日本地球惑星科学連合2023年大会

講演情報

[J] 口頭発表

セッション記号 S (固体地球科学) » S-TT 計測技術・研究手法

[S-TT39] 合成開口レーダーとその応用

2023年5月24日(水) 13:45 〜 15:00 304 (幕張メッセ国際会議場)

コンビーナ:阿部 隆博(三重大学大学院生物資源学研究科)、木下 陽平(筑波大学)、姫松 裕志(国立研究開発法人 防災科学技術研究所)、朴 慧美(上智大学地球環境学研究科)、座長:阿部 隆博(三重大学大学院生物資源学研究科)、朴 慧美(上智大学地球環境学研究科)


14:30 〜 14:45

[STT39-09] Unwrapping dense and complex SAR interferograms: Examples from the 2023 Turkey Earthquake

*福島 洋1Okur Yagizalp2,3 (1.東北大学災害科学国際研究所、2.東北大学大学院理学研究科、3.クレルモン・オーベルニュ大学)

キーワード:InSAR、トルコ、地震、位相アンラッピング

Interferometric SAR (InSAR) analysis outputs the displacements in the line-of-sight (LOS) component that occurred during two dates of acquisition. For significant events such as the earthquake occurred along the East Anatolian Fault in the southeastern Turkey in February 2023 (Mw 7.8), the offset tracking analysis and the difference-of-split-band interferograms (DSI) method (Ozawa and Himematsu, 2022) have some advantages compared to the InSAR analysis. Nevertheless, InSAR provides more accurate and higher-resolution results compared to the other two methods. Therefore, there are advantages in using the InSAR results in fault slip inversions or investigating small features.

The difficulty in the cases of aforementioned significant events lies in the phase unwrapping. Specifically, 1) fault ruptures and other secondary fractures in the fault damage zone which results in phase discontinuities, and 2) dense fringes in highly deformed areas are the main challenges.

In this presentation, we will show how the two challenges can be overcome. The problem of phase discontinuities from the faults and fractures can be resolved by an progressive updating of the mask, and the problem of the dense fringes can be resolved by reducing the number of fringes by subtracting the range-offset results or by iterative unwrapping the phase corresponding to the incremental displacements. In this talk, examples from the 2023 Turkey-Syria Earthquake will be given.