Optimal Selection And Analysis Of High-density Resistivity Detection Device

The high-density resistivity method has the advantages of high work efficiency,complete geoelectric information and large amount of data collection information.It is widely used in foundation exploration,dam safety detection,karst collapse,goaf detection,groundwater detection,etc.Important role and achieved good results.When the high-density resistivity method detects underground geological structures and anomalous bodies through different types of devices,the response characteristics and sensitivity of various types of devices to different forms of geological bodies are different.In order to avoid blindly selecting the device during the actual work in the field,and even affecting the accuracy of the detection result,this thesis selects several typical devices according to the principles of convenience,flexibility,applicability and stability of the device in actual work.The res2dmod forward modeling software performs forward calculations on different types of geoelectric models,and inverts the calculated forward modeling in a targeted manner.Based on the inversion results,it summarizes the use of different devices and predicts that it is in undulating terrain.The responsiveness of various devices to different depths and different forms of geological structures and geological bodies provides a theoretical basis for practical engineering applications.Get the following conclusions:(1)Regardless of whether it is a low-resistance anomaly or a high-resistance anomaly,as the depth of the anomaly continues to increase,the scope of the anomaly becomes larger and the detection accuracy is relatively poorer.(2)The boundary effect has a great influence on all kinds of devices,but the Wenner device has relatively little influence.(3)Each device has a targeted response geological structure,and has poor response to other geological structures.Among them,the Wenner device has the best general applicability and is suitable for general surveys or use in situations where geological data is not abundant.(4)The information of larger geological bodies will cover the information of smaller surrounding geological bodies,among which the high-resistance bodies are more obvious,and the low-resistance bodies are relatively better.(5)The shallow geological body information will cover the deep geological body information,especially the shallow low-resistance information will shield the geological information below it.Finally,on the basis of simulation calculations and experiments,the goaf in a certain district of Wu'an City was detected,how to choose the most suitable device type from the purpose of detection and geological data analysis,and the effects of several device types were compared and analyzed.Finally,on the basis of the drilling data,the apparent resistivity profile contour map and the profile inversion interpretation result map are obtained,and the location and scope of the mined-out area in the detection area are delineated,and finally the high-density resistivity method is used to select the dipole device.It is accurate and feasible in goaf detection.