Investigation of dynamical influence range in shear zone for unclear active fault topography; Example of southern Kyushu

Higa, Saki*; Terusawa, Shuji*; Niwa, Masakazu   ; Shimada, Koji   ; Komatsu, Tetsuya  

In the southern Kyushu shear zone, geological investigation along north-south ca.27 km area near aftershock distributions of the 1997 Kagoshima-ken hokubu earthquake depict striation and sense of shear of small faults. As a result of stress inversion analysis, it was found that the NE-SW compression and NW-SE tension stress fields, consistent with the left-lateral shear of the southern Kyushu shear zone, is localized within central 2 km north-south width zone.