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The granites associated with world–class W and Sn deposits generally have high concentrations of U, Th, and K and can be classified as high heat producing (HHP) granites (>5 μW m−3) because of high radiogenic heat production, but how long radiogenic heat can prolong the suprasolidus lifetime of magmas and whether radiogenic heat exerts an impact on W and Sn mineralization is poorly understood. To answer these questions, finite element numerical modeling was established to link magma cooling by heat conduction with diffusion of W, Sn, and H 2 O from silicate melts to coexisting aqueous fluids before the solidus is reached. The magma in the models is emplaced to a depth of 5 km and its size (vertical thickness of 4–5 km and horizontal length of 20 km) is constrained by the granites associated with world–class W and Sn deposits. Fluid convection was not considered in the models. The sensitivity analysis and comparison results suggest that the suprasolidus lifetimes of HHP magmas are positively correlated with the heat production and magma thickness and negatively correlated with the solidus temperatures and the thermal conductivity of host rocks. Average radiogenic heat of 5–10 μW m−3, together with decreased solidus temperatures due to magmatic differentiation and a moderate thermal conductivity of host rocks, can prolong the suprasolidus lifetime of HHP magmas by 49–427 ka (1 Ma = 1000 ka), corresponding to 11–85% of the suprasolidus lifetime of equally sized magmas with normal radiogenic heat (2 μW m−3). From the available gravity modeling data, over half of the granites associated with world–class W and Sn deposits are at least 1 km thicker than the values calculated from the empirical power–law equation, and the modeling results indicate that an increase of 500–1000 m in magma thickness prolongs the suprasolidus lifetimes of HHP magmas (5 μW m−3) by 50–74%. During magma cooling before solidus is reached, the diffusion of W and Sn is at least several orders of magnitude slower than that of H 2 O in hydrous melts; thus, the equilibrium partitioning of these two metals between silicate melts and coexisting aqueous fluids is not reached, and the metal diffusion from melts is a rate-limiting step. The prolongation of the suprasolidus lifetimes by radiogenic heat and decreased solidus temperatures can allow extraction of 17–95% more W and Sn from silicate melts before the solidus is reached and increase the possibility of producing W and Sn mineralization at later stages. Therefore, the coexistence of HHP granites and world–class W and Sn deposits is not accidental. [ABSTRACT FROM AUTHOR]

The Shizhuyuan ore field has three mineralized zones around the Qianlishan granite complex with a radius of ~6 km: W-Sn-Mo-Bi (inner zone), Pb-Zn (middle zone), and Hg-Sb (outer zone). However, whether Pb-Zn and Hg-Sb mineralization is genetically related to the Qianlishan granites is still debated. Here, we conducted in situ pyrite trace element analysis to study the combinations and distributions. The Bi concentration gradually decreases from the inner zone to the outer zone, while the Mn and Sb contents show the opposite trend. Pyrites from each zone are distributed in distinct zones in the binary plot of Co/Ni-Bi, which is an effective discrimination diagram indicating the degree of hydrothermal alteration. Collectively, the gradual changes in pyrite trace element characteristics among the three ore-forming zones provide evidence to indicate that these zones probably compose a whole magmatic-hydrothermal system associated with the Qianlishan granite complex. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The contribution of the mantle to the formation of granites with mantle‐like or juvenile crustal properties having positive εHf(t) and εNd(t) values remains ambiguous. We have carried out petrologic, geochemical, and zircon U–Pb–Hf–O isotope composition analyses on the Woniuhe and Yuantoupiao granites and associated enclaves with such properties in the northern and southern Lesser Xing'an Range, NE China to determine the crust–mantle interactions involved in the petrogenesis of these host granites and enclaves. The two host granites and their enclaves have identical crystallization ages of ~180–175 Ma within analytical error. The petrological, mineral microstructural, geochronological, Hf–O isotopic, and whole‐rock geochemical data imply that mixing between felsic and mafic magmas occurred in both the Woniuhe and Yuantoupiao plutons. The primary magmas of the enclaves in the two plutons most likely are both mantle‐derived. Hence, mantle materials were directly involved in the genesis of both the Woniuhe and Yuantoupiao host granites through the emplacement of mantle magmas. Combined with the published petro‐geochemical data, our data indicate that large‐scale underplating and emplacement of mantle magmas following crustal growth can occur and may be responsible for the magmatism in the region in the Early Jurassic. This underplating and emplacement might be related to the subduction of the oceanic plate between the Songliao and Jiamusi Massifs beneath the former. [ABSTRACT FROM AUTHOR]

