WITNESSES OF THE NEO-TETHYS OCEAN IN SOUTHEAST IRAN: A REVIEW OF THE LATE JURASSIC - CRETACEOUS OPHIOLITES OF THE NORTH MAKRAN DOMAIN

Abstract

This review compiles all available data on the subduction-related and subduction-unrelated ophiolites in the North Makran domain (southeastern Iran) to reconstruct the formation and incorporation of this oceanic lithosphere into the Makran Accretionary Wedge. These data suggest that the evolution was multi-stage, beginning in the Late Jurassic–Early Cretaceous period. During this time, an oceanic lithosphere was formed in a mid-ocean ridge setting, as testified by the Bajgan Complex and the Band-e-Zeyarat ophiolites. Meanwhile, the formation of an intraoceanic subduction zone led to the development of a forearc basin (now represented by the Sorkhband upper mantle sequence) and the subsequent separation of the North Makran Ocean from the main Neo-Tethys. The Late Cretaceous was characterised by magmatism related to within-plate plumes, as evidenced by the Durkan Complex. At the same time, a volcanic arc (now represented by the Ganj Complex) developed due to the subduction of the North Makran Ocean beneath the Lut Block. The final closure of the composite oceanic lithosphere of the North Makran Ocean took place during the latest Cretaceous-Paleocene. The ophiolites of the North Makran domain thus provide a key natural example of how plume activity, ridge processes, plume-ridge interaction, and multiple subductions interacted to generate oceanic lithosphere in a convergent plate margin.