南海磁性基底分布特征的地球物理研究  

Geophysical research on distribution features of magnetic basements in the South China Sea

作　　者：郝天珧[1] 徐亚[1] 赵百民[1,2] 张永军[1,2] 彭利丽[1] 

机构地区：[1]中国科学院油气资源研究重点实验室,北京100029 [2]中国国土资源部航空物探遥感中心,北京100083

出　　处：《地球物理学报》2009年第11期2763-2774,共12页Chinese Journal of Geophysics

基　　金：国家重点基础研究发展计划项目(973)(2007CB4117-01);国家高技术研究发展计划(863)(2006AA09A101-0201);国家自然科学基金项目(40804016)资助

摘　　要：利用南海最新的磁力资料,在岩石物性分析基础上,选择南海一条典型剖面拟合反演其密度与磁性结构并以拟合结果作为约束,反演全海域磁性基底的宏观分布,对南海磁力数据进行了低纬度化极处理,利用Halo小波基对化极磁异常进行了多尺度分析并依据磁力异常特征进行了磁场分区.根据剖面与全海域磁性基底反演结果认为:南海北部陆缘更倾向于非火山型的构造属性.磁性基底对浅部沉积作用的控制关系在莺歌海一带表现得非常明显.中—西沙和南沙块体的磁性基底特征十分相似,推测在海盆拉张之前,二者为同一块体.We have studied the macro-distribution of magnetic basements in the South China Sea （SCS） based on the latest magnetic data and physical property analysis of rocks. The density and magnetic susceptibility structures along a profile across the SCS were inverted as the constraint to the whole region. The effects of different Reduction To Pole （RTP） methods in low-latitude areas were studied and applied to magnetic data of the study area. The Halo wavelet was used in multi-scale analysis of RTP magnetic data of the SCS. The result shows that the SCS can be divided into five zones according to the characteristics of magnetic anomalies. The northern margin of the SCS is more like a non-vocanic continental margin from the results of magnetic basement inversion and the profile inversion. In the Yinggehai area, the control effect of the magnetic basement to the sedimentary layers is obvious. The characteristics of the magnetic basements of the Zhongsha-Xisha block and Nansha block are very analogous. We infer that they might be of one block before extension of the sea basin.

关 键 词：南海 磁性基底 分布特征 

分 类 号：P318[天文地球—固体地球物理学] P738[天文地球—地球物理学]