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[Display omitted] • Hongqiling Sn-W polymetallic deposit is a product of granitic magmatism in Late Jurassic. • The elemental composition of primary cassiterite is controlled by the compositions of ore-forming fluid and the rate of crystallization. Hongqiling deposit is one of the most typical hydrothermal vein type Sn-W polymetallic deposits in the Dongpo ore field, southern Hunan. It is an ideal object to study the Sn-W mineralization in the Nanling metallogenic belt and even in the whole South China Block, and to reveal the regional metallogenetic regularity. Based on the detailed investigation of the deposit geology, this paper discusses the mineralization age and processes of the Hongqiling hydrothermal vein type Sn-W polymetallic deposit by LA-MC-ICP-MS in-situ U-Pb dating and trace element geochemistry of cassiterite from the quartz vein type Sn-W ore body. Cathodoluminescence (CL) imaging shows that cassiterite in Hongqiling deposit can be divided into two generations. primary cassiterite (Cst-I) and altered cassiterite (Cst-II). The LA-MC-ICP-MS in-situ U-Pb age of the two groups of Cst-I samples are 158.9 ± 0.7 Ma and 158.4 ± 0.8 Ma, respectively, which are well consistent with the mineralization ages of most Sn-W deposits in the Nanling metallogenic belt, and are also consistent with the ages of middle to late Jurassic magmatic activity represented by the Qianlishan intrusion. This indicates that the Hongqiling deposit, like many Sn-W deposits in the Nanling metallogenic belt, is genetically related to the regional Middle to Late Jurassic granitic magmatic activities. LA-ICP-MS trace element analysis shows that trace elements such as Na and Cs are mainly distributed in fluid inclusions in cassiterite, while the major elements such as Mg, Al, and Si are mainly distributed in the mineral inclusions, and other elements such as W, U, Zr, Hf and Ti are mainly distributed in the cassiterite by isomorphic substitution. The high Fe and W contents in both primary and altered cassiterite indicate that the ore-forming fluid of Hongqiling deposit is mainly derived from granitic magma. The fluctuating variation of Fe, V, Sc, Ti, Zr, Hf, Nb and Ta in the primary cassiterite with the crystalline bands indicates that there are two large-scale pulses of magmatic hydrothermal fluid during the mineralization process, while the altered cassiterite is relatively depleted of Ti, Sc, Zr and U elements, and enriched in Pb which may represent the compositional characteristics of the late-stage fluid. In summary, the Hongqiling hydrothermal vein type Sn-W polymetallic deposit was formed by the pulsating exsolution of magmatic hydrothermal fluid of late Jurassic granitic magmatism. The trace elemental compositions of primary cassiterite are generally controlled by the compositions of ore-forming fluid and the rate of crystallization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Yield the age of rutile and sericite to determine the absolute age of mineralization in gold deposits is feasible. • Hydrothermal rutile and sericite paragenesis with native gold are identified from auriferous quartz veins. • New U-Pb rutile and Rb-Sr sericite geochronology confirm multistage gold mineralization in the Liling goldfield. The Liling goldfield located in northeastern (NE) Hunan contains >200 tons of proven gold reserves. The gold mineralization age in Liling has long been controversial due to the lack of datable minerals. In this study, petrographic observations indicate that hydrothermal rutile and sericite were precipitated with auriferous pyrite/arsenopyrite in the ore veins. The electron probe microanalysis (EPMA) results show that the sericite from ores and the sericite from Neoproterozoic slate display distinct compositions (Especially Al, K, and Ti). The high W (1,081–36,456 ppm) and low Zr (21.35–288.7 ppm) contents of the rutile suggests a hydrothermal origin. We reported new laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) U-Pb ages of ore-stage hydrothermal rutile (415.2 ± 8.3 Ma) for the Tuanshanbei gold deposit, and sericite Rb-Sr ages (417.6 ± 12.9 Ma and 216.9 ± 7.8 Ma) for the Tuanshanbei and Yanlinsi gold deposits in the goldfield. The new data confirm that multistage gold mineralization has occurred in the Liling goldfield, and falls within the generally accepted timing (ca. 430–400 Ma and 250–200 Ma) of gold mineralization in the Jiangnan Orogen. Integration of geological characteristics, tectonic setting, and geochronology of the Liling goldfield suggest two Au mineralization episodes, which occurred in the Late Silurian-Early Devonian intracontinental orogeny and Triassic intracontinental orogeny, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three stages of W-Sn mineralization in the Xitian Ore Field have been identified. • Triassic skarn-type mineralization occurred in a relatively closed metallogenic system. • Jurassic quartz vein-type mineralization occurred in an open system with addition of meteoric water. • Deeply buried Early Cretaceous magmatic-hydrothermal deposits may exist in the Xitian Ore Field. • Evolution from skarn-type to vein-type mineralization was related to tectonic environment changing. The Nanling Metallogenic Belt is a major W-Sn province in South China containing numerous ore deposits formed during a complex history of magma emplacement and mineralization. The Xitian ore field in Hunan Province is a typical example of a late magmatic-metallogenic system. In this study, garnets from skarn-type ores in the Xitian ore field yield a U-Pb age of 231.7 ± 1.3 Ma (n = 33), whereas cassiterite grains from quartz vein-type ores give U-Pb ages of 158 to 154 Ma (n = 72) and 140.7 ± 3.3 Ma (n = 6), suggesting three stages of W-Sn mineralization (Late Triassic, Late Jurassic, and Early Cretaceous). In the Late Triassic skarn-type ores, the REE patterns of scheelite change from MREE-enriched to LREE-enriched with time, whereas the REE patterns of scheelite shift from MREE-enriched to MREE-depleted in the Late Jurassic quartz vein-type ores, indicating diverse metallogenic processes. Differences in the Y/Ho ratios and Sr-O isotope compositions of scheelite further confirm discrete metallogenic pathways for the Late Triassic skarn-type W ore and the Late Jurassic quartz vein-type ore, with fluid-rock interaction of the former dominated by magmatic-hydrothermal fluids whereas the latter was influenced by large amounts of meteoric water. A model emphasizing the evolution from skarn-type to vein-type metallogeny is proposed to account for the complex genesis of multistage W–Sn deposits related to the Xitian granite complex. More generally, this study demonstrates that in-situ LA-ICP(MC)-MS U-Pb dating and isotopic analysis of hydrothermal minerals are powerful tools to decipher the nature, timing, and evolution of multistage W-Sn metallogenic systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • The three mineralization stages including cassiterite-sulfide, Pb-Zn-Sb sulfide, and carbonate were identified. • The trace element compositions of the fluid inclusions in different stages indicate that the ore-forming fluids probably originated from the same evolving granitic magma. • Sn-depleted but Pb-Zn-rich fluids interacted with Sb from the Sb-rich Cambrian sequence and leached it to create Sb-rich fluids. Tin (Sn) and antimony (Sb) deposits commonly formed in distinctive environments and thus the coexisting of Sn and Sb mineralization in a single deposit is rarely recognized worldwide and the genesis of this type of deposit remains poorly understood. The newly discovered Sanshiliuwan Sn-Pb-Zn-Sb deposit in the Xianghualing ore district of Southern Hunan has metal reserves of 44,000 t Sn, 291,000 t Pb + Zn, and 20,000 t Sb and average grades of 0.39 % Sn, 4.91 % Pb + Zn, and 1.00 % Sb, and thus offers an ideal window for prospecting the genesis of the Sn-Pb-Zn-Sb