使用ALOS DInSAR提取汶川地震同震地表形变场

EXTRACTING COSEISMIC DEFORMATION FIELD RELATED TO WENCHUAN Ms8.0 EARTHQUAKE BY USE OF ALOS DInSAR

为探测汶川Ms8.0地震引起的地表形变,用ALOS卫星PALSAR L波段SAR数据与GPS观测数据,采用两轨雷达差分干涉方法,计算出了地震影响区约83 194 km2范围内的同震干涉图与形变场。此外,以16个GPS点的形变数据为参考,对干涉形变的精度进行分析,结果表明:除近断层区域两类数据存在较大差异外,整体吻合程度较高。

In order to detect surface deformation caused by the Wenchuan Ms8.0 earthquake,the two-pass differential interferometric synthetic aperture radar（DInSAR） method is employed for analyzing the ground displacement due to the main shock by using both the ALOS satellite PALSAR L-band SAR data and GPS data.We computed the coseismic interferogram and the deformation field with spatial resolution of 15 m in an area of about 83 194 km 2.Moreover,the accuracy of deformation values derived interferometrically is evaluated by taking the GPS measurements at 16 sites as the reference data.The results show that the two types of measurements are in good agreement,except that there exist remarkable discrepancy in the near-fault areas.