This study combines rainfall records, geological surveys, satellite images, and digital terrain model data to explore the possible factors causing landslides in Shinkai. The geological data surveyed soon after disasters has become invaluable due to a reclamation project in the landslide area. The results show that the landslide area consists of low metamorphic rocks which have been severely schistosed and jointed into wedge-shaped weak planes. When a typhoon brought large quantities and long durations of rainfal, the rock wedges slipped along the weak planes when they were lubricated by water and moved to the Shinkai village, finally leading to large disasters.The causes of landslides in Shinkai are similar to those in Siaolin village, and the landslides happened repeatedly.These findings point to the importance of geological surveys prior to hillside development. development.
Key Words : Typhoon Morakot, dip slope, wedge type failure, Shinkai.