deposit. The orebodies in the deposit were mainly hosted in Cambrian and Devonian sequences and occurred as veins. Three mineralization stages were recognized including the cassiterite-sulfide, Pb-Zn-Sb sulfide, and carbonate. The fluid inclusions in the quartz from the cassiterite-sulfide stage (QtzI) have homogenization temperatures of 418–244 °C (typically 400–320 °C) and salinities in the range of 0.87–10.11 % NaCl equiv. While the fluid inclusions in the quartz from the Pb-Zn-Sb sulfide stage (QtzII) have the homogenization temperatures of 253–141 °C (typically 250–180 °C) and salinities in the range of 0.18–9.86 % NaCl equiv. The fluid inclusions in quartz from different mineralization stages have low Na+/K+ ratios in the range of 0.05–0.96 and clustered Cs/Rb ratios of 2–5, indicating that the ore fluids of the deposit were likely to have been exsolved exclusively from a magmatic source. Cassiterite U-Pb dating suggested that the Sanshiliuwan deposit formed ca. 155 Ma, which is well coincided with the concealed granites (formed ca. 156 Ma). Therefore, the genetic model for this deposit would demonstrate that evolved fluids from Jurassic granites invaded the faults and deposited Sn and Sn-Pb-Zn ore veins in the granite periphery. Thence, Sn-depleted but Pb-Zn-rich fluids interacted with the Sb-rich Cambrian sequence and leached it to create Sb-rich fluids. In response to fluid cooling and boiling, Pb-Zn-Sb-rich fluids then deposited Pb-Zn-Sb sulfide ore veins at favorable structural sites. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ca. 150–120 Ma was also an important mineralization period in South China. • The low oxygen fugacity may be responsible for little or no Cu resources in the Dayunshan-Mufushan region. • The ca. 150–120 Ma mineralization was likely caused by Middle Jurassic to Early Cretaceous extension. The Jiangnan Orogen is located between the Yangtze and Cathaysia blocks, and hosts abundant Au, Sb, W, Cu, Pb, Zn, Ag, and Ta-Nb-(Li-Be) deposits. Among these, both the Taolin and Lishan Pb-Zn-(Cu) polymetallic deposits in northeastern Hunan Province are large Pb-Zn deposits, which are located at the northwestern and southern margins of the Late Jurassic to Early Cretaceous Dayunshan-Mufushan composite pluton, respectively. However, the mineralization ages of these deposits remain controversial and poorly constrained. In this study, muscovite 40Ar/39Ar dating of the Taolin and Lishan deposits along with zircon U-Pb dating and geochemical analysis of the Dayunshan-Mufushan composite pluton were undertaken to constrain the age and nature of the Late Jurassic to Early Cretaceous magmatism and related mineralization in South China. Zircon U-Pb dating of the biotite monzogranite and two-mica monzogranite yielded emplacement ages of ca. 149 and 145–136 Ma, respectively. Muscovite from the ore-bearing granitic pegmatites in both the Taolin and Lishan deposits yielded well-defined 40Ar/39Ar ages of ca. 121 and 129 Ma, respectively. These results and previously published data indicate that the Dayunshan-Mufushan composite pluton was emplaced in several stages at ca. 154–148, 146–137, and 136–127 Ma, and experienced associated, multi-stage, granitic pegmatite magmatism at ca. 142, 131, and 125–120 Ma. Two mineralization events occurred at ca. 141–136 and 133–120 Ma in the Pb-Zn-(Cu-Co-Mo), Ta-Nb-Li-Be, and Au deposits in northeastern Hunan Province, including the Dayunshan-Mufushan region. Zircons from the Dayunshan-Mufushan composite pluton record low oxygen fugacity (ƒO 2) conditions, indicating the pluton was likely responsible for the large-scale Pb-Zn mineralization. In addition to the 170–160, 160–150, and 120–80 Ma mineralization events, the Late Jurassic to Early Cretaceous (ca. 150–120 Ma) was also an important period of mineralization in South China. This mineralization was likely initiated by Middle Jurassic to Early Cretaceous extension associated with subduction, subsequent slab rollback, and possible break-off of the Paleo-Pacific plate, which led to lithospheric collapse and thinning. [ABSTRACT FROM AUTHOR]

