高精度磁测与激电测深在航磁异常查证中的应用

宝音图地区的地层与岩体具有明显的磁性和电性差异,为了解该区航磁异常的地质与地球物理特征,通过1∶1万地面高精度磁法测量,圈定地面磁异常及复核航磁异常的位置,对磁测数据进行化极、延拓等处理,获得磁异常的形态、规模、埋深等特征;选取矿化好的磁异常区段进行激电测深工作,反演矿(化)体在深部的规模及延伸状况;而后通过钻探工程揭露,验证激电反演结果。最后结合地质、激电测深、钻探验证等资料,用Oasis Montaj软件对磁测剖面数据进行2.75D人机联合约束反演,拟合出矿体的形态特征,得出异常体的相对深度、宽度和厚度,为地质找矿提供有利的地球物理依据。

The application of high precision magnetic survey and IP sounding to the aeromagnetic anomaly verification

The strata and rock masses in Baoyintu area show obvious magnetic and electrical differences.In order to understand geolog?ical and geophysical characteristics of the aeromagnetic anomaly,the authors delineated the areas of ground magnetic anomaly and com?posite aeromagnetic anomaly by 1∶10 000 precision ground magnetic survey.The aeromagnetic data processed with methods of reduction to the pole and upward continuation could obtain the magnetic anomaly features such as shape,size and buried depth. The IP sounding could be used to invert the size and extension of the deep orebody or mineralization in the area where there were obvious mineralization characteristics.Then drilling engineering could validate the result of the IP sounding.Finally,combined with the information of geology, IP sounding and drill verification,the authors used Oasis Montaj software to perform human?machine joint constrained inversion for 2. 75D magnetic profile data, fitted out the morphological characteristics, and drew relative depth, width and thickness of the anomaly body, thus providing reliable geophysical basis for ore prospecting.