重磁相关分析应用于区域构造解析

APPLICATION OF CORRELATION ANALYSIS OF GRAVITY AND MAGNETISM TO TECTONIC INTERPRETATION

本文旨在介绍一种简单易行的重磁相关分析方法及其在解析地质构造问题时的作用,该方法在湖南华容地区的应用收到了较好的效果。

On the basis of information of regional geophysical prospcction, some linear features of magnetism and gravity fields may be used to infer location and tectonic elements of tcctosomc briefly. However, if the amounts of the tectonic elements of tectosome need to be determined, the above-mentioned method is incapable of doing the work, bcca se of influence of unuscful anomaly, many indistinct characters in magnetism and gravity fields can't be distinguished. It is well known that correlation analysis is one of classical statistical methods. Da a of gravity and magnetism fields processed by means of correlation analysis may lead to better results. In essence, correlation analysis of gravity and magnetism is that the data of gravity and magnetism fields are processed by means of theoretical anomaly pattern to suppress unuscful information and to highlight useful one in anomaly. In the processing, theoretical anomaly pattern acts as a wave filter. So it is very important to choose a suitable theoretical anomaly pattern. The pattern contains three elements: width, intensity and shape.Difference of intensity affects correlation curve lightly, so docs positive or negative anomaly (shape). Width of the pattern is determined on the basis of studied objects, scales of maps of gravity and magnetism anomaly, characters of regional geophysical fields and so on. The above-mentioned has succeeded in processing data of gravity and magnetism fields of Hualong district in Hunan province, where boundary faults between Mid-Yangtze terrane and South China terrane have been found.