Seismic Surface Deformation Field And Seismic 3D Deformation Simulation Based On Sentinel-1A Extraction From The Iraq-Iran Border Region

With the rapid development of geophysics,more and more modern space-to-ground technologies and geophysical related theories have been applied to seismic co-seismic ground surface deformation studies.This paper will use space-to-Earth measurement techniques-Differential Synthetic Aperture Radar Interferometry(D-InSAR)and geophysical related theories-Okada elastic half-space homogenous medium dislocation theory and sphere dislocation theory-related calculation procedures for the research of the 7.3 earthquake occurred on the border between Iraq and Iran in the Middle East region and coseismic effect simulation.The coseismic deformation field and the simulated coseismic three-dimensional deformation field within the seismic coverage area were obtained to determine the fault rupture characteristics of the earthquake in the border region of Iran-Iraq.In this paper,a brief introduction to Synthetic Aperture Radar(SAR)and Synthetic Aperture Radar Interferometry(InSAR)is introduced.Based on this,the basic principle of Differential Synthetic Aperture Radar Interferometry(D-InSAR)is introduced,and differential aperture interferometry of synthetic aperture radar is introduced.The principle and specific processing flow of the second rail method(D-InSAR)are described in detail.In this article,the multi-temporal SAR image data of the ESA Sentinel-1A orbit deceleration was selected,and the 90-m resolution SRTM DEM was used as reference data.The GAMMA software and SARscape software data processing platforms were used to obtain the interference results of SAR intensity maps,differential interferograms,filter maps,unwrapped phase maps,and radar line-of-sight(LOS)deformation field maps in the Iraq-Iran earthquake region.The interference results obtained by the two software platforms are compared and analyzed.For related geophysical theories,the paper will use the PSGRN/PSCMP program and sphere dislocation calculation program to simulate the coseismic effect.Firstly,the theoretical foundations of its related dislocation theoretical models:Okada elastic half-space homogenous medium dislocation model(divided into point source dislocations and limited rectangular dislocations)and sphere dislocation model are introduced.By using two different dislocation model correlation calculation procedures,based on the optimal D-InSAR,thethree-dimensional deformation field of the coseismic earthquake in the two Iraq earthquakes was simulated based on the fault slip distribution published by the USGS,and the results of the optimal simulation of the three-dimensional deformation field were selected.The radar LOS is directed to the displacement field,which is then represented as a winding phase,and compared with the D-InSAR extracted differential interference results.Finally,based on the D-InSAR processed differential interference deformation field and the simulated coseismic three-dimensional deformation field,the specific movement characteristics of the Mw 7.3 earthquake on the Iraq-Iranian border region were analyzed.