Rupture Mechanism of Chamoli Earthquake on 29 March 1999 and its Implications for Seismotectonics of Garhwal Himalaya

Chamoli earthquake of 29 March, 1999 (m_b 6.8) has caused extensive damage to life and property. Macroseismic surveys conducted around Chamoli have indicated maximum intensity of VIII on MSK scale. The epicentral tract of this event is oriented in the E-W direction. The aftershocks for the first few days are concentrated in an area of 40 km x 30 km which is bound by MCT in the north and the Alkananda Fault in the south. The authors have suggested a source model of this event on the basis of data generated as well as the seismotectonic setting of the area and have surmised that this event nucleated at the intersection of a transverse fault and the rupture propagated towards west along the detachment surface.