dc.description.abstract | Typhoon Morakot invading Taiwan on August 8th, 2009 caused numerous major disasters throughout the island. Hsiaolin village located at the foothills of Shiendu Shan on the third day typhoon existence was entirely buried by massive landslide. A detail field investigation focused on structural measurement, around whole the Hsiaolin landslide as well as its surrounding area and the drainage area of the Kaoping River, has been carried out in this study. In order to realize the landslide mechanism of regional settings, we focused on the affect of geological structures and stress analysis around the study area. Wedge failure had been observed at numerous outcrops, which produced by bedding and fault systems’ inter-cutting at the dip-slope area of the mountains. Therefore, in some areas landslide could have happen even in dry season with relative stable condition. After a detailed investigation from Hsiaolin and all other landslides of the Kaoping drainage basin, we came to a conclusion that structure geological setting played a major role as a direct factor for creating the regional landslide. By considering the geometric correlation between geological structure, strata attitude and topography, an objective hazard map can be provided. Besides, based on the slickenside data measured from the fault planes of fresh outcrops, a NW-SE compressional tectonic regime can be reconstructed. Associated with this compression, a conjugated fault system, which is composed of a E-W striking right-lateral fault and a NW-SE striking left-lateral fault, is also expectable in all this area. This fault system caused the slope failure and easy to lead big landslide. The results derived from the structural analysis can also be applied for improving advanced estimations of other related studies.
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