Structural characteristic of a thrust system related gneiss dome of the Zagros hinterland-fold-and-thrust belt: The Sourian and Tutak metamorphic complexes, SW Iran

The Zagros hinterland fold-and-thrust belt left eye-catching features during its evolutionary episodic processes. As such features, the Tutak gneiss dome consists of exhumed middle crust including the Sourian and Tutak metamorphic complexes, which are lied on its edges and core respectively. In spite of several studies were carried out on the two mentioned metamorphic complexes, the structural nature of the dome, not correctly identified, yet. Therefore, the main purpose of this study is to highlight clues about formation mechanism of the Sourian and Tutak metamorphic complexes through structural and microstructural analyses and cross section reconstructions. Based on the fieldwork data, three main deformation phases concordance to the multiphase regional deformation of the Zagros hinterland fold-and-thrust belt, impressed the Sourian and Tutak metamorphic complexes resulted to development of multiple fold generations with interference pattern. According to the constructed cross section and microstructural analyses, it seems that Jim and Sourian major thrusts were controlled the exhumation of the Tutak gneiss dome (thrust-related gneiss dome) along a hybrid channel with producing a duplex thrust system.