[Display omitted] • Yield the age of rutile to determine the absolute age of mineralization in gold deposits is feasible. • Hydrothermal rutile from auriferous quartz veins can represent the age of gold mineralization of Hengjiangchong deposit. • U-Pb isotope analysis of rutile indicates a significant gold mineralization event during Caledonian in northeast of Hunan province of Jiangnan Orogen. The Jiangnan Orogen is a well-known gold belt in China with a large number of gold deposits. The Jiangnan Orogen has complex geological history, and most gold deposits have not been well dated. Consequently, the regional timing of gold mineralization is still controversial. The Hengjiangchong is a representative gold deposit in the orogen. In this study, syn -ore hydrothermal rutile in quartz-polymetallic sulfides-gold-calcite veins was dated by LA-ICP-MS, yielding a Tera-Wasserburg lower intercept U-Pb date of 416.1 ± 7.3 Ma (2σ, n = 26, MSWD = 2.4). This date represents the age of gold mineralization at Hengjiangchong, and falls within the generally accepted timing of gold mineralization in the Jiangnan Orogen (ca. 425–400 Ma). Combined with the regional kinematics, gold mineralization likely occurred during the extension associated with the Yangtze-Cathaysia post-collisional deformation in the Siluro-Devonian intracontinental orogen. This also indicates that the late Silurian was a major gold mineralization epoch in the Jiangnan Orogen, challenging to some previous claims that late Silurian hydrothermal veins are largely ore barren. [ABSTRACT FROM AUTHOR]

[Display omitted] • LA-ICP-MS monazites analysis confirms the emplacement of two-mica monzogranites occurred in ∼ 221.7–218.2 Ma. • W mineralization in Zanshi shows accordant mineralization age of ∼ 218.7–215.1 Ma. • A new Late Triassic W mineralization and magmatism are recognized. • the cooling rate of the ore-forming hydrothermal system may be a key controlling factor of ore grade. The Nanling metallogenic belt is rich in critical metal minerals, e.g., tungsten, tin, and rare earth element (REE). The newly discovered Zanshi tungsten deposit, located at the northeastern part of the Nanling metallogenic belt, has drawn great attention from geologists for its rare Triassic magmatic-hydrothermal event in this region. Based on detailed field work, a series of geochemical and geochronological analyses, including whole-rock geochemical analyses consisting of major and trace elements, LA-ICP-MS monazite U-Pb dating of the granites and quartz Rb-Sr and muscovite 40Ar-39Ar isotopic dating of the ore-bearing quartz veins, were carried out in this study, aiming to constrain the rock- and ore-forming ages of the deposit as well as the petrogenesis of granites. The whole-rock geochemical analyses, the medium to fine-grained two-mica monzonitic granites in the Zanshi tungsten deposit are peraluminous S-type granites and derived from the partial melting of metamorphic graywackes in a post-collisional extensional tectonic setting. The LA-ICP-MS monazite U-Pb dating on the two medium- to fine-grained two-mica monzonitic granite samples yields weighted average ages of 218.2 ± 1.2 Ma (MSWD = 1.3) and 221.7 ± 1.7 Ma (MSWD = 2.7), respectively. These ages are consistent with the quartz Rb-Sr and muscovite 40Ar-39Ar isotopic ages of the ore-bearing quartz veins, which are 218.7 ± 3.2 Ma and 215.1 ± 2.0 Ma, respectively, revealing that the tungsten mineralization in this deposit is related to the Triassic magmatic-hydrothermal activity. Combined with previous studies, the Zanshi tungsten deposit likely experienced about 5 M.y. of magmatic evolution and 3.6 M.y. of mineralization. Meanwhile, the cooling rate of the ore-forming fluids of this deposit was about 111 °C/M.y., which may be regarded as a controlling factor which affects the ore grade of the deposit. [ABSTRACT FROM AUTHOR]