南海东北部陆缘基底磁异常反演与解释

Inversion and Interpretation of Magnetic Anomalies at Northeastern Margin Basement of the South China Sea

摘要:

在对南海东北部陆缘的磁场资料展开多尺度分析处理的基础上，结合中生代深度资料，反演求取了前中生代基底的视磁化强度分布.通过对现有综合钻井和地震等资料进行综合分析，论述了基底视磁化强度分布，推测研究区视磁化强度高值带北段可能受制于陆壳，而南段特高值则可能是受次洋壳的改造作用，研究区西部的视磁化强度低值区是一套古生代浅变质岩系，视磁化强度负值区的潮汕坳陷及其东南部基底具有洋壳或准洋壳性质.

Abstract:

Based on multi scale processing and analysis of the magnetic data of northeast continental margin of the South China Sea, the apparent magnetization of pre Mesozoic basement was calculated. Through comprehensive analysis of available drilling and seismic data, the distribution characteristics of apparent magnetization of the basement have been discussed. The northern portion of the high apparent magnetization belt may be subject to continental crust，and the southern portion with special high value may have been resulted from the reform of sub oceanic crust. In the western study area with low apparent magnetization, there is a suit of Paleozoic epizonal metamorphism rock series. Chao Shan depression and its southeast basement with negative apparent magnetization seem to be oceanic crust or quasi oceanic crust by nature.