The Dahutang tungsten deposit is one of the largest deposits in the Jiangnan tungsten belt. The Jiningian pluton is widely distributed in the orefield, which is considered an ore-bearing wall rock and Ca source for scheelite mineralization. The Jiningian granodiorite samples near ore have high W contents (average 93 ppm). Moreover, their SiO2 and P2O5 contents are positively correlated in Harker diagrams, and the A/CNK values vary between 1.18–1.71, suggesting that the Jiningian granodiorite is high fractionated S-type granites and has the potential for W mineralization. The zircon U-Pb ages of the Jiningian granodiorite samples (17SWD-1, 17SWD-2) are 845 ± 21 Ma (MSWD = 1.7) and 828.7 ± 7.5 Ma (MSWD = 1.0), respectively, representing the formation ages of the Jiningian pluton. The U-Pb age of hydrothermal zircons (~140 Ma) in the Jiningian granodiorite samples is consistent with the mineralization age (150–139 Ma), indicating the strong superimposed modification of the Yanshanian mineralizing fluids. The positive correlation between Ca and W molarity in the Jiningian granodiorite samples demonstrates that they provide considerable Ca and W during Yanshanian mineralization. The W activation migration due to sodium alteration can be inferred from the inverse correlation between Na and W molarity. The study tries to provide a new perspective on the origin of mineralized material in the world-class Dahutang tungsten deposit.

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The formation and evolution of the ancient continental crust are crucial issues in solid-earth geology which are commonly associated with global tectonic events and the formation of economically valuable magmatic-hydrothermal ore deposits. The Cathaysia Block, one of the ancient continents in Southeast Asia, can be subdivided into two parts: the West Cathaysia Block and the East Cathaysia Block. Unlike the East Cathaysia Block, no Precambrian rocks are exposed in the West Cathaysia Block, constraining further understanding of the formation and evolution of this block. In this study, a total of four hundred and thirty-three zircon U-Pb dating analyses and two hundred and eighteen Lu-Hf isotopic analyses on zircon grains from the Jurassic Dengfuxian granites and Ordovician Tanghu granites, Nanling Range, were carried out. LA-ICP-MS zircon U-Pb dating yields mean average 206Pb/238U ages of 152.6 ± 2.2 Ma (MSWD = 1.6) and 442.4 ± 1.7 Ma (MSWD = 3.8), which are regarded as the rock-forming age for the Jurassic Dengfuxian granites and Ordovician Tanghu granites, respectively. The 207Pb/206Pb ages of the inherited zircons from the Jurassic Dengfuxian granites and Ordovician Tanghu granites range from 522 Ma to 3395 Ma, hosting two major peaks at the 0.9–1.0 Ga and 2.4–2.5 Ga. In contrast to the East Cathaysia Block, the West Cathaysia Block lacks the age peak of 1.8–1.9 Ga, indicating that the West Cathaysia Block was not influenced by the assembly of the Columbia supercontinent in the Paleo-Proterozoic. In combination with the Lu-Hf isotopes, we proposed that the crust evolution of the West Cathaysia Block in Archean is dominated by juvenile crustal growth events, and dominated by the crustal reworking since the Proterozoic. The long duration of crustal reworking in the West Cathaysia Block resulted in the enrichment of lithophile elements (e.g., W, Sn, Nb, and Ta) in the crust of that region. Therefore, the Jurassic granites in the Nanling Range, which are mainly derived from the partial melting of Proterozoic basement rocks, became associated with large-scale tungsten polymetallic mineralization.