Geochronology and geochemistry of Permian bimodal volcanic rocks from central Inner Mongolia, China: Implications for the late Palaeozoic tectonic evolution of the south-eastern Central Asian Orogenic Belt
The bimodal volcanic rocks in the north-eastern Sonid Zuoqi area erupted at 292–279 Ma. Mafic rocks were derived from metasomatised asthenospheric mantle. Felsic rocks originated from juvenile crustal source. The formation of this bimodal suite in an extensional setting was related to post-collisional delamination.