Influence of water flow on gas hydrate accumulation at cold vents

GIEC OpenIR

	Influence of water flow on gas hydrate accumulation at cold vents
	Cao YunCheng 1; Su Zheng 3; Chen DuoFu 2
	2013-01-01
发表期刊	SCIENCE CHINA-EARTH SCIENCES
ISSN	1674-7313
卷号	56 期号:4 页码:568
摘要	A cold vent is an area where methane-rich fluid seepage occurs. This seepage may alter the local temperature, salinity, and subsequent accumulation of the gas hydrate. Using a kinetic gas hydrate formation model and in situ measurement of temperature, salinity and fluid flux at the southern summit of Hydrate Ridge, we simulate the gas hydrate accumulation at three distinct fluid sites: clam, bacterial mat, and gas discharge sites. At the clam sites (pore water flux 0.8 mol kg(-1)) by the formation of gas hydrate causing the base of the hydrate stability zone to move gradually from similar to 115 to similar to 70 meters below seafloor (mbsf). The gas hydrate saturation at the clam sites is relatively high. The water flux at the bacterial mat sites ranges from 100 to 2500 kg m(-2) yr(-1). The water flow suppresses the increase in salinity resulting in a salinity close to or slightly higher than that of seawater (< 0.65 mol kg(-1)). Heat advection by water flow increases temperature significantly, shifting the base of the hydrate stability zone to above 50 or even 3 mbsf. The gas hydrate saturation is relatively low at the bacterial mat site. At the gas discharge sites, the pore water flux could reach 10(10) kg m(-2) yr(-1), and the temperature could reach that of the source area in 9 min. There is no gas hydrate formation at the gas discharge sites. Our simulative analysis therefore reveals that a lower pore water flux would result in lower salinity, higher temperature, and a shallower base of the hydrate stability zone. This in turn induces a lower gas hydrate formation rate, lower hydrate saturation, and eventually less gas hydrate resources.
关键词	GULF-OF-MEXICO CONTINENTAL-SLOPE CASCADIA MARGIN METHANE HYDRATE WORLDWIDE DISTRIBUTION CHLORIDE ENRICHMENT SOUTHERN SUMMIT THERMAL IMPACT STABILITY ZONE KINETIC-MODEL cold vent fluid seepage temperature salinity gas hydrate numerical simulation
语种	英语
资助项目	[National Basic Research Program of China] ; [Chinese Academy of Sciences] ; [National Natural Science Foundation of China] ; [GIGCAS 135 Program] ; [Scientific and Technological Program of Guangdong Province]
文献类型	期刊论文
条目标识符	http://ir.giec.ac.cn/handle/344007/31809
作者单位	1.中国科学院 2.中国科学院广州地球化学研究所 3.中国科学院广州能源研究所
推荐引用方式 GB/T 7714	Cao YunCheng,Su Zheng,Chen DuoFu. Influence of water flow on gas hydrate accumulation at cold vents[J]. SCIENCE CHINA-EARTH SCIENCES,2013,56(4):568.
APA	Cao YunCheng,Su Zheng,&Chen DuoFu.(2013).Influence of water flow on gas hydrate accumulation at cold vents.SCIENCE CHINA-EARTH SCIENCES,56(4),568.
MLA	Cao YunCheng,et al."Influence of water flow on gas hydrate accumulation at cold vents".SCIENCE CHINA-EARTH SCIENCES 56.4(2013):568.