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[Display omitted] • Zircon U-Pb dating results refine the emplacement age of the Xikeng pluton at 232.2 ± 1.1 Ma. • Cassiterite and wolframite U-Pb dating constrains the timing of W-Sn mineralization from Xigkeng deposit at 228.4 ± 0.90 Ma and 227.8 ± 1.60 Ma, respectively. • Source of magmatic materials was derived from reworking of crustal materials under an extensional setting. The Chongyi–Shangyou–Dayu ore-concentrated district represents one of the most important wolframite production bases in China, and most of the W-Sn deposits formed in the early Yanshanian period. The Xikeng quartz vein-type W-Sn deposit is located spatially not far from the Triassic Keshuling granitic pluton. The deposit contains 43 ore-bearing quartz veins, in which the ore minerals are mainly cassiterite and wolframite. These ore veins are concentrated in the Sinian metasandstone and sandy slate of the Laohutang Formation and extend down to the top of the concealed granite. The concealed intrusion is composed of medium- to fine-grained muscovite granites, which relate to the Indosinian Keshuling granite, according to geophysical data. Zircon grains from the concealed Xikeng granitic intrusion have a concordant U-Pb age of 232.1 ± 1.1 Ma (MSWD = 0.9). The zircon εHf(t) values range from −11.0 to −7.9, indicating primary reworking of the ancient crustal materials. Wolframite and cassiterite grains yield Tera-Wasserburg concordia intercept ages of 228.4 ± 0.9 Ma (MSWD = 1.2) and 227.8 ± 1.6 Ma (MSWD = 0.3) for the Xikeng deposit, respectively. These data demonstrate that the Indosinian W-Sn mineralization events were genetically related to granitic magma activities that share similar magmatic sources with the Yanshanian W-Sn mineralization-associated granitic intrusions. Combined with previous robust granitic and metallogenic ages, this paper identifies a new Indosinian W-Sn mineralization event in southern Jiangxi Province, Nanling Range. [ABSTRACT FROM AUTHOR]

• The Sinongduo deposit is the first discovered low-sulfidation epithermal deposit. • The Pb-Zn mineralization is mainly concentrated in the range of 60.9–63.7 Ma. The Sinongduo Ag-Pb-Zn deposit is the first documented low-sulfidation epithermal deposit in Tibet and located on the southern side of the Longge'er-Gongbujiangda arc fault belt of the Lhasa terrane. The Ag-rich base metal veins and relatively low-grade breccias and stockworks in the Sinongduo deposit occur in the Paleocene high-potassium calc-alkaline to shoshonitic series volcanic rocks, including rhyolitic welded tuff breccia and volcanic breccia, rhyolitic ignimbrite, rhyolitic crystal fragment tufflava, rhyolite, and rhyolitic tuff. A nearly N-S-trending fault is the most important ore-controlling structure in the deposit. Galena and sphalerite are the dominant ore minerals in quartz-sericite-illite ± adularia veins, with subordinate argentite, pyrargyrite, native silver, chalcopyrite, pyrite and tennantite. The most widespread silver minerals are argentite, pyrargyrite, pearceite and native silver, which occur in fissures in Fe-Mn carbonates, jasper and early sulfides. The mineralization process can be divided into a pre-ore stage, main ore stage, and post-ore stage, and the main metallogenic stage is divided into the galena substage, sphalerite substage and silver minerals substage. Microthermometric analyses of the primary liquid-rich and vapour-rich fluid inclusions (FIs) in the sphalerite (SpII), main ore stage quartz (QzII) and post-ore stage quartz (QzIII) of the Sinongduo deposit indicate that the FIs in SpII, QzII and QzIII are mainly homogenized at temperatures of 197.2–280.8 °C, 185.6–290.4 °C and 148.2–218.7 °C with salinities of 1.40–5.71 wt% NaCl equiv., 1.59–5.71 wt% NaCl equiv. and 2.07–8.94 wt% NaCl equiv., respectively. These data indicate that the deposit was formed in a low-temperature and low-salinity environment, corroborating an epithermal system of mineralization. The O and H isotope compositions of the ore-forming fluids (δ18O = −0.6 to −6.3‰; δD = −177 to −151‰) indicate there was a major contribution from a meteoric water component to metallogenesis. All of the Pb isotope data from the metal sulfides and country rocks in the Sinongduo deposit in this study are similar and imply a close genetic relationship. The δ34S values of galena and sphalerite exhibit narrow distributions, ranging from +4.1‰ to +5.6‰ and from +7.6‰ to +8.4‰ respectively, with average values of +5.0‰ and +8.1‰, respectively, suggesting a uniform source. The Ar-Ar ages determined from sericite in the quartz-sericite-illite-sulfide veins range from 60.9 ± 0.7 to 63.1 ± 0.7 Ma, showing that the timing of epithermal Ag-Pb-Zn mineralization in the study area is consistent with the eruption of the Dianzhong Formation volcanic rocks (DVR) (U-Pb dating, 65–62 Ma), which indicates a genetic relationship. The characteristics of FIs, the H-O-S-Pb isotope data and the mineralization ages suggest that the ore-forming fluids were primarily sourced from circulating meteoric water, while S and Pb were derived from the DVR. Our results, combined with previous data on the regional geology, ore geology, FIs, and tectonic setting, indicate that the Sinongduo Ag-Pb-Zn deposit was produced in an epithermal system that formed on the southern side of the Longge'er-Gongbujiangda fault-block uplift belt, following the northward subduction of the Neo-Tethyan oceanic plate beneath the Asian continent. [ABSTRACT FROM AUTHOR]

