Deterministic seismic hazard analysis for greater Mumbai, India.

Abstract

Mumbai City, the financial capital of India is situated on the west coast of the intra-plate continental region of peninsular India (PI), which experienced significant historical earthquakes in the recent past. Seismic hazard analysis for safe and economic design of structures is important for Mumbai for earthquake disaster study and mitigation. Hence, in the present study, deterministic seismic hazard analysis (DSHA) for the Greater Mumbai region (lat. 18.8750N to 19.3250N and long. 72.8250E to 73.1250E with grid spacing 0.050), which includes Mumbai City, Suburban, Thane District, and Navi Mumbai is carried out by using seismicity database of earthquake magnitude MW ≥ 3.5 from 1594 to 2012. The seismic sources are identified from the Seismotectonic Atlas of India within the control region of 300 km radius around Mumbai City (lat. 18.940N, long. 72.840E). The epistemic uncertainty involved in estimation of different input parameters is accounted within a logic tree framework. Final results in terms of spatial variation of 50th and 84th percentile (MCE and SSE) rock level peak horizontal acceleration (PHA) and spectral accelerations (Sa) at short and long periods show high seismic hazards on the southern part of the study region, which can be used for seismic design of structures in the greater Mumbai region.