Vice Professor YANG Kuifeng and his team investigate the Late Jurassic Linglong and Luanjiahe granites and report zircon U-Pb emplacement ages of 157-159 Ma. Based on detailed petrological, geochronological and geochemical studies on the Late Mesozoic granitic rocks in the northwestern Jiaodong Terrane in the eastern North China Craton (NCC), they attempt to define the magmatic origin and tectonic setting, and to constrain the lithospheric composition and evolution history in the Late Mesozoic.

The Linglong and Luanjiahe granitoids imply the involvement of continental crustal materials from both the eastern NCC and the Yangtze Craton. The Late Jurassic granitoids in the northwestern Jiaodong Terrane suggest that the Linglong and Luanjiahe granitiods were formed under relatively high pressure conditions, and were likely derived from the partial melting of a residual thickened Archean lower crust. The early Cretaceous granodiorites indicate that some mantle components were involved in the magmatic source, and this was possibly triggered by subduction of Pacific Plate beneath the NCC and accompanied by asthenospheric upwelling.

Fig. 1. Schematic map of Mesozoic lithospheric evolution of the Jiaodong Terrane. (Image by YANG)

Yang et al. Reactivation of the Archean lower crust: Implications for zircon geochronology, elemental and Sr–Nd–Hf isotopic geochemistry of late Mesozoic granitoids from northwestern Jiaodong Terrane, the North China Craton. Lithos. 2012, 146-147: 112-127 (Download Here)