The Jiama copper deposit is one of the largest deposits recently found in Tibet and is composed of three types of mineralization including skarn, hornfels and porphyry. To investigate the relationship between mineralization, structure and alteration, we report new zircon U-Pb age and present field observations on the deformation characteritics associated with the copper mineralization in Jiama. Two main periods of deformation were identified, represented by D1 and D2 in Jiama. The first deformation ( D1) occurred around 50 Ma, whereas the second deformation ( D2) that was closely related to mineralization occurred later. Previous zircon U-Pb and molybnite Re-Os dating results indicate that the mineralizatoin occurred at ∼15 Ma and thus the D1 regional deformation significantly occurred before the mineralization time, although the D1 deformation probably provided important space for the development of significant copper deposition. Our new mapping and observations on the D2 deformation demonstrate that the mineralization was closely coeval with or slightly later than the time of D2 deformation. The new U-Pb zircon age further indicates that the aplite formed in ∼17.0 Ma and thus the D2 deformation happened later than this time because the D2 deformation cut across the aplite, which is proposed to be the key control for copper mineralization. Altered laminated hornfels including three types of alteration ( A-, K- and S-type) were found spatially associated with the D2 deformation. The type- A is mainly silicification, with fine sericite or chlorite, as well as abundant disseminated sulphides on fracture surfaces; the type- S is mainly fine-grained silicification with patches of chlorite, epidote and common sulphides; the type- K (potassic alteration) appears to be fine-grained biotite. Such types of alteration indicate the presence of skarns at depth where ore shoots are located. Taken together, the multiple structural-magmatic-mineralization events contributed to the formation of the supergiant Jiama porphyry copper deposit in Tibet. The results have general implication for regional exploration. [ABSTRACT FROM AUTHOR]

The article discusses a study that focuses on the minerals, geological alteration and fluid basics of the first high sulfidation epithermal-porphyry copper-gold deposits in Tibet, China. Topics discussed include discovery of some new copper-sulfur and copper-iron-sulfur minerals; role of temperature and salinity in fluid inclusions and mixing of meteoricwater and porphyry fluid to form deposits in low temperature and salinity.

