Extracting faults inactive since the Late Pleistocene from fault catalogues in Japan for investigation on fault fracture zone properties related to fault activity

Abstract

For faults without overlaying Quaternary sediments where conventional basic methods such as geomorphology survey and excavation of trenches cannot be applied to obtain the paleoseismic data for seismic hazard assessment, the physical and chemical features of exhumed fault fracture zones developed in basement rocks may provide valuable clues to infer the seismic activity. We conducted literature survey on faults which cuts granite basement and have been inactive since the Late Pleistocene in order to compare the properties of the fault fracture zones to those of well-known active faults and establish the feasibility of paleoseismic investigation for basement faults. Through the cross-check mainly using three literature sources, the survey extracted only three faults (southern part of the Futaba fault, the Chimata fault and the Uchihata fault system) from more than 4200 faults in Japan including duplicate ones. The three faults features relatively low seismicity along them and the difference of fault type from the surrounding active faults.