[H-DS08] Landslides and related phenomena

[HDS08-P04] GIS-based cataclinal and anaclinal mapping for slope hazard risk assessment.

Toshimitsu Iwaya¹, *Daisaku Kawabata¹ (1.National Institute of Advanced Industrial Science and Technology)

Keywords:anaclinal, cataclinal, mapping

The geometrical relationship between topographic and bedding planes can be used to infer the cataclinal and anaclinal slope that influence landslide susceptibility. The density and direction of the contour intervals on topographic maps are used to create topographic surfaces. In recent years, the increasing use of DEMs has facilitated the creation of topographic surfaces. On the other hand, it is necessary to read information from the geologic map to create a bedding plane. In geological mapping, stratigraphic boundaries (boundary lines) are created by using contour lines on topographic maps. However, unlike topographic surfaces, formation surfaces are created based on discrete data and must be interpolated from strike and dip information, boundary surfaces, and other information. The method used to create a surface from point and line data is spatial interpolation, but the spatial interpolation method, including the preprocessing process of data processing, is a combination of many detailed conditions and methods. This makes it difficult for novice users and those unfamiliar with GIS to quickly perform the analysis. In this study, a method for creating geometric stratigraphic surfaces using general GIS functions while following geological mapping and reading methods was investigated in the Sasebo area of the northern Kyushu region, and prototype cataclinal and anaclinal maps were created.