[H-DS07] Landslides and related phenomena

[HDS07-22] Extraction and Characterization of Slope Displacement Estimated Areas Based on Interferometric SAR Time Series Analysis in the Shikoku Mountains

*Shintaro Yamasaki¹ (1.Disaster Prevention Research Institute, Kyoto University)

Keywords:Interferometric SAR time series analysi, Landslide, Shikoku mountains, Gravitational slope deformation, Geology

This article presents an example of extracting areas in the Shikoku Mountains where slope movement is estimated to have occurred, based on the nationwide interferometric SAR time-series analysis images (images visualized based on displacement velocity data in the quasi-vertical and quasi-east-west directions) publicly released on the GSI Maps, a web service of the Geospatial Information Authority of Japan, in March 2023, by image interpretation. The estimated gravitational slope deformation areas (EGSDAs) extracted generally correspond to locations where gravitational slope deformation is considered to be occurring. Furthermore, many of them existed in areas of metamorphic accretionary complexes with large elevations and large relative height slopes along actively eroding rivers. On the other hand, it should be noted that there are cases where active slope displacement cannot be detected by interferometric SAR time-series analysis even if they are expected from the topography depending on the shape and orientation of the slope.