Role of supra-subduction zone ophiolites in the tectonic evolution of the southeastern Zagros Orogenic Belt, Iran

Abstract

Ophiolitic rocks in the southeastern part of the Zagros Orogenic Belt can be separated from southwest to northeast, into two groups: the Neyriz ophiolites and the Naien–Shahrebabak–Baft ophiolites. The southeast sector of Sanandaj-Sirjan wasdelimited by the two nearly synchronous ophiolitic belts in its southwestern and northeastern margins. In this study, new ophiolitic formation models were used to explain a viable geodynamic hypothesis on the development of the southeastern Zagros Orogenic Belt. Supra-subduction zone ophiolites have been of particular importance in the reconstruction of regional tectonic evolution andformed near a main subducting oceanic plate. The history of the southeastern Zagros Orogenic Belt is composed of development of two oceanic crusts, referred to as the Neo-Tethys 1 and Neo-Tethys 2. The process of reconstructing of the plate tectonic evolution of the southeastern Zagros Orogenic Belt was proposed on the basis of "Latest Cretaceous-Neogene collision" hypothesis. The supra-subduction zone ophiolites in the southeastern part of the Zagros Orogenic Belt can be classified into "pull related fore-arc Neyriz ophiolites" and "back-arc Naien-Baft ophiolites".