Palaeozoic tectonics and evolutionary history of the Qinling orogen: Evidence from geochemistry and geochronology of ophiolite and related volcanic rocks

► The Danfeng Melange represents remnants of ophiolite and subduction-related rocks. ► Geochemical investigations reveal N-/E- MORB and oceanic island-arc signatures. ► Zircon U-Pb age of 517.8 ± 2.8 Ma constrains formation age of E-MOR gabbros. ► Erlangping ophiolite and related volcanic rocks formed in a back-arc basin setting. ► An Ocean/island-arc/back-arc basin system separated NCB from SCB in Early-Paleozoic.