The characteristics of BSRs and their derived heat flow on the profile 973 in the northeastern South China Sea

CORC > 海洋研究所 > 中国科学院海洋研究所 > 海洋地质与环境重点实验室

	The characteristics of BSRs and their derived heat flow on the profile 973 in the northeastern South China Sea
	Song Hai-Bin ; Wu Shi-Guo ; Jiang Wei-Wei
刊名	CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION
	2007-09-01
卷号	50 期号:5 页码:1508-1517
关键词	Gas Hydrates Northeastern South China Sea Bottom-simulating Reflection Stability Zone Heat Flow
ISSN号	0001-5733
文献子类	Article
英文摘要	Processing of a recently acquired seismic line in the northeastern South China Sea by Project 973 has been conducted to study the character and the distribution of gas hydrate Bottom-Simulating Reflectors (BSRs) in the Hengchun ridge. Analysis of different-type seismic profiles shows that the distribution of BSRs can be revealed to some extents by single-channel profile in this area, but seismic data processing plays an important role to resolve the full distribution of BSRs in this area. BSR' s in the northeastern South China Sea have the typical characteristics of BSRs on worldwide continental margins: they cross sediment bed reflections, they are generally parallel to the seafloor and the associated reflections have strong amplitude and a negative polarity. The characteristics of BSRs in this area are obvious and the BSRs indicate the occurrence of gas hydrate-bearing sediments in the northeastern South China Sea. The depth of the base of the gas-hydrate stability zone was calculated using the phase stability boundary curve of methane hydrate and gas hydrate with mixture gas composition and compared with the observed BSR depth. If a single gradient geothermal curve is used for the calculation, the base of the stability zone for methane hydrate or gas hydrate with a gas mixture composition does not correspond to the depth of the BSRs observed along the whole seismic profile. The geothermal gradient therefore changes significantly along the profile. The geothermal gradient and heat flow were estimated from the BSR data and the calculations show that the geothermal gradient and heat flow decrease from west to east, with the increase of the distance from the trench and the decrease of the distance to the island arc. The calculated 2 heat flow changes from 28 to 64 mW/m(2), which is basically consistent with the measured heat flow in southwestern offshore Taiwan.; Processing of a recently acquired seismic line in the northeastern South China Sea by Project 973 has been conducted to study the character and the distribution of gas hydrate Bottom-Simulating Reflectors (BSRs) in the Hengchun ridge. Analysis of different-type seismic profiles shows that the distribution of BSRs can be revealed to some extents by single-channel profile in this area, but seismic data processing plays an important role to resolve the full distribution of BSRs in this area. BSR' s in the northeastern South China Sea have the typical characteristics of BSRs on worldwide continental margins: they cross sediment bed reflections, they are generally parallel to the seafloor and the associated reflections have strong amplitude and a negative polarity. The characteristics of BSRs in this area are obvious and the BSRs indicate the occurrence of gas hydrate-bearing sediments in the northeastern South China Sea. The depth of the base of the gas-hydrate stability zone was calculated using the phase stability boundary curve of methane hydrate and gas hydrate with mixture gas composition and compared with the observed BSR depth. If a single gradient geothermal curve is used for the calculation, the base of the stability zone for methane hydrate or gas hydrate with a gas mixture composition does not correspond to the depth of the BSRs observed along the whole seismic profile. The geothermal gradient therefore changes significantly along the profile. The geothermal gradient and heat flow were estimated from the BSR data and the calculations show that the geothermal gradient and heat flow decrease from west to east, with the increase of the distance from the trench and the decrease of the distance to the island arc. The calculated 2 heat flow changes from 28 to 64 mW/m(2), which is basically consistent with the measured heat flow in southwestern offshore Taiwan.
学科主题	Geochemistry & Geophysics
语种	英语
WOS记录号	WOS:000249679300027
公开日期	2010-12-24
内容类型	期刊论文
源URL	[http://ir.qdio.ac.cn/handle/337002/5061]
专题	海洋研究所_海洋地质与环境重点实验室
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China 2.Chinese Acad Sci, Inst Oceanol, Qingdao 266071, Peoples R China
推荐引用方式 GB/T 7714	Song Hai-Bin,Wu Shi-Guo,Jiang Wei-Wei. The characteristics of BSRs and their derived heat flow on the profile 973 in the northeastern South China Sea[J]. CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION,2007,50(5):1508-1517.
APA	Song Hai-Bin,Wu Shi-Guo,&Jiang Wei-Wei.(2007).The characteristics of BSRs and their derived heat flow on the profile 973 in the northeastern South China Sea.CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION,50(5),1508-1517.
MLA	Song Hai-Bin,et al."The characteristics of BSRs and their derived heat flow on the profile 973 in the northeastern South China Sea".CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION 50.5(2007):1508-1517.