重磁综合推断中南地区隐伏的中酸性岩体  

Deduced the Distribution of the Concealed Acidic-intermediate Rock with Gravity and Magnetic Exploration in the South-central Area

作　　者：刘圣博[1] 罗士新[1] 刘磊[1] 刘慧[1] 陈长敬[1] 

机构地区：[1]中国地质调查局武汉地质调查中心,湖北武汉430205

出　　处：《工程地球物理学报》2013年第6期805-813,共9页Chinese Journal of Engineering Geophysics

基　　金：中国地质调查局计划项目(编号:1212011120919)资助

摘　　要：分析中南地区岩石物性可知,中酸性岩体的平均密度均小于其围岩的密度,视为低密度体,为重力低异常进行圈定中酸性岩体提供了依据;中酸性岩体的磁性变化范围较大,大多数属于弱磁性且存在剩磁影响,因此对航磁数据进行化极用于圈定中酸性岩体效果不佳。为了在一定程度上压制剩磁的影响,文中采用剩余磁异常模量以及磁异常总梯度模数据处理方法进行磁法数据转换。本文以重力负异常特征为主,结合航磁异常转换数据,综合推断中南地区隐伏的中酸性岩体。中酸性侵入岩与银、铜、铅、锌多金属矿产关系密切,这类异常区是间接寻找上述矿产的有利地带。As the mean density of acidic--intermediate rocks is lower than the density of surrounding rocks based on the analysis of the rock property in the south--central area, it can be regarded as low density rock body, which can apparently provide the evidence of spotting the acidic--intermediate rocks through low gravity anomalies. The magnetism of the acidic--intermediate rock has a larger range of variation, and most of it belongs to weak magnetism. At the same time, the rocks are also with remnant magnetism affection, which leads to not good results by reduction to the pole processing. Considering that the ampli- tude of the residual magnetic anomalies and the total gradient magnetic anomaly data pro- cessing can effectively suppress the remnant magnetism, this study combined the amplitude of the residual magnetic anomalies with the total gradient magnetic anomaly data processing method, deduced the distribution of the concealed acidic--intermediate rock with the low gravity anomaly as the main feature and the processed result of magnetic anomaly data as the assistant reference. As is well known, acidic--intermediate rocks are closely related to silver, copper, lead and zinc polymetallic ore resources. Therefore, such anomalies seem tobe favorable places in search for these resources.

关 键 词：中酸性岩体 岩石物性 重力勘探 磁法勘探 磁异常模量 

分 类 号：P631[天文地球—地质矿产勘探]