Studies of Artificial Water Reservoir Triggered Earthquakes at Koyna, India: A Summary

Anthropogenic seismicity has been observed due to filling of artificial water reservoirs, geothermal and natural oil/gas production, and gold/coal mining under favorable geological conditions. Among these, artificial water reservoir triggered seismicity (RTS) is most prominent, with over 200 sites globally where RTS has been observed, including 5 sites where earthquakes exceeding M 6 magnitude occurred. Koyna, located near the west coast of India in stable Deccan Volcanic Province is the most prominent site where the largest RTS event of M 6.3 occurred in 1967, and the RTS has continued till now, for near field study of earthquakes. Here we present a summary of (a) global RTS, (b) scientific work carried in the Koyna region, (c) characterizing RTS, and (d) establishing a 3 km deep Pilot Borehole laboratory as a precursor to setting up of a ∼ 7 km deep bore hole laboratory. The work being carried out is providing necessary inputs for the design of the ∼ 7 km deep borehole laboratory for the near field studies of RTS and shed light on the geneses of earthquakes in general and RTS.