The Difference in the Landslide Information by the Difference Between Geographical Features and Geological Conditions

Landslide information, such as the number of landslide occurred by an event and the type of landslide (a deep-seated landslide, a shallow landslide, a debris flow, etc.) are important information for disaster prevention. Because the risk and the damage area change greatly with the number and the type of landslide. To guess the number and the type of landslide in the future decrease the risk and damage. In this research, I investigated and studied the landslide disasters which occurred in the typhoon No. 12 disaster in 2011 and the northern Kyusyu-island heavy rain disaster, in Japan. The result compared with the disasters, area of landslide is larger and number of landslide is fewer in the deep-seated landslide area. In the shallow landslide area, the slope is steeper and the drainage network is more developed. And shallow landslide area mainly consists of volcanic rocks, on the other side deep-seated landslide mainly consists of sedimentary rocks and metamorphic rocks. In deep-seated landslide area, the precipitation type is long-time rain, and in the shallow landslide area is short-time heavy rain. It is surmised that the landslide information are subject to strong influence by geographical features and geological conditions. Therefore, it is important to read and analyze the past landslide disaster hysteresis from geographical feature and geological condition for specifying the landslide information.