甚低频电磁法在草原覆盖区矿产勘查中的应用

Application of very low frequency electromagnetic method to exploration work in grassland-capped areas

在草原覆盖地区进行矿产资源勘查时,甚低频电磁法在一定的地质条件下是间接找矿的有效方法。众所周知,与矿有关的主要地质因素有断裂、破碎带、蚀变、矿化等,它们与围岩在导电性上往往有很大差异,因此,在覆盖厚度不大、人工干扰因素较少等情况下,采用甚低频法可经济、快速地发现并查明这些控矿因素,以达到间接找矿的目的。文章是近些年来笔者在草原覆盖地区进行矿产资源勘查时,使用甚低频电磁法取得的一些间接找矿效果。

The very low frequency electromagnetic （VLF-EM） method, adopted as the means of indirect exploration under certain geological settings, has been proved to be effective in grassland-capped areas. As is well known, the major geological factors for ore formation include tectonic structures, faults, fracture zones, alteration, mineralization etc., which are usually quite different in conductance from those in surrounding rocks. Therefore, when constraining these mineralization-controlling factors under such geoelectric circumstances as capping areas with limited thickness or areas with insignificant human disturbance, we can adopt VLF-EM as a rapid and economical indirect means for mineral exploration. This paper has summed up some indirect ore-prospecting results obtained by the authors in recent years in applying VLF-EM to mineral exploration work in grassland-capped areas.