Analysis Of Crustal Deformation With High Precision GPS

GPS(Global Positioning System)has become one of the main methods to monitor crustal deformation.In the world there are a large number of GPS stations constructed in various regions to provide reliable and accurate data for the study of surface deformation.This dissertation has done a series of systematic researches on data processing and deformation analysis,which is of great significance for deepening GPS applications and serves as a reference for the progress of GPS applications.GPS data processing,coordinate time series analysis and the final result application is the content of this dissertation.This paper introduced the GPS data processing strategy method and the colored noise contained in the GPS time series and the periodic term characteristics.Using the time series analysis software to determine the best noise model.And use the periodic term of GPS vertical time series to establish a model with regional correlation characteristics to improve the accuracy of velocity.The paper study the crustal evolution features of NAPA earthquake on August 24,2016 using deformation strain analysis methods.Using time series analysis theory analysis the type of color noise in PBO(Plate Boundary Observatory).Find the Power law noise is the most consistent.In view of the GPS station estimates the vertical rate of the station by the mode of GPS repeating measurement without considering the effect of the annual seasonal motion,which leads to the accuracy of the vertical rate decrease.Therefore,this paper studies the method that establish the station annual seasonal motion model based on the Continuously Operating Reference Stations(CORS)site coordinate time series.And to correct the vertical rate estimated by the GPS repeating measurement observations.This paper based on the observation data of PBO network of 88 GPS stations in Alaska 2014-2016 for three years,the correctness of the vertical rate is improved by more than 46% when the vertical rate of the GPS repeating station is corrected by the fitting value of annual seasonal motion.Indicating that the method can be used to correct the vertical rate of the GPS repeating measurement station to improve its reliability.Analysis of crustal deformation information by the GPS stations around of the Seismogenic region.It shows that the reduction rate of the baseline pass through of the Napa fault is 9mm/a,and the average shortening rate is gradually reduced before the earthquake.The Green fault in blockage than the eastern faults.The site combination strain parameter show that west-to-east extrusion deformation dominates.The cross-section results show seismic regions are dominated by right-handed shearing,and the Napa fault has obvious atresia features,and the velocity in the direction of parallel faults up to 15 mm/a within 40 km.The results of surface strain,show that the deformation of the crust is dominated by shear deformation and compressive compression.And the seismic region is the high and low value transition.Based on the analysis above,it is concluded that the eastward movement of the focal area of the Napa earthquake appears to be squeezed,and the velocity of the near earthquake slowed down,and the strain accumulation is increased.The difference of horizontal motion between two sides of fault due to dextral shear,and the region is in a high locked state.