Management Service). The study was partially supported by the Knowledge Innovation Program of CAS (KZCX2-YW-GJ03), the NSF of China (Grants: 91228206 and 91028012), "Hundred Talents Program" of CAS, and GIGCAS 135 project Y234021001. We are grateful to Drs. C. Shen and F. Wang (both GIG, CAS) for technical assistance during the experiments. Furthermore, we thank Editor Dr. P. Gianolla, reviewer Dr. A. Mazzini and one anonymous reviewer for their helpful comments that greatly improved an earlier version of this manuscript. This is contribution No. IS-1653 from GIGCAS.
原文出处	ELSEVIER SCI LTD
语种	英语
WOS记录号	WOS:000320294700007
公开日期	2015-01-22
内容类型	期刊论文
源URL	[http://ir.scsio.ac.cn/handle/344004/11129]
专题	南海海洋研究所_中科院边缘海地质重点实验室
推荐引用方式 GB/T 7714	[Bian, Youyan,Chen, Duofu] Chinese Acad Sci, CAS Key Lab Marginal Sea Geol, Guangzhou Inst Geochem, Guangzhou 510640, Guangdong, Peoples R China,[Feng, Dong,et al. Tracing the evolution of seep fluids from authigenic carbonates: Green Canyon, northern Gulf of Mexico[J]. MARINE AND PETROLEUM GEOLOGY,2013,44:71-81.
APA	[Bian, Youyan,Chen, Duofu] Chinese Acad Sci, CAS Key Lab Marginal Sea Geol, Guangzhou Inst Geochem, Guangzhou 510640, Guangdong, Peoples R China,[Feng, Dong,Chen, Duofu] Chinese Acad Sci, CAS Key Lab Marginal Sea Geol, S China Sea Inst Oceanol, Guangzhou 510301, Guangdong, Peoples R China,[Roberts, Harry H.] Louisiana State Univ, Inst Coastal Studies, Dept Oceanog & Coastal Sci, Sch Coast & Environm, Baton Rouge, LA 70803 USA,&[Bian, Youyan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China.(2013).Tracing the evolution of seep fluids from authigenic carbonates: Green Canyon, northern Gulf of Mexico.MARINE AND PETROLEUM GEOLOGY,44,71-81.
MLA	[Bian, Youyan,et al."Tracing the evolution of seep fluids from authigenic carbonates: Green Canyon, northern Gulf of Mexico".MARINE AND PETROLEUM GEOLOGY 44(2013):71-81.