综合物探在古河道探测中的应用

Application of comprehensive geophysical exploration in ancient river exploration

因工程地质条件和探测环境的不同,单一物探方法在特定工程区内存在一定的局限性,综合物探手段可显著提高探测的效率和准确性。以南水北调东线二期工程为实例,采用高密度电法和瞬态瑞雷面波法相结合的综合物探手段,对临吴渠渠道两侧进行探测,查明地下古河道的埋深、厚度和延伸范围的可行性。通过对高密度电法高阻异常位置进行瞬态瑞雷面波探测,两种物探手段相互验证,并结合地质勘探成果,基本查明浅埋型地下古河道的存在及相关情况。

The difference of engineering geological conditions and exploration environment,a single geophysical prospecting method may occasionally have certain limitations in a specific engineering area,and comprehensive geophysical prospecting methods can significantly improve the efficiency and accuracy of exploration.In this paper,taking the second phase of the East Route of South-to-North Water Diversion Project as an example,the comprehensive geophysical exploration method combining high-density electrical method with transient Rayleigh wave is used to detect both sides of Linwu Canal,so as to find out the feasibility of buried depth,thickness and extension range of underground ancient river channel.Through the transient Rayleigh wave detection of high-density resistivity anomaly location,the two geophysical methods verify each other,and combining with the geological exploration results,the existence of shallow buried underground ancient river channel is basically found out.