ELECTRICALLY CONDUCTIVE CRUST IN SOUTHERN TIBET FROM INDEPTH MAGNETOTELLURIC SURVEYING

The crust north of the Himalaya is generally electrically conductive b elow depths of 10 to 20 km, This conductive zone approaches the surfac e beneath the Kangmar dome (dipping north) and extends beneath the Zan gbo suture, A profile crossing the northern Yadong-Gulu rift shows tha t the high conductivity region extends outside the rift, and its top w ithin the rift coincides with a bright spot horizon imaged on the INDE PTH CMP (common midpoint) profiles. The high conductivity of the middl e crust is atypical of stable continental regions and suggests that th ere is a regionally interconnected fluid phase in the crust of the reg ion.