Pure appl. geophys. 153 (1998) 133–149 0033 – 4553/98/010133–17 $ 1.50 +0.20/0 Reservoir-induced Seismicity in China LINYUE CHEN 1 and PRADEEP TALWANI 1 Abstract — A review of case histories of reservoir-induced seismicity (RIS) in China shows that it mainly occurs in granitic and karst terranes. Seismicity in granitic terranes is mainly associated with pore pressure diffusion whereas in karst terranes the chemical effect of water appears to play a major role in triggering RIS. In view of the characteristic features of RIS in China, we can expect moderate earthquakes to be induced by the construction of the Three Gorges Project on the Yangtze River. Key words: Reservoir-induced seismicity in China, mechanism of reservoir-induced seismicity. Introduction Since the earliest, and one of the most destructive cases of reservoir-induced seismicity (RIS), the M s 6.1 earthquake in Xinfengjiang in 1962, there have been 18 other cases of RIS in China. These have ranged in magnitude between M s 4.8 and 2.2, and have occurred in different geologic zones and have been associated with a large range of impoundment histories and water levels. The RIS at these reservoirs has been the subject of non-uniform studies, ranging from detailed studies at Xinfengjiang and Danjiangkou Reservoirs, to very few studies at Shenjiaxia and Shuikou. Very few details are available in English and most accounts are only available in various technical reports, journals and books in Chinese. Two large hydroelectric projects, the Three Gorges Project on the Yangtze River and the Xiaolangdi Project on the Yellow River (Fig. 1) are currently under construction. When completed, they will be among the largest in the world and in view of the incidence of RIS in China, it is important to understand and assess their seismic potential. In order to do so, it is necessary to understand the nature of the RIS that has been observed to date. Towards that end, in this paper we review the lithology of hypocentral areas where RIS has been observed, their filling history and reservoir characteristics. 1 Department of Geological Sciences, University of South Carolina, Columbia, South Carolina, U.S.A.