1 College of Earth Sciences, Jilin University, Changchun 130061, China; 2 Ninth Branch, Geological Survey of Jilin Province, Changchun 130102, China; 3 Pingmei Shenma Jiangong Group Co?? Ltd??, Pingdingshan 467000, Henan, China; 4 College of Geography Sciences, Harbin Normal University, Harbin 150025, China; 5 State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Changchun 130012, China

The micro?morphological characteristics of quartz grains isolated from fault gouge samples collected in the Yangshulin profile of Shuiquanzigou -Tianshankou fault zone were studied by scanning electron microscopy(SEM). The micro - morphological types of quartz grains were identified, classified and statistically analyzed to estimate the relative time of fault activity. Meanwhile, the activity mode of the fault was identified by fuzzy mathematical method. The results show that fault activity began in the Early Pleistocene and experienced many stages of activity until the Holocene. According to the lateral tendency of the age of fault activity from new to old, it is inferred that the hanging wall of the fault was the main moving side, and the development direction of fault gouge was from the footwall to hanging wall. The movement mode of fault was mainly stick?slip, and the creep - slip was weak, it was an active fault related to earthquake.