Osamu SHIMIZU, Takashi JITOUSONO, Etsuro SHIMOKAWA, Takao YAMAKOSHI, Hiroshi KISA, Shigetaka TAKIGUCHI, Mitsunori SUGIYAMA
Shinmoedake in Kirishima volcano erupted violently on January 26, 2011 and
spewed a large amount of ash over the surrounding area, especially eastward
and southeastward, in the following several days. From the viewpoint of a debris]flow
hazard we examined thickness and grain size of ash deposits, infiltration properties
of tephra]covered slopes, and sediment movement in the upper Takasaki River
basin and the southern area of Takachihonomine after the eruption. On]site tests
for infiltration capacity of the slopes revealed a lower rate in the upper Takasaki
River basin than that of the southern area of Takachihonomine, reflecting thicker
deposits of fine]grained ash in the former basin than that of the latter area.
This is probably the reason why sediment movement in the upper Takasaki River
basin is more active than that of the southern area of Takachihonomine.
od (EDEM)Japan Society of Erosion Control Engineering