The Gosukebashi fault zone which is a major active fault in Kinki district, striking NE-SW extends about 15 km along the eastern Rokko Mountains. Detailed geological and geomorphological studies on the southwestern part of the Gosukebashi fault zone were carried out in this study. The following results were obtained.
1) Distinct fault t o pographies showing right-lateral displacement are recognized along the Gosukebashi fault zone.
2) Fault trace l i neaments and fault outcrops show that the fault is a right-lateral strike-slip fault with a reverse displacement component.
3) It was formed that t h e drainages along the fault were dextrally displaced. There is a linear relation of D: aL between the offset (D) and the length (L) of upperstream along the fault.
4) The mean rates of displacement are 1∼4 m/103years in horizontal, an d 0.26∼0.32m/103years in vertical, respectively.
5) Geological and geomorphol o gical studies, such as aerophotograph interpretation and field survey, show that the Gosukebashi fault zone is still active in the Holocene.
