Seismic Hazard Analysis of Northeast India and its Adjoining Region

In this study, we make an attempt to analyze seismic hazard of the region using probabilistic approach. At the outset peak ground acceleration of the region is determined, then the probability of occurrence of a seismic event greater than 4.0 mb in the next 50 yrs and 100 yrs is estimated and hazard maps are prepared. Next, seismic hazard map of the region for 10% and 30% probability of exceedance respectively in 50 years and 100 years is prepared. Here it has been assumed that the earthquake occurrence follows the Poisson distribution. The pga value is found to vary from 0.15g to 0.51g. The probability of occurrence of at least one event with magnitude >= 4.0mb within the next 50 years and 100 years has been found to vary from 0.48 to 0.96 and 0.71 to 0.99 respectively. This analysis highlighted variations of seismicity in the study region. It has been found that the entire study area does not fall under zone V of seismic hazard map. The region has seismicity varying between zone III and zone V.