Evolution of the crust and upper mantle structure in Northern Tibetan Plateau from INDEPTH magnetotelluric data

were re-analyzed and re-modelled in preparation for the MT Phase IV of the project focusing on the northern margins of the Tibetan plateau. Although, in general, the dominant features are the same as the prior models, the new models are geometrically more complex exhibiting greater lateral variability. The South Kunlun Fault (SKF) can be identified as a boundary between a conductive middle crust weakened by partial melt, and a dry and cold resistive crust north of the fault, and can be reasonably concluded to be a rheological boundary. The mid-crustal conductive features exhibit an interesting correlation with the surface thrusting of the northern Tibetan plateau, implying structural control of the conductivity distribution. This correlation raises an interesting issue concerning the time relation between the tectonic features of the area and partial melt, which we will explore with the new data