In north bank of the Kinokawa River, there are Median Tectonic Line, Mikabu tectonic line and Hongu fault are running from east to west restrictively. Median Tectonic Line is the longest fault line in Japan and divide the West Japan into Inner zone and Outer zone, and Mikabu tectonic line is located almost along the Aridagawa River, and Hongu fault are running from Minabe to the southern part of Hatenashi mountain range. The geology is divided into three parts almost equally by these fault lines as Paleozoic, Mesozoic and Cenozoic from north and distributed on belt condition.
In these areas, landslide zone is strongly regulated by geologic tectonic line and mainly located along the Median Tectonic Line and Sanbagawa River metamorphic belt and Paleogene zone. Sites susceptible to landsliding are mainly underlain by sedimentary rock and metamorphic crystalline schist rock. |
