Electron Spin Resonance Dating of Fault Gouge for Fault Activity in Hangzhou

Electron spin resonance (ESR) dating was widely used in seismic risk assessment. We collected fault gouge samples for ESR dating and sedimentary samples relativing to fault activity for OSL to conclude the last fault movement for Xiaoshan-Qiuchuan Fault trending NE-SW, Changhua-Putuo Fault trending EW-SN and Xiaofeng-Sanmenwan Fault trending NW-SE in Hangzhou, China. However, ESR data were much older than the OSL data of the sediment which was moved by the same fault. It is predicted that ESR data of fault gouge may not represent the age of the last fault movement because of the weak fault activity since late Pleistocene in Hangzhou region, but it still represents the strong fault activity history in Quaternary.