南海西南次海盆洋中脊分段特征  

THE PRELIMINARY STUDY OF SEGMENTATION OF THE MID-OCEAN RIDGE IN SOUTHWEST SUB-BASIN OF THE SOUTH CHINA SEA

作　　者：李细兵[1,2] 吴振利[3] 李家彪[3] 

机构地区：[1]南京大学地球科学与工程学院,南京210093 [2]江苏省地震局,南京210014 [3]国家海洋局第二海洋研究所,杭州310012

出　　处：《海洋地质与第四纪地质》2013年第3期101-107,共7页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金项目(41106053);国家海洋局第二海洋研究所科研业务专项(JT201101)

摘　　要：通过对南海西南次海盆的古洋中脊地貌、重力、磁力异常的分析,确定是一个带有中央裂谷性质的古扩张中心,其转换断层两侧分别在地貌、重力、磁力上表现出不同的特征。根据这些特征,沿古洋中脊识别出4条转换断层,对所有转换断层的性质进行了分析,特别对第4条转换断层的性质做了详细探讨,认为该转换断层是西南次海盆中大陆裂谷与洋壳相互演化的一个转换带,这可能意味着该转换带两侧地壳结构属性会有所不同。According to the analysis of the geomorphology,gravity,magnetic data of the extinct mid-ocean ridge in southwest sub-basin of the South China Sea（SCS）,a relict rifting center is found in the study area,of which the feature is similar to that of Atlantic mid-ocean ridge.Four transform faults are identified along the mid-ocean ridge in spatial location.Each of the transform faults shows distinct geophysical features compared with the others.The fourth one is specially discussed in details.It might be an important transition zone between the continental rifting and sea floor spreading,which implies a different crustal structure on both sides of the fault.

关 键 词：古洋中脊 分段性 转换断层 转换带 南海西南次海盆 

分 类 号：P736.1[天文地球—海洋地质]