D-InSAR技术在长白山天池火山形变 监测中的误差分析与应用

选取长白山天池火山区15景JERS-1 L波段SAR存档数据,利用二轨法进行SAR差分干涉处理.最终用4景JERS-1数据获取了覆盖相似时间段的3幅D-InSAR形变图,提取了研究区1994~1998年的地表形变场.研究表明:远离天池火山的平坦区域形变微弱;从天池火山的山脚向上到2000~2200 m高程处,表现为逐渐增强的隆升形变,最高形变速率达到LOS(视线向)5 mm/a.尽管没有同期地面实测资料验证,但研究结论与2002~2005年的一等水准测量结果及地震活动性具有定性的一致性;与Kim的同期InSAR研究具有定量的可比性.在时间上向前延伸了对长白山天池火山的形变监测时段,为研究长白山天池火山活动状态提供了更多的形变信息.

Deformation monitoring of Changbaishan Tianchi volcano using D-InSAR technique and error analysis

In this study we applied two-pass D-InSAR technique to process 15 JERS-1 SAR data. The final deformation field of Changbaishan Tianchi volcano from 1994 to 1998 was expressed in 3 displacement maps which were obtained from 4 JERS-1 SAR data. The stuty achieves the following: firstly, the flat region far away from the summit of Changbaishan Tianchi volcano shows no obvious deformation; secondly, there is an increasing upward deformation from the foot of the mountain up to the areas at the elevation about 2000~2200 m, and the maximum uplift rate is 5 mm/a. Although the estimated inflation rate is not confirmed due to the lack of field work data, the results accord with the leveling studies from 2002 to 2005 and the seismic activity between 1994 and 1998. In addition, the largest deformation rate of 5mm/a is close to the result of Kim's study who also applied InSAR technique using several SAR data acquired in the same period. This study extends the deformation monitoring period of Changbaishan Tianchi volcano for several years, and provides more displacement information for future studies.