Seismicity of Odisha ( an Eastern State of Indian Peninsula ) : A Comprehensive Deterministic Seismic Hazard Study

Odisha, an eastern state of India, is highly regarded as the centre for culture. The economy of the state is growing steadily through mining, steel plants, infrastructure development by smart city plans etc. Indian standard code for seismic design (IS-1893: 2016) considers the entire state under two seismic zone as zone II and III with generalized PGA values for the entire state. This consideration may underestimate the seismic hazard at various places in the state. The code prescribed zone map is very generalised representation which does not consider detailed regional tectonic features in and around the state. Hence it is required to develop the regional seismic hazard map considering the effects of the tectonic feature present in and around the region. For the present study region, a total of 38 faults were identified. The maximum magnitude is assigned to all these faults using regional fault rupture characterization. Ground motion model developed by the national disaster management authority was used and it was found that out of 38, only 8 faults were found to be affecting the seismicity of the state. The peak ground acceleration and the spectral acceleration values were determined for all the district places for rock type sites. These seismicity parameters were compared with the values recommended by the Indian Standard code so that these values can be used to estimate earthquake load and design the earthquake resistant structure in Odisha state.