Advancement of technology for predicting future topographic changes due to river denudation

Kawamura, Makoto*; Nishiyama, Nariaki  ; Jia, H.*; Ishikawa, Taiki*; Koizumi, Yukiko*

In safety assessments of geological disposal, it is necessary to consider changes in the surface relief of flat areas such as coastal areas over the next tens of thousands of years, including changes in the formation process and hydrological conditions of the geological environment due to river incision and other factors. One tool that has been developed to examine this issue is the "Topography and Disposal Site Depth Change Analysis Tool" (Yamaguchi et al., 2020). However, it is important to evaluate the validity of topography change predictions made using this tool by comparing them with the actual topography. In this study, the validity of the simulation results was evaluated by comparing the cross-sectional and longitudinal profiles of virtual rivers created by numerical simulation using this tool with those of actual rivers in Japan.