Electrical structure across the Indus Tsangpo suture and Shyok suture zones in NW Himalaya using magnetotelluric studies

Abstract

[1] Magnetotelluric studies in the NW Himalayan region have shown anomalously high conductance of about 20,000 siemens in the crust beneath the Indus Tsangpo suture (ITS) and the adjoining Tso-Morari dome in the depth range of 1–20 km. High heat flow and high attenuation of the seismic waves in the Himalayan crust, together with the observed high conductance indicate presence of wide spread partial melt generated from the subducted Indian crust. The Ladakh batholith appears as a resistive block to the north of ITS. A moderately conductive zone demarcates the Ladakh batholith from Karakoram batholith to the north. The similarity in the resistive structure with the results reported from the Tibetan region by Wei et al. [2001] about 1500 km to the east is rather significant, indicative of a two dimensional nature of the Himalayan collision belt, at least to the first order.