三维电阻率成像在小型滑坡探测中的应用

Application of Three-dimensional Resistivity Imaging in Small Landslide Detection

三维电阻率法具有多角度数据覆盖、可适应复杂条件的优点,故将其应用于小型滑坡探测中。利用16×14电极组成的测网,分别采用温纳α、偶极和二极装置对位于浙江丽水的小西村滑坡进行了探测,对采集获得的9744个数据进行了处理和三维反演。基于反演电阻率模型推断该滑坡为顺层滑坡,滑动面上陡下缓,坡脚处沉积层厚度大于上部的,确定了主滑方向,指出了重点预警位置,验证了三维电阻率法探测滑坡的有效性。对比和讨论了3种装置的数据量、数据质量、分辨率、探测深度及适用性,结果表明,温纳法精度高、探测深度浅,二极法探测深度大、精度低,偶极法介于两者之间。该结果对根据探测目标选择恰当的装置有指导意义。

Because of the advantages of multi-angle data coverage and adaptability to complex conditions,the three-dimensional resistivity method is applied to the detection of small landslides.The Xiaoxicun landslide in Lishui,Zhejiang Province was detected by using a measuring network composed of 16×14 electrodes and Wennerα,dipole and dipole devices,respectively.The 9744 data collected are processed and three-dimensional inversion is carried out.Based on the inversion resistivity model,it is inferred that the landslide is a bedding landslide.The sliding surface is steep and descends gently,and the thickness of the sedimentary layer at the foot of the slope is larger than that at the upper part.The main sliding direction and key early warning positions are determined.The validity of the three-dimensional resistivity method for detecting landslides is verified.The data volume,data quality,resolution,detection depth and applicability of the three devices were compared and discussed.The results are as follows.The Wenner method has high precision and shallow detection depth.The dipole method has a large detection depth and low precision,and the dipole method is between the two.The results have guiding significance for selecting the appropriate device according to the detection target.