花岗岩地区浅部地下水井位的快速确定

文章探讨在花岗岩地区地下水井位的快速定位问题，结合工程实践，采用三极电阻率测深法和天然电场选频法开展综合探测研究。首先实施三极电阻率测深剖面工作，对采集结果进行二维有限元反演研究，获得二维测深断面上低阻导电体的分布规律；在测深剖面上进一步开展天然电场选频法剖面勘探工作，得到低阻含水构造的水平精确位置，并进一步开展选频测深法的实践。后期的成井结果表明:三极电测深勘探成果的剖面异常比较直观，选频法则在异常体的地表水平定位方面比较精确，施工非常方便，两种方法相结合对地下水进行综合勘探是一种行之有效的办法。

Fast determination of shallow groundwater wells in a granite area

The main purpose of this paper is to rapidly prospect shallow groundwater by using a three-pole resistivity sounding device and the frequency selection method of natural electric field in a granite area, where groundwater is relatively poor. At first, on the basis of data of three-pole resistivity sounding, the 2D finite element inversion was studied, and the distribution of the low resistivity conductive bodies on 2D depth sounding section was obtained. Secondly, the frequency selection method of natural electric field was carriout on the same sections and the accurate horizontal position of the low resistivity water bearing structure was obtained. Thirdly, the sounding of the frequency selection method was used to determine the depth of the abnormal body. Subsequent drilling results show that the anomaly section of three-pole sounding is very intuitive, and the frequency selection method is a good method to determine the accurate horizontal position of the anomalous body and it is very simple in field work. The combination of the two methods is an effective way to explore groundwater in granite areas.