3:30 PM - 4:45 PM
[HDS05-P08] Effects of active fault types on earthquake-induced deep-seated landslides
Keywords:deep-seated landslides, earthquake, reverse fault, strike-slip fault, hanging wall, foot wall
As is known in the earthquake engineering field (e.g., Sato and Hirata, 2000, KAGAKU, vol. 70, No.1, 58-65, in Japanese), the damage caused by a strike-slip fault earthquake is more concentrated in a narrower range around the fault compared with the case by a reverse fault. A similar phenomenon was also confirmed for DSLs in this study. Many recent cases demonstrate that many DSLs occur in the hanging wall because the hanging wall suffers larger seismic motion than the foot wall by reverse fault earthquakes (e.g., Has Baator et al., 2010, JSECE annual meeting abstract, No. 57, 48-49, in Japanese). A similar result was also observed for the historical events. The discussion above suggests that, in addition to the distance to the nearest active fault of a potential landslide, we should take account of types of the active fault (reverse/strike-slip/normal) and whether the landslide is located in hanging or foot wall to assess the occurrence of earthquake-induced DSLs. The popular attenuation model (Si and Midorikawa, 1999, Journal of Struct. Construct. Eng., No. 523, 63-70, in Japanese) of peak ground velocity (PGV) that is commonly used for the building assessment is also required for similar considerations when used for the landslide assessment.