Discussion on the rapid formation mechanism and evolution process of methane hydrate-bearing sediments in Shenhu Area of northern South China Sea

doi:10.1016/j.marpetgeo.2017.12.032

	Discussion on the rapid formation mechanism and evolution process of methane hydrate-bearing sediments in Shenhu Area of northern South China Sea
	Guan, Jin-an 1,2,3,4; Liang, Deqing 1,2,3,4
刊名	MARINE AND PETROLEUM GEOLOGY
	2018-03-01
卷号	91 页码:225-235
关键词	Hydrate-bearing sediment Hydrate reaction kinetics Shenhu area Free gas Rapid hydrate formation and accumulation
ISSN号	0264-8172
DOI	10.1016/j.marpetgeo.2017.12.032
通讯作者	Liang, Deqing(liangdq@ms.giec.ac.cn)
英文摘要	Because of free gas migration in sediment pores, the Shenhu seafloor layers in the northern South China Sea is speculated to have experienced some rapid methane hydrate generation and accumulation. In this study, the main hydrate formation is presumed to occur rapidly in the gas-hydrate-liquid three-phase zone. A first-order reaction kinetics mechanism, which controls the hydrate generation, has been coupled into a flow-transportation-reaction model. The methane flux is chosen to be 0.5 mol.m(-2).a(-1), and the scope of the kinetic reaction coefficient ranges from 10(-1) mol.m(-3).MPa-1.a(-1) to 10(2) mol.m(-3).MPa-1.a(-1). Using these basic conditions, two geological scenarios are designed to investigate the hydrate formation within local effective MH distribution area which is 240.150 mbsf. At three moments (800 a, 4 ka and 8 ka) the state of dissolved methane and salt, layer temperature, gas and hydrate saturation, stratum permeability and capillary pressure has been displayed. The effect of kinetic coefficient on gas and hydrate content, and local temperature, has been compared. The phenomenon accompanying transient decomposition at the hydrate formation front has been found in this process. At last, the constant bottom boundary temperature is set to reflect the influence from deep tectonic activity, and the effects have been discussed. The results demonstrate the possibility of a kind of rapid dynamic evolution process and mechanism on hydrate-bearing sediment formation and aggregation. They also present interesting differences between the enclosing and open characteristics of the Shenhu hydrate system.
资助项目	Natural Science Foundation of China[41374149] ; Chinese National Marine Research Program[GHZ2012006003] ; Science and Technology Program of Guangzhou, China[201707010252]
WOS关键词	GAS HYDRATE ; GEOLOGICAL CONTROLS ; CONTINENTAL-SLOPE ; MARINE-SEDIMENTS ; STABILITY ZONE ; POROUS-MEDIA ; ACCUMULATION ; MARGIN ; SOLUBILITY ; SYSTEMS
WOS研究方向	Geology
语种	英语
出版者	ELSEVIER SCI LTD
WOS记录号	WOS:000430886900016
资助机构	Natural Science Foundation of China ; Chinese National Marine Research Program ; Science and Technology Program of Guangzhou, China
内容类型	期刊论文
源URL	[http://ir.giec.ac.cn/handle/344007/23250]
专题	中国科学院广州能源研究所
通讯作者	Liang, Deqing
作者单位	1.Chinese Acad Sci, Key Lab Gas Hydrate, Guangzhou 510640, Guangdong, Peoples R China 2.Chinese Acad Sci, Guangzhou Ctr Gas Hydrate Res, Guangzhou 510640, Guangdong, Peoples R China 3.Chinese Acad Sci, Guangzhou Inst Energy Convers, Guangzhou 510640, Guangdong, Peoples R China 4.Guangdong Prov Key Lab New & Renewable Energy Res, Guangzhou 510640, Guangdong, Peoples R China
推荐引用方式 GB/T 7714	Guan, Jin-an,Liang, Deqing. Discussion on the rapid formation mechanism and evolution process of methane hydrate-bearing sediments in Shenhu Area of northern South China Sea[J]. MARINE AND PETROLEUM GEOLOGY,2018,91:225-235.
APA	Guan, Jin-an,&Liang, Deqing.(2018).Discussion on the rapid formation mechanism and evolution process of methane hydrate-bearing sediments in Shenhu Area of northern South China Sea.MARINE AND PETROLEUM GEOLOGY,91,225-235.
MLA	Guan, Jin-an,et al."Discussion on the rapid formation mechanism and evolution process of methane hydrate-bearing sediments in Shenhu Area of northern South China Sea".MARINE AND PETROLEUM GEOLOGY 91(2018):225-235.