1985 年 22 巻 3 号 p. 1-10
Topography and geology of the midstream area of the Hime valley is fairly complicated, and there are abundant groundwater caused by heavy snowfalls of this area.
There can be seen many gently slanting surfaces in the arrea; the writers investigated these gentle slopes topographycally, geologically and genetically.
The sloping surfaces are classified into 1) old erosion surface 2) slope caused by landslip of pyroclastics 3) slope caused by Tertiary landslide 4) fluvial terrace and so on Therefore, many of them have some relation to landslide in broad sense.
The gentle slopes of Tertiary landslide are concentrated in areas of alternated mudstone and sandstone, and they are closely related to geologic structure. The writers reexamined the genesis of many gentle slopes along the Hime river which have been considered to be fluvial terraces so far. The study on gentle slanting surface in landslide area will be effective for both prediction and counter measure of landslide.