Abstract
This paper presents the detailed seismic hazard assessment of the peninsular India (lat. 8-28N and long. 67.5-90E) which is considered to be seismically most stable landmasses of the Indian plate. Past seismic history in this region (Koyna, 10 December 1967; Bhadrachalam, 13 April 1969; Broach, 23 March 1970; Hyderabad, 30 June 1983; Latur, 30 September 1993; Jabalpur, 22 May 1997; Bhuj, 26 January 2001 etc) clearly shows that the seismicity of the area is varying. There were more than five damaging earthquakes with magnitudes greater than Mw 6.0 have occurred in this region, stressing the importance of detailed seismic hazard assessment for the region. For India, Bhatia et al. (1999) published a probabilistic seismic hazard map based on several well identified and prominent source zones in the country. An attempt has been made in this paper to study the present seismic status of this region incorporating the seismicity, tectonic and geological characteristics and using the collected earthquake data Peak Ground Acceleration was estimated using the attenuation relation developed by Iyengar and Raghukanth (2004). Estimated PGA values were used to compute the deviation with respect to assigned PGA values for various regions provided in Indian Standard code IS 1893:2002. The results show that, the estimated PGA in many areas of the Peninsular India is more than the specified value in the current seismic macrozonation map of the country. This provides an important basis for attempting the detailed microzonation of an area within the Penisular India. Key words: Seismic hazard, Peak ground acceleration (PGA), Peninsular India, Seismiczonation