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Abstract

The collision of the Arabian and Eurasian plates during the early Miocene resulted in the formation of the Zagros mountain belt, which extends from northwest to southeast across the western half of Iran. This area is of significant geological and tectonic interest due to its complex history and ongoing deformation. Recently, Magnetotelluric (MT) data has been collected along two 400 km profiles in the northern part of the Zagros belt to create the first image of the area's electrical conductivity distribution and to gain insight into how the collision between the two plates is accommodated within the lithosphere and upper asthenosphere. The MT data, measured at 22 long-period sites, was processed using a robust processing technique based on the eigenvalue decomposition method by Egbert (1997) to obtain estimates of the electrical resistivity structure beneath the study area. The phase tensor inversion results indicate the presence of a well-conducting zone at a depth of about 100 km, which may indicate the presence of the asthenosphere. Additionally, the inversion reveals a mid-crustal layer with low resistivity increasing beneath the Arabian plate and probably correlating with the locations of seismic low velocity zones in that region. The result coming from the sites close to the plate’s suture shows complications and is probably biased by 3D phenomena. Therefore, the existing 2D studies will be followed by 3D investigations to obtain a meaningful subsurface model of electrical conductivity.