Varying Rate Of Occurrence Of Earthquakes In India And Its Implication On Probabilities Of Occurrence

Abstract

The current research revisits India's seismicity with the goal of investigating the return times of different magnitudes in distinct seismogenic zones in India. India is divided into 24 zones for this reason. The investigation took into account seismicity from prior times until 2020. The Gutenberg Richter magnitude frequency relationship was used to estimate the return times of earthquakes in specific zones. The GRT connection has been computed using several methods that take epistemic uncertainty into account. The a and b parameters are between 1.47 and 7.05 and 0.54 and 1.17, respectively. Zones 17 and 11 have the shortest return periods, indicating strong seismic activity. However, the zones 6 and 12 shows the highest return periods for magnitude 8 which shows that the great magnitude has lowest probability of occurrence in these zones. From earthquake engineering point of view the probabilities of occurrence in next 100, 225, 475, 2475, 50000 and 10000 years have been estimated. The probabilities have been calculated based on the assumptions that the earthquake occurrence follows Poisssonian distribution. It has been observed that the lowest probabilities for 100, 225, 475, 2475, 5000 and 10000 is reported in zones 17. Similarly, the highest probabilities for the return periods 100, 225, 475, 2475, 5000 and 10000 are reported in zones 24. The results are very useful for seismic hazard assessment for the regions.