Resistivity tomography is a part of the methods for conducting fault detection in urban areas. In this paper, the application of resistivity tomography to the detection of concealed faults in sedimentary areas was attempted with the fault detection of the Tianjin Canal as an example. The Wenner symmetrical quadrupole device (Wenner α) was employed to data acquisition. In order to obtain higher quality raw data, the authors adopted a number of targeted measures in the field construction. Data processing and inversion adopted a wide range of engineering circles. Using the RES2DINV software, the authors obtained a more reliable resistivity tomography profile. In the geological interpretation of the section, detailed analysis was carried out based on borehole data of the survey area in comparison with the results of shallow artificial earthquakes. The results show that the Jiyunhe fault is a Quaternary fault and shows a definite segmentation. The shallowest upper fault point in the northern section is about 25 m deep, which is a late Pleistocene active fault, and the southern section is about 55 m,which is a middle late Pleistocene fault. This probing work shows that the use of resistivity tomography for the detection of concealed faults in the sedimentary area can achieve good results, but in the process of geological interpretation, the sedimentary evolutionary environment, the geological structure of the basement, and the conductive ion density of the formation should be closely combined with each other. The impact is particularly dependent on other detection results to ensure the harmonization of relevant consequences.
高武平, 闫成国, 张文朋, 王志胜. 电阻率层析成像在沉积区隐伏断层探测中的应用[J]. 物探与化探, 2020, 44(6): 1352-1360.
GAO Wu-Pin, YAN Cheng-Guo, ZHANG Wen-Peng, WANG Zhi-Sheng. The application of high density electrical method to concealed fault detection in sedimentary plain. Geophysical and Geochemical Exploration, 2020, 44(6): 1352-1360.
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