瞬变电磁法在岩溶地下水运移通道勘探中的应用研究

Application of transient electromagnetic method in exploration of karst groundwater migration channels

岩溶场地地下水运移通道比较复杂,岩溶地区地表水受污染进入地下水径流系统污染地下水,为避免地下水进一步污染扩大,因此探测岩溶地下水运移通道很有必要。地质调绘及理论分析的基础上,沿岩层走向平行和垂直方向布置58探测剖面线、765个探测点用瞬变电磁法进行探测,并通过对探测异常点进行钻孔验证研究工作。研究表明:探测结合电阻率高低推测沿南北向展布的3条主要断裂或断裂破碎带和18个溶洞,钻孔验证与瞬变电磁法探测解译结果相吻合,瞬变电磁法探测及钻孔验证3条断裂或断裂破碎带是场地岩溶地下水运移的主要通道。证明在岩溶地区采用瞬变电磁法探测岩溶地下水运移通道是可行的。

The groundwater migration channels in karst areas are relatively complex,and the surface water in karst areas is polluted and enters the groundwater runoff system to pollute the groundwater,to avoid further pollution and expansion of groundwater,it is necessary to explore the groundwater migration channels in karst areas.On the basis of geological mapping and theoretical analysis,58 detection profile lines and 765 detection points were arranged parallel and vertical to the direction of the rock strata,and transient electromagnetic method was used for detection,and research work was conducted to verify the detection of abnormal points through drilling.Research has shown that:The three major fracture or fracture fracture zones and 18 caves spread along the north-south direction are inferred by the combination of resistivity level of the probe,and the results of the borehole verification and the interpretation of the transient electromagnetic method probe match,and the three fracture or fracture fracture fracture zones verified by the transient electromagnetic method probe and the boreholes are the main channels for the transportation of karst groundwater in the site.It is proved that it is feasible to use transient electromagnetic method to detect karst groundwater transport channels in karst areas.