Study On The Multi-Temporal Insar Technique And Their Applications In Tectonic Deformation Monitoring

InSAR,as a new type of earth observation technique,has the advantage of all-weather,alltime,high precision,high density,wide coverage,and low cost,and has been widely used in topographic survey and deformation monitoring.However,many factors in conventional InSAR processing,such as temporal decorrelation,spatial decorrelation,atmosphere delay error,DEM error,thermal noise et al.limit the application of InSAR in monitoring surface deformation with high accuracy.Some multi-temporal InSAR(MTI)methods,e.g.PSI and SBAS,emerged in response to eliminating the errors of D-InSAR based on only the pixels with stable reflection and scattering characteristics.This paper will focus on tectonic deformation,which includes three kinds of typical geohazards that have relative slower deformation rate,i.e.large-scale interseismic deformation caused by structural movement,mesoscale regional land subsidence caused by groundwater exploitation,and small-scale deformation caused by tectonic ground fissure.The main technical targets are selection high density coherent target in complex conditions,orbital errors correction,atmospheric delay errors correction,and deformation parameters' estimation based on the weighted model.By using multi-source SAR data,we studied the method to obtain highprecision deformation result using MTI under the condition of large-area,multi-scale deformation and low coherent.Further research has also been developed on the interpretation of the deformation mechanism.Both of the studies extended the breadth and depth of the application of MTI.This article mainly includes:(1)On the foundation of a systematic review and analysis of exiting studies on MTI method,we elaborate the research status of InSAR technology in interseismic deformation monitoring,and the future development of space-borne SAR platform.(2)The paper studies the mathematical model of MTI,gives the function model of multimaster MTI to estimate time series and rate map by weighted least squares method,and establishes the actual operational stochastic model.(3)This paper studies method of atmospheric delay estimation in InSAR.I research the methods of vertical stratification atmospheric delay correction based on ECMWF/ERA-I data.And the methods of turbulence mixing atmospheric delay correction based on adaptive temporal-spatial filter.(4)This paper systematically analyzes main problems of MTI in interseismic deformation monitoring,and research the key technologies of unwrapping error correction,the optimal coherent point selection,initial deformation model building,orbital errors correction and atmospheric delay correction.Finally,I established a complete program of InSAR processing for interseismic deformation monitoring.Based on these research,we using MTI to monitor the interseismic deformation of eastern Altyn Tagh fault,results show that an obvious slip rate near fault,deformation direction is consistent with the left-lateral strike-slip movement.(5)I established a program of InSAR processing for large coverage and multi-scale surface deformation monitoring.I combined several MTI,i.e.Stacking,SBAS,CT,and PI-RATE,in order to monitor the surface deformation of Linfen-Yuncheng basin by using multi-source and multi-track SAR data,and then,selected the optimal monitoring results.Study the methods of combining multi-track InSAR results,I put forward a method of estimating the deviation of multi-track InSAR results based weighted iterative least squares.According to the leveling and GPS measurement data,I correct the reference basis of InSAR results,and the InSAR results of precision can reach millimeter level by validation and calibration estimation.I analysis the spatial distribution characteristics of large-scale tectonic deformation,mesoscale land subsidence and small-scale ground fissure deformation.The facts that the decline of underground water level and the structure features of different strata can reasonable explain the cause of land subsidence.Through analyzing the relationship between ground fissure and active fault,stratigraphic composition,groundwater level,we reasonable explains the formation mechanism of tectonic ground fissures in research area.