Currently,seismic explorations is the main geophysical prospecting method for detecting active fault lines in cities.In the detection of the active faults in Xinyi City,the wave reflected from the top of bed rock can only be recognized using P-wave reflection due to the thin overburden in local area.In general,it is difficult to determine the exact location of a fault and the burial depth of the upper breaking point based on the change of a single coaxial axis in seismic reflection profile.The method of S-wave reflection is characterized by high resolution and strong stratification capability,which can make up for the shortcomings of P-wave reflection exploration,thus improving the precision of exploration.In addition,there exist strata of two different ages on both sides of some faults in this exploration area,and there are obvious differences in velocity between them.The seismic velocity profile obtained by seismic tomography can reflect the changes of underground velocity structures and also reveal the existence of shallow faults.Through this comparison and comprehensive analysis of the results obtained by these geophysical prospecting methods and the combination of geological data,the ideal geophysical prospecting results and sound exploration results are reached.
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