Slab break-off and the formation of Permian mafic-ultramafic intrusions in southern margin of Central Asian Orogenic Belt, Xinjiang, NW China

► The basaltic magmas were resulted from melting of asthenosphere and lithospheric mantle. ► The lithospheric mantle had been modified by subduction materials previously. ► Such magmas experienced up to 10% contamination of the Proterozoic metamorphic rocks.