Study On Seismic Data Processing For Shallow Active Faults Detection

In recent years earthquake occurred frequently all over the world, resulting in hugelosses.Numerous studies indicate that the seismic belt of active faults are closely related tothese disaster.Shallow active fault detection is an important work carried out to mitigateearthquake disaster.Seismic exploration is one of effective methods for the detection ofshallow active faults. The quality of seismic data processing greatly effect the geodetectionresult.The purposes Layer of the geodetection is very shallow, and most Exploration areas aremainly for the citys or surrounding the citys,and seismic data has the followingcharacteristics:Receive arrangement is shorter，trace distance is smaller, domian frequency ofthe reflected wave is higher shot and outside background interference is stronger, low SNR,low resolution; but active fault detection seismic profiles required to achieve a high SNR,high resolution, which add difficulties for the data processing.This paper based on how to solve static correction problems caused by the geologicalfactors and surface conditions;how to eliminate the the influence caused by shot and receiveconditions;how to improve the signal-to-noise ratio and resolution of shallow seismicdata;and how to do velocity analysis with high-precision.First we analyzed the cause and difficulties of the problems about static correction,andalso analysis parameters of it. This paper analyzed the advantages of chromatography staticcorrection, witch can simulate complex with low velocity structure, more applicable for ofshallow seismic data.If the data is good,refraction static correction also can get a better result.We analyzed the characteristics of the shallow seismic data,Find out the types of noise,Use mutiple methods and seismic processing systems to improve SNR for shallow seismicdata.In order to improve the resolution of shallow seismic data,First we did research on therelation between the domain frequency and resolution of the data.Comparaed differentdeconvolution methods and found out a best flow to improve the resolution of shallowseismic data.Shallow seismic wave’s velocity is very sensitive,we did research to find out aappropriate method and parameters for high-density velocity analysis to obtain accuratevelocity profile,and then acquire a high-quality stacked section.According to above processing methods, with the help of the seismic data processingsystems，We carried out a case study and obtained a good result.