At 1016 hrs a.M. T. Qn July 29, 1970, North &mrn part of ladia coveriDB an area of about 2,80,000 sq. km. in Assam, MeJ;H1aya, Mizoram, A,runachal. Tripura, Manipur, Nagaland, parts of West Bcnaa,t t8J and llariPdcsh. was rocbd, . by an oarth~uake of Richter Magnitude 6.4: AquestionHlrit’ ~ was ul\llertaken immediately after the earthquake for asscssing seismic intensities in MM (1931) ~ ill areas aft’ected by the quake for the purposes of pfCPl9iu ~ ,map .. A macroscismic survey in the’ cpicentral, region was undertaken by Geological Silrwy of Inllia (1970). Maximum intensity approaching VlI WI\S a.ssiJlltld to ,area ,.a~oun,d Mar&.bcri~ and Digboi where some damage to housing proPerty occllrred, No ‘damllP.to ‘.,..cr., bridges and railway track was reported. Distributions of~1I&ko IDteIlsl&ioa.deatIy dOW tbe influence of regional geology and local foundation conditions. .’;~I .~~. runs NE-SW and indicates possible tectonic adjustments along Haflollll’ isSIui& Thrust fault.