In order to understand how the metallogenic process of porphyry deposit specifically and directly respond to regional uplifting and exhumation, we compiled previous fluid inclusion data of 32 porphyry deposits in China by recalculating the fluid trapping depths and trapping depth reduction magnitude from early to late mineralization stage veins. The data reveal that the average trapping pressure ratio (Ave TPE/TPL) between early‐ and late‐stage veins of the these deposits are 1.2–18.4, mainly in the range of 1.35–5.83, with average trapping pressure reduction (1–Ave TPL/TPE) from early‐ to late‐ stage veins are 17%–95%, and mainly in the range of 25%–83%. The fluid trapping pressure based mineralization depths most of the porphyry deposits in China had decreased from early to late vein stages by at least 450 m (900–5800 m predominant), or greater than 950 m when take the average depth reduction value, which is greater than the current gap between early‐ and late‐ stage veins of each deposit. We propose that the apparently greater mineralization depth reduction magnitude than the current elevation gaps between early and late veins are likely a consequence of syn‐mineralization uplifting and exhumation process that often occurs in porphyry systems. [ABSTRACT FROM AUTHOR]

The article offers information on the geochemical features and prospecting development of Southern Tiegelong Giant Epithermal Copper Deposit in Tibet, China. Topics discussed include types of metallic sulphides ores detected by energy spectroscopy scanning; metallogenic stages of mineralization such as sedimentary diagenesis and hydrothermal mineralization; and formation of deposits in Early Cretaceous era.

The article discusses the research study conducted that examines the genetic types of mineral deposits of Xiongcun District in Gangdese porphyry copper belt in Tibet, People's Republic of China (PRC). It mentions the genesis of the Gangdese deposit as epithermal, porphyry, and porphyry-epithermal deposit. It further mentions that the deposit is characterized by developed pyrrhotite and ilmenite, that have similar mineral assemblages to the reduced porphyry copper-gold deposit (RPCDs).

The article presents brief information on the geological characteristics of Xiachahe aluminum deposit at Zhenyuan, in Yunnan, China. Topics discussed include geological overview of mineral deposit in the north western region of the Ailaoshan golden belt in China, brief information on the characteristics of mineral orebody and ores, and impact of mineral alternation on the gathering and mineralization of the gold.

The article discusses mineralization and metallogenic process of the orogenic gold deposits in Ailaoshan, Yunnan, China. Topics include types of genesis of orogenic deposits including hydrothermal, metamorphic hydrothermal and simultaneous sedimentation, Ailaoshan metallogenic belt undergoing three major geological processes including hyperplasia orogeny, collision orogeny and superposition, and characteristic of Ailaoshan tectonic style.

• Gradients in white mica wavelength are associated with specific rock units. • White mica wavelength is corresponding with geochemical results. • The clusters of white mica wavelength show the stages of mineralization. • The middle and longer wavelength of white mica are implication for exploration. Field measurement of the short-wave infrared (SWIR) reflectance from drill hole samples proved to be an effective method to map variations in white mica composition (Tschermak substitution) associated with hydrothermal alteration zonation of the Jiama porphyry-skarn Cu deposit, Tibetan Plateau, China. This SWIR mineral spectral information provides geological insights into: (a) the possible nature of the related magmatic intrusions. (b) the physicochemistry of the associated hydrothermal fluids; (c) the interactions between these fluids and country rocks; and (d) potential vectors to economic mineralization. The results suggest that the Al-OH band wavelength of white mica can used as an indicator in the subsequent steps of prospecting. [ABSTRACT FROM AUTHOR]

