マス・ムーブメントの第四紀地質学的考察  [in Japanese] Mass movement from the Viewpoint of Quaternary Geology  [in Japanese]

1. Most of mass movement disasters such as slope failure and landslide in Japan show the fall down or movement of the surface deposits covering the bed rocks in the slope of mountains. These deposits comprise wethered soil, talus cone deposits and landslide debris etc, For the prediction of mass movements, I would like to emphasize the importance of Quaternary geologic studies on the surface deposits mentioned above. 2. In this paper, some examples concerning mass movement history during Quaternary era are presented. 3. Present active landslides in Japan have occurred with in the paleo-landslide areas which are covered by the paleo-landslide debris. Therefore, Quaternary geologic map is very important as the basic data for making hazard map of landslide. 4. Many large scale slope failures have occurred from secondary fall of paleo-talus cone deposits. To know the distribution of such deposits is necessary for recognition of hazardus slope areas.