A Late Cretaceous tin metallogenic event in Nanling W-Sn metallogenic province: Constraints from U-Pb, Ar-Ar geochronology at the Jiepailing Sn-Be-F deposit, Hunan, China

摘要

The Jiepailing deposit, located in southern Hunan Province, China, is a giant Sn-Be-F deposit in the Nanling W-Sn province. The Sn-Be-F mineralization is spatially associated with the Jiepailing granite porphyry. LA-MC-ICP-MS zircon U-Pb dating of the Jiepailing granite porphyry yielded a weighted mean Pb-206/U-238 age of 905 +/- 0.9 Ma (MSWD = 0.32), which is interpreted as the emplacement age of the granite porphyry. Hydrothermal muscovite yields a plateau Ar-40/Ar-39 age of 92.1 +/- 0.7 Ma (MSWD = 0.9), which is well consistent with the zircon U-Pb age of the Jiepailing granite porphyry responsible for the Sn-Be-F mineralization, indicating a temporal link between the emplacement of the Jiepailing granite porphyry and the Sn-Be-F mineralization. Our new high precise geochronological data suggest that the Jiepailing giant Sn-Be-F deposit and related granite formed during the early Late Cretaceous (92-90 Ma), which provided convincing evidence for a previously unrecognized metallogenic event related to Late Cretaceous granitic magmatism in Nanling region. The occurrence of the Late Cretaceous Sn metallogenic event identified in southern Hunan Province further highlights the importance of systematic metallogenic studies of the Nanling W-Sn province. Integrated with high precise geochronological data obtained previously, it is suggested that the Nanling region mainly experienced three tectonomagmatic activities and lithospheric thinning events during Mesozoic, which are responsible for three Sn-W metallogenic events to form the world-class Nanling W-Sn metallogenic province. (C) 2014 Elsevier B.V. All rights reserved.