The Duolong area is the most important part of the Western Bangong-Nujiang Suture Zone porphyry Cu(Au) metallogenic belt, in Tibet, China. Here new detailed data are presented from LA-ICP-MS zircon U-Pb, whole-rock geochemical, and in-situ zircon Hf isotope analyses for igneous rocks in the large Naruo deposit (2.51 Mt of Cu and 82 t of Au) which is located ∼2 km NE of the Duolong (Duobuza and Bolong) super-large gold-rich porphyry copper deposit. We integrated our results with previous research of other porphyry deposits in the Duolong area and have identified the timing, geodynamic setting, and petrogenesis of the mineralization-associated magmatic events. Based on the measurements, the Duolong area porphyry Cu(Au) deposit formations are associated with Early Cretaceous intermediate-felsic magmatism, which is consistent with U-Pb zircon ages of 120 Ma. All the main intrusive rocks in the ore-concentrated area have similar lithogeochemical characteristics; they show a relative enrichment in both light rare earth elements (LREEs) and large-ion lithophile elements (LILEs: Rb, Ba, K, etc.) and relative depletion in both heavy rare earth elements (HREEs) and high field strength elements (HFSEs: Nb, Ta, Zr, Hf, etc.). Moreover, the granite porphyry shows positive εHf( t) values between 1.38-7.37 suggesting that magmas were potentially derived from the partial melting of a depleted mantle wedge that had been metasomatized by subducted slab-derived fluids or melts. This paper points out that the formation of the porphyry-epithermal Cu(Au) deposit in the Duolong area was dominated by northward subduction of the Bangongco Tethys Plate beneath the Qiangtang block in the Early Cretaceous (124-114 Ma), when the subducted oceanic crust reached 50-70 km underground and generated different degrees of phase transformation, which lead to a melt produced by dehydration of amphibole minerals, a metasomatized mantle wedge, and induced mantle partial melting that produced the magma. Those deposits occurred in a continental arc tectonic setting, which is similar to the continental margin arc environment of the ocean-continent subduction setting of the Andes metallogenic belt in South America. [ABSTRACT FROM AUTHOR]

The Tiegelongnan deposit is a newly discovered super-large porphyry-epithermal Cu-(Au) deposit in the western part of the Bangong Co-Nujiang metallogenic belt, Tibet (China). Field geology and geochronology indicate that the porphyry mineralization was closely related to the Early Cretaceous intermediate-felsic intrusions (ca. 123-120 Ma). Various epithermal ore and gangue mineral types were discovered in the middle-shallow part of the orebody, indicating the presence of epithermal mineralization at Tiegelongnan. Potassic, propylitic, phyllic and advanced argillic alteration zones were identified. 40Ar/39Ar dating of hydrothermal biotite (potassic zone), sericite (phyllic zone), and alunite (advanced argillic zone) in/around the ore-bearing granodiorite porphyry yielded 121.1±0.6 Ma (1σ), 120.8±0.7 Ma (1σ) and 117.9±1.6 Ma (1σ), respectively. Five hydrothermal mineralization stages were identified, of which the Stage IV pyrite was Rb-Sr dated to be 117.5±1.8 Ma (2σ), representing the end of epithermal mineralization. Field geology and geochronology suggest that both the epithermal and porphyry mineralization belong to the same magmatic-hydrothermal system. The Tiegelongnan super-large Cu-(Au) deposit may have undergone a prolonged magmatic-hydrothermal evolution, with the major mineralization event occurring at ca.120-117Ma. [ABSTRACT FROM AUTHOR]

The article presents a study to determine geological importance of rhenium (Re)-osmium (Os) isotopic dating of molybdenites in the Galale skarn copper (Cu)-gold (Au) deposit in Tibet, China. Topics discussed include determination of the age of granodiorite by using the laser ablation-inductively coupled plasma-mass spectrometry, isochron ages of Re-Os testing, and galale deposit and gaerqiong deposit resulting from magma-mineralization.

Copper resources in China are rich, but imported copper products are still required. Researches on metallogenic regularity of major types of copper deposits by geologists have involved in worldwide classification, significant copper belts, representative copper deposits, etc. Studies on metallogenic regularity of copper deposits in China also have made achievements with a long-term work. Combined with latest exploration advances obtained in recent ten years, this review aims to conclude the achievements of researches on copper metallogenic regularity in China. Based on data of 814 copper deposits and other ore (mineralized) occurrences, ten prediction types of copper deposits have been suggested. Porphyry and skarn copper ores are taken as the key targets. Porphyry copper deposits are the most important one which concentrate in Gangdese, Changdu-Sanjiang, Dexing and East Tianshan. The Cenozoic and Mesozoic are the major metallogenic epochs. Four main metallogenic epochs are been studied based on the copper ore geochronological data including Precambrian Era (Archean and Proterozoic), Paleozoic Era, Mesozoic Era and Cenozoic Era. Based on the study of metallogenic series of ore deposits in China, twenty-seven metallogenic series of copper deposits are proposed. This is suggested to deepen the study of metallogenic regularity of copper ore and provide the theory guide for copper resources prediction in China. [ABSTRACT FROM AUTHOR]