부산대학교 도서관

This paper aims to develop a methodology for understanding the fault activity by observing exposed fault planes without covering younger strata. Based on purpose, faults developed in relatively homogeneous rocks such granitic types are investigated as follows; Gosuke Dam upstream outcrop of Gosukebashi Fault and Funasaka-nishi outcrop of Rokkou Fault were selected for the study of an active fault; and K-3 outcrop of Rokkou Houraikyo Fault was chosen for a non-active fault. The fault planes were examined under the three categories of continuity, cutting of older texture of the fault zone, and smoothness. These three categories were considered according to the following five measurements, with the third being subdivided into three ：（1）continuity ratio; （2）cut ratio of the older existing texture/strata; （3）planarity ratio; （4）roughness/undulation measurement; and （5）arithmetic average roughness obtained from photographic analysis. Of the five measurements, the first three have the potential to discern the threshold between active and non-active faults. Further examination and discussion are required to clarify their applicability as parameters for fault activity evaluation.