THE PRELIMINARY STUDY OF SEGMENTATION OF THE MID-OCEAN RIDGE IN SOUTHWEST SUB-BASIN OF THE SOUTH CHINA SEA
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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。Abstract: 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.
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Key words:
- extinct mid-ocean ridge /
- segmentation /
- transform fault /
- transition zone /
- southwest sub-basin of SCS
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