Jamei, SusanGhorbani, MansourWilliams, IanMoayyed, Mohsen2022-06-070020-6814http://hdl.handle.net/1885/267174The Late Palaeozoic rock associations, in particular A-type igneous rocks, of Iran are rarely exposed, but they are key to reconstructing the evolutionary history of the Tethyan oceans. Zircon U–Pb dating of a representative rhyolite sample from Pir-Eshagh, NW Iran, yields an Early Carboniferous (Visean) crystallization age of 340 ± 2.7 Ma. The extrusive rhyolite has the chemical characteristics of the A1 subtype of A-type magmas, providing evidence for a magmatic activity within extensional basin. The composition of rocks is metaluminous to slightly peraluminous and K-rich, with trace element signatures ‎similar to those of OIB. Low Y/Nb and Ce/Nb ratios are consistent with a combination of source enrichment and crustal contamination and ultimately that the studied rhyolites have formed by fractional crystallization from an enriched mantle-derived mafic parental magma, with ‎crustal interactions. Palaeogeographic reconstructions of the Tethyan oceans and their borders imply that the Proto-Tethys Ocean has not spread in Iranian plate, although evidence for Paleo-Tethys and Neo-Tethys in the form of ophiolitic units is well-preserved. The Late Palaeozoic magmatic rocks of Iran define a trend parallel to ‎the ridge separating Neo-Tethys the Iranian plate from Arabia and demonstrate that the ‎separation of the Cimmerian terranes from northern Gondwana by the opening of the Neo-Tethys Ocean, and their drift northwards, began ‎in the Late Devonian to Early Carboniferous.application/pdfen-AU© 2020 Informa UK Limited, trading as Taylor & Francis GroupProto-Tethys-Paleo-TethysNeo-TethysIran-Pir-Eshagh rhyolite202010.1080/00206814.2020.17684432021-01-17