Basement Configuration from Magnetotelluric Studies in Bhuj Earthquake Epicentral Zone, Gujarat, India

摘要

A wide band (1000 - 0.001 Hz) magnetotelluric study has been taken up in the Bhuj earthquake epicentral zone and 21 sites have been occupied along three profiles during March-April 2001 to understand the deep structure of the region. In addition the region surrounding Bhuj has been probed earlier with number of MT profiles and the subsurface structure is well constrained from hydrocarbon exploration point of view besides seismotectonic studies. In the present study, the results obtained along 130 km long profile from Mundra to Rapar oriented in NE-SW direction passing through the epicenter are presented considering these two databases. The subsurface structure has shown interesting correlation with the surface deformations, a new basement configuration and associated seismotectonics of the region. Our main result is relating the basement configuration and surface ruptures.