重磁方法是地球物理研究中的重要分支,其以位场理论为基础,具有在水平方向上的高分辨率能力并能够提供地壳深部结构的信息,从而对于研究沉积盆地的形成演化过程起着经济有效的作用。文章以东海地区近年的重磁数据为基础,分析了重磁场特征,布格异常值介于-160-460mGal,在正值背景上发育一些局部的重力低圈闭,布格重力异常的主体走向为NE向,磁力异常值介于-200-+500nT,磁力异常的主体走向为NE向。同时,利用磁异常数据计算了东海的磁性基底界面,磁性基底深度在4-12km之间变化,各个地区磁性基底深度起伏变化不同,结合前人研究成果,认为东海地区广泛存在中生界地层。
As important branches of geophysical methods, gravity and magnetic methods are based on the theory of geopotential field and can give the information concerning the deep structure of the crust. They are effective and economic methods to study the formation and evolution of sedimentary basins. Based on the new Bouguer gravity and magnetic data of the East China Sea, the authors analyzed the characteristics of gravity and magnetic anoma- lies as well as their geological significance. The Bouguer gravity anomalies change differently from 160 to 460 regal and some lower gravity anomalies appear in the positive anomaly background field. The magnetic anoma- lies change differently from - 200 to + 500 nT and the main trend of both Bouguer gravity and magnetic anoma- lies are in NE direction. The magnetic basement was calculated and the features of the basement and the geology were analyzed too. The magnetic basement depth changes from 4 to 12 km in different areas. There are Meso- zoic strata in the East China Sea according to the studies in combination with the experience obtained by previous researchers.