南海北部东沙海域天然气水合物的初步研究  

A PRELIMINARY STUDY OF GAS HYDRATES IN DONGSHA REGION NORTH OF SOUTH CHINA SEAWT SONG HWT6AI-WTBWT6IN

作　　者：宋海斌[1] 耿建华[2] WANG How-King 张文生[4] 方银霞[5] 郝天珧[1] 江为为[1] 

机构地区：[1]中国科学院地质与地球物理研究所 [2]同济大学海洋地质教育部重点实验室 [3]Institute of Biogeochemistry and Marine Chemistry,Hamburg University,Hamburg D-20146 Germany [4]中国科学院计算数学与科学工程计算研究所 [5]国家海洋局海底科学重点实验室

出　　处：《地球物理学报》2001年第5期687-695,共9页Chinese Journal of Geophysics

基　　金：国家自然科学基金 (4 990 40 0 7);国家海洋局海底科学重点实验室课题基金

摘　　要：利用地震、测井与地温资料综合分析了南海北部东沙海域可能存在的天然气水合物的分布特征 .研究表明 ,在东沙海域地震剖面上出现似海底反射层、弱振幅带等天然气水合物分布标志 ,在声波测井曲线上呈现高速、速度倒转等天然气水合物存在特征 .似海底反射层的深度与 1 1 44站位 ,及平均地温梯度资料得出的稳定带厚度较吻合 .1 1 44站位与 1 1 48站位似海底反射层距海底较深 ,分别为 6 5 4m与 475m .在 1 1 44站位附近 ,弱振幅带的顶界可能代表含天然气水合物沉积层的顶界 ,约在 45 0m左右 .WT By using seismic, sonic logging and geothermal data the distribution characteristics of gas hydrates in Dongsha region north of South China Sea are studied. Bottom simulating reflectors (BSR) and amplitude blanking zone are discovered in seismic profiles. And high-velocity interval and velocity reverse are distinguished in sonic logging curve. The BSR depth is compared with thickness of gas hydrates stability zone from thermal gradient data. The depth of BSR is in agreement with that obtained at ODP site 1144 and 1148, which are 654 and 475 meters below sea floor, respectively. The top of amplitude blanking zone may be related with that of gas hydrates-bearing strata in adjacent region of ODP site 1144 which is about 450 meters below sea floor.

关 键 词：天然气水合物 南海 似海底反射层 弱振幅带 声波测井 温压条件 地温资料 海底沉积物 

分 类 号：P744.4[天文地球—海洋科学] P736.21