Investigating The Co-seismic Displacements And Source Parameters Of Burma Earthquake Based On The InSAR Measurements

Earthquake is one of the largest natural disasters in the21st century. It can cause great damage to the surface, leading to road fracture and house collapsed, and also brings some secondary disasters, such as landslides and mudslides that has been a serious threat to people’s lives and property. Therefore, it is of great significance to study the co-seismic displacements and source parameters for understanding the earthquake mechanism, and the warning of its prevention and mitigation. The InSAR technique, rapidly developed in recent years, has many advantages such as high spatial resolution, high precision and wide and continual spatial coverage. Compared with the traditional technique, it can provide more detailed rupture information for earthquake deformation monitoring. In this study, we utlize ALOS PALSAR to map the coseismic deformation of Burma earthquake and then inverse the source parameters of this event based on the deformation we obtained. The main contents are as follows:1) The precise co-seismic displacements are extracted, utilizing both the ascending and descend orbit ALOS PALSAR data provided by the JAXA. We use a quadratic surface to remove the long wav elength orbital ramps related to imprecise orbit information. In addit ion to, we also establish a regression model to remove the elevatio n related atmospheric delay.2) The accuracy of the earthquake deformation is analyzed acc ording to the statistical methods. The ascending-orbit displacement h as a little higher error variance (90mm2) than that of the descendin g one85mm2). Both (of their sample covariance function decays to zero at a distance of10km, which imply that the two pixel points become not correlated when their distance is over10km.3) The ascending and descending orbit range and azimuth offse ts are derived respectively with the offset-tracking technique. Conne cting with the InSAR measurements, we determine the uniform faul t model with the strike of70.5°. Meanwhile, a quadtree algorithm i s applied to the coseismic displacements for data resampling to imp rove the inversion efficiency.4) The fault slip distribution and source parameters of the Bur ma earthquake is inferred from the InSAR measurements based on Okada half-space elastic model. The inferring result shows that ther e is large sinistral strike-slip in the fault concentrating the depth ab ove10km, with little bit dip-slip component. The maximum slip of5m is observed at a depth of5km. The inverted seismic moment is2.49×1019N·m (Mw6.8). Figures19, Tables2, References71.