The Cuihongshan deposit is a giant Fe‐polymetallic skarn deposit located in the northern zone of the Lesser Xing'an–Zhangguangcai Range (LXZR), NE China. It is predominantly hosted in skarn contact zones between marble and alkali‐feldspar granites and monzogranites, with minor in fracture zones of granodiorites. Because of dense vegetation cover, complex intrusions, and contact relation between orebodies and rocks, the metallogenesis of the deposit is poorly understood. Here, we present detailed whole‐rock geochemistry, zircon U–Pb geochronology of granitoids, and molybdenite Re–Os isotopic dating data. All of the granitoids in the Cuihongshan deposit area are silica and potassium rich, highly fractionated, showing affinities to high‐fractionated I‐type granites. However, compared with the other granitoids, the Late Triassic alkali‐feldspar granites have higher differentiation index, stronger enrichment in F, W, Mo, Pb, Th, U, and volatiles with partial mineralization. The zircon U–Pb dating of the granodiorite, monzogranite, and alkali‐feldspar granite yielded weighted average ages of 493 ± 4, 194 ± 1, and 204 ± 1 Ma, respectively. The Re–Os dating of molybdenites from the Cuibei and Cuizhong ore sections yielded isochron ages of 205 ± 2 and 204 ± 4 Ma, respectively, which are consistent with the emplacement age of the alkali‐feldspar granite. Combined with the lines of evidence from the contact relationship between the orebodies and alkali‐feldspar granite, the disseminated mineralization and the enrichment in ore‐forming elements and volatiles in the alkali‐feldspar granite, these indicate that the Late Triassic alkali‐feldspar granite rather than the monzogranite as previously reported, has a close genetic relationship with the Cuihongshan deposit. In addition, the alkali‐feldspar granites occur as apophyses and dikes, but the Late Cambrian and Early Jurassic granitoids occur as batholiths. This indicates that, according to the theory that "small intrusions form large deposits", a potential Late Triassic (~204 Ma) buried batholith might have provided abundant ore‐forming materials. However, the top parts of the Late Cambrian and Early Jurassic granitoids have been denudated, which is unfavourable for significant deposit preservation and mineralization related to the 2 stages of granitoids. This study gives a significant suggestion that exposed, and blind apophyses and dikes should be further considered in the exploration and study of metal deposits in NE China. Three phases of mineralization occurred in the LXZR in the Triassic–Jurassic, namely, porphyry–skarn Cu–Mo polymetallic mineralization (~250–240 Ma), skarn Fe–Pb–Zn polymetallic mineralization (~204–190 Ma), and porphyry Mo polymetallic mineralization (~180–160 Ma). On the basis of regional data, the LXZR experienced subduction and collisional settings during ~260–185 Ma and ~180–160 Ma, respectively. Hence, the Early Triassic (~250–240 Ma) and Late Triassic–Early Jurassic (~204–190 Ma) mineralizations represented by the Baoshan and Cuihongshan deposits, respectively, are related to the early and late subduction of the oceanic plate between the Songliao and Jiamusi massifs beneath the Songliao Massif, respectively. This also indicates a potential mineralization in the LXZR in the Middle Triassic. However, the genesis of the late large‐scale porphyry Mo polymetallic deposits (~185–160 Ma; e.g., Daheishan, Luming, Huojihe, Xinghualong, Xingshan, and Wulugetushan deposits) is constrained by the collision of the Songliao and Jiamusi massifs. [ABSTRACT FROM AUTHOR]

Xiaoqinling District is an important gold-producing area in China. It ranks second to Jiaodong with regard to gold deposits. The uprising period of the Wenyu granitic pluton and the wall-rocks of the deposit, as well as the mineralizing depth and reserved place of gold ore bodies, are significant to ore exploration. Fission-track (FT) analysis of zircons and apatites of granitic rocks from the Wenyu granitic pluton shows that apatite FT (AFT) data modeling indicates a rapid cooling rate of 20°C/Ma from 138 to 120 Ma after emplacement at 138 Ma. Thermal evolution and inversion curves suggest a secondary phase of fast cooling and uprising from 45 to 35 Ma, and 35 Ma, respectively, with a cooling rate of 6.7°C/Ma and a denudation quantity of ∼4.3 km. The last cooling phase took place from <4 Ma, with an average cooling rate of ∼11.3°C/Ma and a denudation amount of 1.3 km. Total exhumation quantity of 5.6 km and uprising elevation of 7.3 km are similar to the estimated results of fluid inclusions from the Dongtongyu and Wenyu gold deposits. The 39Ar/ 40Ar dating of sericite from the fault planes of the Xunmadao-Xiaohe and Taiyao faults demonstrate two uprising activities of the ore-host metamorphic complex. The Huashan and Wenyu granitic plutons intensively occurred during 77 and 45 Ma, respectively. These data sets are valuable for understanding the uplifting process and for preserving gold ore bodies in the Xiaoqinling area, as well as for further studies on tectonic evolutions of the Taihua Complex and the Qinling-Dabie Orogen. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Qianlishan granite complex last for 38.8–57.4 Ma. • The duration of the QGC has positive correlation with the volumetric heat production. • Mineralization events well accord with the protracted hydrothermal lifespan. The Dongpo ore field, containing a series of W-Sn-Mo-Bi-Pb-Zn granite-related deposits, is a typical reduced intrusion-related system centered with the causative zoned Qianlishan granite complex (QGC). The QGC comprises porphyritic granite, equigranular granite and granite porphyry. According to zircon U-Pb age data, the emplacement timing of the QGC was constrained to 155–151.7 Ma. Here, we conducted a set of geochronological analyses with different closure temperatures (including monazite, apatite U-Pb, biotite and muscovite Ar-Ar and zircon fission track dating) on the QGC, revealing that the QGC experienced a protracted magmatic-hydrothermal timespan of 38.8–53.8 my. The protracted lifespan is probably due to radiogenic heat supplied by highly enriched high-heat-producing elements. The mineralizing blossom time (149–154.2 Ma) in the Dongpo ore field is in accordance with the prolonged lifespan (5.7 my: from 149.3 Ma to 155 Ma) of the magmatic-hydrothermal process caused by the QGC over the temperature range of 300–800 °C. This result implies that successive inputs of magma with high heat-producing elements (U, Th, K) play a fundamental role in the metal enrichment process of intrusion-related deposits and the formation of large economic ore fields. [ABSTRACT FROM AUTHOR]