Thermal regime of the lower crust in the eastern Khondalite Belt, North China Craton, constrained by Zr-in-rutile thermometry mapping

Ultrahigh temperature (UHT) metamorphism represents the thermally extreme metamorphic conditions in mid- to lower crust, and its generation is significant for our understanding of crustal differentiation crust-mantle interaction. Several Paleoproterozoic UHT localities have been reported from eastern Khondalite Belt, North China Craton. However, precise spatial scale that was affected by this still unknown, therefore mechanism generate broadly debated. Zr-in-rutile thermometry regarded as a valid tool estimate near-peak granulites. Here we establish thermal regime crust Belt using large-scale (∼10,000 km2) mapping. Thirty-eight rutile-bearing garnet-sillimanite gneisses were collected, rutile far zircon lacks ilmenite reaction rims selected electron probe microanalysis. Results show size at least 3000 km2. rocks closely correspond with charnockites, small exposed mafic imply not caused intrusion magma. likely developed during post-collisional extension which anomalous heat reflects both radiogenic heating an overthickened orogen additionally elevated mantle flux due subsequent lithosphere asthenosphere upwelling. Nearly all terranes formed prior ∼550 Ma, but their drivers are probably simply same.