西吉县西南山区典型黄土地震滑坡高密度电法物探解译分析

Interpretation analysis of high-density electrical prospecting of typical seismic loess landslides in the southwestern mountainous area of Xiji county

本文运用高密度电法对宁夏西吉县西南山区典型的黄土地震滑坡进行了探测,并结合钻探资料进行验证分析,目的是查明滑坡区域的地层结构、黄土厚度、基岩埋深、富水地段以及空间展布等特征.结果表明:电阻率参数能够很好的反应研究区的地层分布特征,表层疏松干燥的黄土为高阻反映,随着埋深增加,含水量较大的黄土呈现出低阻反映,在黄土与泥岩接触带饱水区呈现低阻反映;滥泥河流域典型的黄土梁斜坡具有阳坡黄土沉积薄、富水层薄、基岩埋深浅的特征,而在阴坡则表现出黄土沉积厚、富水层厚、基岩埋深大的特征.探测结果可有效的应用于黄土地震滑坡的勘察,为进一步开展黄土地震滑坡的成因机理和防治研究提供参考数据.

This thesis selects two typical seismic loess landslides in the southwestern mountainous area of Xiji county to study with highdensity electrical method,also comparative analysis with bore hole columnar section,aims to analysis the stratum structure,buried depth and space distribution of the bedrock surface in the slope area.The results proves that the observations of the resistivity can be well in reflecting stratigraphy distribution.The loose and dry loess in the surface has high electrical resistance,and drops down with water content increases,the contact zone of mudstone and loess is saturated,which has low electrical resistance.The geophysical prospecting result of the typical loess ridge in the Lanni River basin also shows that the characteristics of loess deposition and water-rich zone in the sunny slope are obviously different from the shade slope.The sunny slope are thin in loess thickness and water-rich zone,the buried depth of bedrock is shallow,but the shade slope have thicker loess,water-rich zone and deeper buried depth of bedrock.The high-density electrical method turns out to be a feasible method in loess-mudstone interface landslide exploration,which can provide reliable geophysical basis for further analysis of landslide mechanism and prevention.