The crustal assembly of southern Mongolia: New structural, lithological and geochronological data from the Nemegt and Altan ranges

► Nemegt and Altan Nuruu straddle the Dzolen-Edrengin terrane boundary. ► Ophiolite obduction occurred in the late Carboniferous. ► Oroclinal bending, shortening and lateral redistribution occurred in the Permo-Triassic.