Seismic recurrence parameters for India and adjoined regions

Journal of Seismology

K P Sreejaya, S. T. G. Raghukanth, & J Dhanya

2022-06-16

This article focuses on estimating the seismic recurrence parameters of India and adjoining regions based on a comprehensive catalogue assimilated from various sources. The study region encompasses latitude 0∘ N–40∘ N and longitude 65∘ E–100∘ E. The updated catalogue for the region contained 69519 events, including 28770 mainshocks. The updated catalogue was employed in the estimation of recurrence characteristics of the region. Here, zonal and spatial smoothening-based approaches were employed to estimate seismicity characteristics on a grid of 0.1∘×0.1∘. The active regions like the Himalayas, North-Eastern India, Andaman, and Koyna-Warna regions were observed to have relatively lesser b values indicating the occurrence of larger magnitude events and higher values for activity rate N(4), indicating a more frequent occurrence of an earthquake. The reported values can be further used in seismic hazard estimations for the region