Research of slope collapse by earthquake in active fold zone and landform evolution processes

伊莫河沿岸最古老的阶地的形成年龄被检测到早于16500年前，因为阶地上没有覆盖Asama Kusatsu tephra。根据阶地形成年龄，小松古拉背斜的生长速度估计为0.8-1.9×10^-6/年。这一数值与西山山和欧治亚地区的活动褶皱的增长速度是同一量级。在长野新泻边界地震中，地基灾害主要集中在逆断层的上盘一侧，其分布受地质、地质构造、活动断裂等因素的控制，并指出松山背斜发育与地震有关的可能性。

The age of formation of oldest terrace along Imo River is detected to be younger than 16,500 year ago, because the terrace is not covered with Asama Kusatsu tephra. The growth rate of the Komatsugura anticline is estimated 0.8-1.9 x10^<-6>/year by terrace formation age. This value is same order as the growth rate of active fold in Nishiyama Hills and Ojiya district. In the Nagano Niigata border Earthquake, the foundation disaster was concentrating in the hanging wall side of a reversed fault, in the form governed by distribution of geology, geological structure, and active fault, etc. And it has pointed out a possibility that the Matsunoyama anticline grew in connection with this earthquake.