Evidence for temporal relationship between the late Mesozoic multistage Qianlishan granite complex and the Shizhuyuan W-Sn-Mo-Bi deposit, SE China.

ABSTRACT

The world-class Shizhuyuan W-Sn-Mo-Bi deposit is spatially related to the Qianlishan granite complex (QGC) in Hunan Province, China. However, the age and classification of the QGC are still debated, and a better understanding of the temporal genetic relationship between the QGC and the Shizhuyuan deposit is essential. Here, we present chemical compositions the intrusive phases of the QGC and the results of detailed zircon U-Pb dating and muscovite Ar-Ar dating of a mineralized greisen vein. Our new zircon laser ablation inductively coupled plasma mass spectrometry U-Pb age data constrain the emplacement of the QGC to 155-151.7 Ma. According to petrological, geochemical and geochronological data and the inferred redox conditions, the QGC can be classified into four phases P1, porphyritic biotite granites; P2, porphyritic biotite granites; P3, equigranular biotite granite; and P4, granite porphyry dikes. All phases, and especially P1-P3, have elevated concentrations of ore-forming metals and heat-producing elements (U, Th, K; volume heat-producing rate of 5.89-14.03 µWm-3), supplying the metal and heat for the metalogic process of the Shizhuyuan deposit. The Ar-Ar muscovite age (154.0 ± 1.6 Ma) of the mineralized greisen vein in the Shizhuyuan deposit is consistent with the emplacement time of the QGC, suggesting their temporal genetic relationship.