基于GIS的当雄同震InSAR形变场分析

InSAR技术对同震形变的量测达到了厘米级的精度,但在数据后处理和结果分析方面仍然存在明显的不足。采用可对空间信息进行存储、管理及分析等功能的GIS,对InSAR数据获取的2008年10月6日16时30分西藏自治区当雄县MW6.3地震的同震形变场进行分析。结果表明:(1)GIS可对多源数据进行有效管理;(2)可以确定当雄地震的震中位置;(3)可获取沉降区的最大形变量;(4)可确定主要的形变区间;(5)可将形变结果进行三维展示。GIS可有效地弥补InSAR数据后处理、数据分析及成果展示方面的不足。

Analysis of the InSAR Earthquake Deformation Field in Damxung Based on GIS

InSAR technology can achieve centimeter-level accuracy in terms of coseismic deformation measurement but presents disadvantages of complex data post-processing and consequent explanation. The results of GIS spatial analysis are extremely rich, and its data management function is fairly powerful. This paper''s main objective is to use GIS technology to analyze the results of InSAR data, strengthen results management, and improve the preciseness of analytical results to enable a diverse display of the consequent data. A M_W6.3 earthquake that occurred at 16:30 on October 6, 2008 in Damxung County in the Tibet Autonomous Region is taken as an example. Using ENVISAT ASAR level 0 and SRTM DEM data groups, the coseismic deformation field of the earthquake was obtained via two-pass differential interferometry with the InSAR method. The basic geographic data of the study area, including river, boundary line, and road and boundary conditions, were collected. GIS data analysis capabilities were adopted to explain the seismic deformation field extracted by InSAR data. Using the GIS management function, effective management was first conducted on the multi-source data, after which the epicenter position of the earthquake was confirmed. Then, the maximum deformation quantity at the settlement area was obtained, and the main deformation zone was determined. Finally, using the GIS multiple display function, the deformation results were displayed in the form of statistical tables and sectional and three-dimensional drawings. The deficiencies of the InSAR data were related data post-processing, data explanation, and presentation achievement. Analysis of the InSAR results using GIS effectively compensated for the deficiencies of InSAR. GIS is suitable for extracting information on InSAR deformation fields and can effectively ensure the preciseness of the obtained results, thereby improving research findings in this field.