DInSAR near-fault coseismic deformation field extraction method

Abstract

The invention discloses a DInSAR near-fault co-seismic deformation field extraction method. The method includes the following steps that: step 1, synthetic aperture radar interferometry (InSAR) processing is performed on a synthetic aperture radar (SAR) image that needs co-seismic deformation field region extraction, so that a loss-of-relevance region caused by a strong earthquake can be obtained;step 2, the pixel offset values of the loss-of-relevance region is obtained through dense grid offset calculation and by means of a migration tracking algorithm; step 3, actual offset values are obtained according to the pixel offset values obtained in the step 2, and the actual offset values of all pixels in the loss-of-relevance region can be obtained, and the positions of slave image homonymypoint pairs are calculated, and a resampling process is completed; and step 4, synthetic aperture radar interferometry (InSAR) processing is performed on an image obtained in the step 3, so that a complete coseismic deformation field is obtained. With the method adopted, regional registration and sampling accuracy are significantly improved, the interference loss-of-relevance problem of a fault near field is partially solved, and richer and more accurate near field surface observation data are provided for the inversion of source model parameters.

Description

technical field [0001] The invention relates to InSAR measurement technology, in particular to a DInSAR near-fault coseismic deformation field extraction method. Background technique [0002] Earthquake is a natural phenomenon in which the earth's crust suddenly releases part of the tectonic stress after a long period of accumulated stress; Secondary disasters such as landslides; earthquakes are one of the most destructive natural disasters, which often pose a great threat to the safety of human life and property; accurately monitor and analyze the spatial movement characteristics of seismogenic faults, and obtain earthquake damage intensity and magnitude Such information plays an important role in earthquake monitoring and disaster analysis; and the seismic coseismic deformation field is an important scientific data for accurately understanding the characteristics of seismic activity, so it is a crucial issue to study how to obtain the coseismic deformation field accurately...

AI Technical Summary

Problems solved by technology

[0003] At present, the differential interferometry technique of synthetic aperture radar (DInSAR), which has the characteristics and advantages of all-day, all-weather, and high spatial resolution, is widely used in the acquisition of coseismic deformation fields; however, because strong earthquakes often cause severe ground motion, As a result, there is often a serious InSAR interference loss correlation problem in the earthquake near-fault area; thus, part of the extracted co-seismic surface deformation field is missing; among them, the InSAR interference loss caused by the complete fragmentation of the ground surface due to strong earthquakes and post-earthquake secondary disasters, etc. The correlation cannot be recovered; the InSAR interferometric loss-correlation caused by the excessive non-destructive displacement of the surface can be improved; the loss-correlation problem is caused by the sampling error caused by the inability of the conventional registration model to accurately simulate the near-field migration of the fault

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