Quaternary Activity of Huji-Shayang Fault and Seismogenic Structure Relating to Zhongxiang Earthquake

In order to investigate the fault activity and earthquake structure of research area. Field geology, landform survey, fault gouge and terrace dating indicate Huji-shayang fault is characterized by normal faulting and the latest activity time is in late early Pleistocene of Quaternary, approximately 1 136 ka. Furthermore, we make some analysis on relation between regional tectonic stress field and micro-small earthquake activity and fault. Meanwhile, According to field earthquake destroy survey, we draw four earthquake felt area of which size and shape are consistent with strike of the fault. Moreover, we found abnormal phenomenon like fracture and sand-gravel liquefaction in middle Pleistocene reticulate red clay, which suggested a strong shock of magnitude more than 6.0 strike this area of Zhongxiang. Based on these understanding, we discuss the seismogenic structure of Zhongxiang earthquake happening in the year of 1407, 1469, 1603 of magnitude 5.0~5.5. Some conclusion that Hujia-shayang fault controlling Han river garben is possible seismogenic structure of Zhongxiang earthquake can be drawn, which confirm that non-active fault has an ability to produce moderate earthquake in east China.