Forum Geografi
Vol 36, No 2 (2022): December 2022

Predisposition Factor of Safety of Landslide Dams from Typhoon Talas, Kii Peninsula, Japan

Daikai Rikuto (Graduate School of Oceanology, Sediment Hazards and Disaster Risk Laboratory, Kobe University, 5-1-1 Fukae-minamimachi, Higashinada-ku, Kobe 658-0022, Japan)
Gomez Christopher (Graduate School of Oceanology, Sediment Hazards and Disaster Risk Laboratory, Kobe University, 5-1-1 Fukae-minamimachi, Higashinada-ku, Kobe 658-0022, Japan)
Balazs Bradak (Graduate School of Oceanology, Sediment Hazards and Disaster Risk Laboratory, Kobe University, 5-1-1 Fukae-minamimachi, Higashinada-ku, Kobe 658-0022, Japan)
Aditya Saputra (Faculty of Geography, Universitas Muhammadiyah Surakarta, Jl. A. Yani Tromol Pos 1 Pabelan, Surakarta 57162, Indonesia)
Danang Sri Hadmoko (Faculty of Geography, Universitas Gadjah Mada, Jl. Kaliurang, Sekip Utara, Bulaksumur Sinduadi Sleman, Sendowo, Sinduadi, Kec. Mlati, Kabupaten Sleman, Daerah Istimewa Yogyakarta 55281)



Article Info

Publish Date
29 Dec 2022

Abstract

Landslide dams are less frequent than other landslides, and their very existence is often very-much short-lived, because the temporary dam tends to collapse rapidly. Because of the resulting lack of evidences, there has been less research done on this topic, although the potential catastrophe they can be at the origin of needs assessment. For this purpose, the present contribution aims at differentiating landslides that trigger dams against those that do not inside a group of valleys of the Kii peninsula in Japan, where landslides occurred af-ter the typhoon Talas in 2011. Using topographic map before the event and LiDAR data in its aftermath, the authors have calculated the factor of safety (FS) of different landslides in the same valleys, comparing the da-ta of landslides that created dams against those that did not. The results show that landslides that triggered dams seemed to have a higher FS than those that did not. The authors suggest that it is because larger land-slides are needed and thus appear more stable, but also because at the location where the slopes are stable, the riverbed can incise further instead of growing horizontally, and thus the sediments damming the channel have more chances to block it (as it is narrow) and stop the river from flowing.

Copyrights © 2022






Journal Info

Abbrev

FG

Publisher

Subject

Earth & Planetary Sciences

Description

Forum Geografi, Indonesian Journal of Spatial and Regional Analysis (For. Geo) is an open access, peer-reviewed journal that will consider any original scientific article for expanding the field of geography. The journal publishes articles in both physical and human geography specialties of interest ...