Shear Velocity Structure Research Of US Oklahoma State From Ambient Noise Dispersion And Receiver Function

Recent years,with some companies using water injection method to exploit oil and gas,many earthquakes has happened in Oklahoma State,it has became one of strong seismicity areas in US mainland.These frequent seismic events bring much effect on oil exploitation,safety of buildings and residents' life,so the phenomenon of such frequent earthquakes can't be easily neglected.Shallow structure is important information for doing research on mechanism of earthquake disaster,enlightenment from 1985 Mexico Mw8.1 earthquake which caused huge damage,sediment layers will cause amplified effect on seismic signals' amplitude.Since some researchers' result shows that there are abundant sediment basins in Oklahoma State,combining with frequent earthquakes events happened in here,this place will still facing huge potential seismic hazard in future.We through synthesizing waveform and compare it with real earthquake waveform to indicate amplified effect is existed in this place,So shallow velocity structure research is significant in here.In seismology,joint inversion of ambient noise surface wave dispersion and receiver function is an effect and popular method to explore structure underground.And we use this method to get shallow shear wave velocity structure between surface to 15 kilometer underground of this place.We used shorter period surface wave dispersion than other researchers have used,and it can provide more constraint on shallow region's velocity.Our result is greatly consistency with local geological environment,and the feature of distribution of velocity can be proved in geological time map.Furthermore,our result compares with previous researches' result,like sediment thickness contour,imaging result,they has great correspondence.We also use the test of synthesized waveforms based on our 3D velocity model to compare with real earthquake waveform to prove accuracy of our result.Our result can show clear basins' scope and character of low velocity,it can support a relative reliable shear velocity model.