The main aim of the present paper is to study the recurrence pattern of the earthquakes in this region which is highly complex geologically and where many disastrous earthquakes occurred in the past. Among them, Assam earthquakes of 1897 and 1950 and Bihar earthquake of 1934 as located in Fig. I are worth mentioning. The causes of such phenomena presumably lie in the geological and tectonic set up of this region. The study of seismic activity is of paramount importance as it affects the government economy on engineering work at a place.