高密度电法在岩溶勘察中的应用

Application of High Density Electrical Method in Karst Prospecting

岩溶是喀斯特地区一种典型的不良地质体,在工程建设中的危害很大。高密度电法作为岩溶勘察的一种常用方法已被广泛应用。文中通过研究表明,研究区内岩溶以垂直发育为主,局部呈小规模溶洞发育。研究区发现的岩溶异常区,多为直立或近直立低阻异常,陡倾溶蚀裂隙,充填程度普遍较高。基岩节理、裂隙、岩溶等是导电离子良好的通道,决定电阻率的高低。推断断层带上客观存在连续的相对低阻异常带,中部电阻率稍高,岩石块径稍大,岩溶、块石空隙主要发育于断裂带外缘,对建构筑物的影响较大。

Karst is a typical bad geological body in karst area,which is more and more harmful in engineering construction.High-density electrical method has been widely used as a common method of karst exploration.The results of this paper show that the karst in the study area is mainly vertical development,and small scale karst caves are developed locally.Most of the karst anomalies found in the study area are vertical or near-vertical low-resistivity anomalies,and most of them are steep-dip dissolution fractures with high filling degree.Bedrock joints,fissures and karsts are good channels for conducting ions and determine the resistivity.It is inferred that there exists a continuous anomalous zone with relatively low resistivity in the middle of the fault zone,with slightly higher resistivity and larger rock diameter.The karst and stone void mainly develops at the outer edge of the fault zone,which has a great influence on the structures.