On the seismic hazard in the Koyna region Maharastra, India

Gumbel's extreme value theory has been applied to estimate the probability of occurrence and return period of the largest earthquakes in Koyna region India.The statistical model of Epstein and Lornnitz (1966) is discussed with reference to the Gumbel's extreme value theory.The expected extremes based on 21-years (1964-1984) seisnicity data of six-monthly extreme values of earthquakes for the region have been ploted.The mean line of expected extreme (LEE) is drawn to study the mean return periods of the largest possible earthquakes with their probability of occurrence. The yearly expected number,mean return period and earthquake risk have been estimated.The most probable medium size earthquakes that may occur in the region are predicted.The results presented in this study are only best long-term estimates subject to the limitation of the data.