Stochastic finite-fault modelling of strong earthquakes in Narmada South Fault, Indian shield

Abstract

The Narmada South Fault in the Indian peninsular shield region is associated with moderate-to-strong earthquakes. The prevailing hazard evidenced by the earthquake-related fatalities in the region imparts significance to the investigations of the seismogenic environment. In the present study, the prevailing seismotectonic conditions specified by parameters associated with source, path and site conditions are appraised. Stochastic finite-fault models are formulated for each scenario earthquake. The simulated peak ground accelerations for the rock sites from the possible mean maximum earthquake of magnitude MW 6.8 goes as high as 0.24 g while fault-rupture of magnitude MW 7.1 exhibits a maximum peak ground acceleration of 0.36 g. The results suggest that present hazard specification of Bureau of Indian Standards as inadequate. The present study is expected to facilitate development of ground motion models for deterministic and probabilistic seismic hazard analysis of the region. © Indian Academy of Sciences.