Brief analysis of the geophysical properties of rock and soil in karst area-taking Geely karst collapse area as an example
ZHENG Zhi-jie;CHEN Yi-xiang;GAN Fu-ping;Institute of Karst Geology,Chinese Academy of Geological Sciences / Karst Dynamics Laboratory,MLR & GZAR;
In order to understand the feasibility of the application of the electric prospecting,seismic exploration and gravity prospecting in the karst collapse area of Geely,This paper classified sampled the soil and rock samples in this area, using symmetric small quadrupole,single hole seismic longitudinal wave velocity test and ring method to test and analyse the resistivity,the wave velocity and the density of the soil and rock samples respectively. The results show that the difference of resistivity between aerated soil cave,aerated karst cave and surrounding rock medium is the largest,the resistivity difference between intact limestone and water filled karst cave is the second,the difference of resistivity between silty clay and cultivated soil is the smallest; The density difference between intact limestone and aerated karst cave is the biggest,the density difference between fractured,broken limestone and aerated karst cave is the second,the difference of the density between the gravel bearing silty clay and silty clay is the smallest; the difference of wave velocity between intact limestone and aerated karst cave is the biggest,the difference of wave velocity between fractured,broken limestone and aerated karst cave is second,the difference of the wave velocity between the intact limestone and the fractured limestone is the smallest. The physical property differences among the soil,the rocks and the abnormal bodies are obvious. It is suitable for the development of electric, seismic and gravity prospecting,In addition,this study get the range value,average value,common values and the standard value of resistivity,elastic wave velocity and density of cultivated soil,silty clay,gravel soil,fractured limestone and intact limestone in the Geely karst collapse area,Which provides reliable basis for the interpretation of the geophysical synthetic method in karst collapse area.