U-Pb and Re-Os geochronology of the Haolibao porphyry Mo-Cu deposit, NE China: Implications for a Late Permian tectonic setting

摘要

New geochronological data for the Haolibao porphyry Mo-Cu deposit, NE China, yield Permian crystallization zircon U-Pb ages of 278 ± 5 Ma for granite and 267 ± 10 Ma for the granite porphyry that hosts the Mo-Cu mineralization, and four Re-Os molybdenite ages yield an isochron age of 265 ± 3 Ma. These ages disagree with the previous K-Ar age determinations that suggest a correlation of intrusive rocks of the Haolibao area with the Yanshanian intrusive rocks of Cretaceous age. The mineralizations at the Haolibao area may be related to the tectonic-magmatic activity caused by collisional events between the North China Plate and Mongolian terranes during the Permian. The occurrence of the Haolibao plutonic rocks indicates that the Palaeo-Asian-Mongolian Ocean closed during the Permian along the Xilamulun River suture.