Abstract
This study has revealed the geological structure of the Sone Hills fault zone and the formation process of the Sone Hills. This fault zone spans the boundary of the Kofu Basin and the Misaka Mountains in Yamanashi Prefecture, which is located in central Japan. Tectonic landforms in the hills run ENE-WSW, and reverse faults, high-angle faults, and normal faults are located along the tectonic landforms. Reverse faults extend between the basin and the hills and between the hills and the mountains. High-angle faults, normal faults, and antithetic (reverse) faults are located at crests and saddles between the reverse faults. In the Sone Hills, faulting resulted in the formation of an anticline with a crest (tectonic bulge) in the Middle Pleistocene. This crest rose further in the Late Pleistocene, forming dissected fans.
