Mesozoic magmatism and metallogenesis associated with the destruction of the North China Craton: Evidence from U–Pb geochronology and stable isotope geochemistry of the Mujicun porphyry Cu–Mo deposit

Abstract

The North China Craton (NCC) provides a classic example of lithospheric destruction and refertilization. The timing and duration of magmatism and related metallogenesis associated with the destruction process are pivotal to understanding the geodynamic controls. In this study, we present zircon U–Pb and Hf data, Re–Os ages, and He, Ar, Pb and S isotope data from the Mujicun porphyry Cu–Mo deposit in the northern Taihang Mountains within the Central Orogenic Belt of the NCC. We constrain the timing of magmatism as 144.1±1.2Ma from zircon U–Pb data on the diorite porphyry that hosts Cu–Mo mineralization. Another U–Pb age of 139.7±1.4Ma was obtained from an epidote skarn that is located in the contact zone between the porphyry and its wall rocks. These data and five Re–Os molybdenite ages that range from 142.7±2.0Ma to 138.5±1.9Ma suggest that magmatism and mineralization occurred in about five million year duration from ~143Ma to ~138Ma. The He, Ar, Pb and, Hf data suggest that magmatism involved recycled Neoarchean lower crustal components, with input of heat and volatiles from an upwelling mantle. The Mujicun porphyry and associated mineralization provide a typical example for magmatism and metallogeny associated with lithospheric thinning in the NCC.