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The Shimensi tungsten polymetallic deposit, situated in the Dahutang ore field, South China, is one of the largest tungsten deposits in the world, with an estimated WO3 reserve of 0.74 million tons. Coarse-grained porphyritic biotite granite (CPBG), fine-grained porphyritic biotite granite (FPBG), fine-grained biotite granite (FBG) and biotite granite porphyry (BGP) are all ore-related, but their diagenetic relationships and contributions to W-Cu-Mo mineralization are still in dispute. LA-ICP-MS monazite U-Pb dating of the CPBG, FPBG, FBG and BGP yield emplacement ages of 147.9 ± 1.1 Ma, 146.4 ± 1.1 Ma, 138.6 ± 0.98 Ma and 142.8 ± 1.7 Ma, respectively. Whole-rock geochemical results indicate that the four granites should be classified as S-type granites, but BGP has distinct features transitional between S- and I-type granites. They were possibly generated by partial melting of upper crustal pelites and basic volcanic rocks with different proportion from the Neoproterozoic Shuangqiaoshan Group in the source. Proportional variation in the magmatic source (clay and basic basalts) induces the change of geochemical compositions of the Shimensi granites. Geochemical characteristics suggest that they were derived from two magma chambers (the CPBG, FPBG and FBG vs. the BGP) and experienced different evolutionary processes and different degree of magmatic differentiation during magmatic evolution. Chondrite-normalized REE patterns for the four granites display low total REE contents, variable and strongly enriched LREE relative to HREE and medium-strong negative Eu anomalies. They are enriched in Rb, Th, U, Ta and depleted in Ba, Nb, Sr, P, Ti. Biotites are iron-rich and aluminum-poor, and can be classified as ferro-biotite (CPBG, FPBG and FBG) and siderophyllite (BGP). The partial melting of tungsten-rich metasediments of the Shuangqiaoshan Group and high degree of fractional crystallization led to enrichment in tungsten in the magma suites. Oxygen fugacities of the CPBG a

The investigation of epigenetic carbonate-hosted Pb-Zn deposits from China and Europe in the Eastern and Western orogens of the Tethyan Domain, have provided a new perspective on the range of processes operating in this deposit class globally. However, improved metallogenic models require new constraints on the timing of mineralization throughout the Domain. To address this need, we applied Re-Os pyrite dating to the world class Irankuh Zn-Pb deposit, Iran. The Irankah deposit is located in the thrust belt of the Malayer-Esfahan Pb-Zn Metallogenic Belt (MEMB) in the Zagros Orogen, Iran. Mineralization is hosted by the Goushfil Main Fault and adjacent dolomitized limestones. The hydrothermal mineral assemblage comprises sphalerite, galena, pyrite, minor chalcopyrite and sulfosalt minerals, together with dolomite, barite and abundant quartz. Pyrite associated with main-stage sphalerite mineralization has low concentrations of 3 to 37 ng/g Re and 6 to 49 pg/g Os that are typical of low-level highly radiogenic (LLHR) sulfides. Nonetheless, vein and replacement pyrites from the Goushfil orebody yielded a 5-point isochron age of 66.5 ± 1.6 Ma that is interpreted as the main Zn-Pb mineralization age. The new mineralization age confirms an epigenetic origin for the Irankuh Zn-Pb deposit and supports an early onset for compressional deformation in the Zagros Orogen. The geochronological data support textural evidence that mineralization in veins occurred during regional compression in an active tectonic environment. Therefore the possibility that magmatic fluids and/or heat contributed to the mineralizing system should be incorporated into regional exploration models. Further work is required to test the extent to which epigenetic carbonate-hosted Pb-Zn deposits in the thrust and fold belt settings of the Central and Eastern Tethys differ from those in the Western Tethys and classic Mississippi Valley Type ore deposits.

The Triassic Pulang porphyry Cu-Au deposit, located in the South Yidun terrane, is the oldest and one of the largest porphyry deposits in the southeastern Tibetan Plateau. Mineralisation occurs mostly in the potassic alteration zone of the Pulang intrusive complex. U-Pb-He triple dating, namely apatite (U-Th)/He, zircon U-Pb, and zircon (U-Th)/He dating, together with inverse thermal modelling, reveals that the Pulang complex was emplaced at a palaeodepth of 5.0-6.5 km at 215 ± 2 Ma. The deep-level emplacement of the complex, coupled with the episodic replenishment of the magma chamber, gave rise to the establishment of a prolonged magmatic-hydrothermal system at Pulang. Although a range of single-grain zircon and apatite (U-Th)/He ages were obtained on each sample, the weighted mean zircon and apatite (U-Th)/He ages vary systematically with elevation, defining a multistage cooling/denudation history at Pulang. Specifically, three phases of cooling were recognised from inverse thermal modelling. Overall, results indicate that the Pulang complex experienced two stages of exhumation at 33 to 45 m/m.y. and 5 to 17 m/m.y. Based on these data, it is estimated that approximately 558-1 099-m thickness of materials have been removed from the Pulang complex during uplift and erosion, including a large volume of ore. The long time span (more than 50 m.y.) of extremely slow cooling and erosion at Pulang could be related to the formation and preservation of a peneplain on the southeastern Tibetan Plateau since the Late Cretaceous. A relict peneplain thus signifies a favourable tectonic environment for the preservation of ancient porphyry systems worldwide., The Triassic Pulang porphyry Cu-Au deposit, located in the South Yidun terrane, is the oldest and one of the largest porphyry deposits in the southeastern Tibetan Plateau. Mineralisation occurs mostly in the potassic alteration zone of the Pulang intrusive complex. U-Pb-He triple dating, namely apatite (U-Th)/He, zircon U-Pb, and zircon (U-Th)/He dating, together with inverse thermal modelling, reveals that the Pulang complex was emplaced at a palaeodepth of 5.0-6.5 km at 215 ± 2 Ma. The deep-level emplacement of the complex, coupled with the episodic replenishment of the magma chamber, gave rise to the establishment of a prolonged magmatic-hydrothermal system at Pulang. Although a range of single-grain zircon and apatite (U-Th)/He ages were obtained on each sample, the weighted mean zircon and apatite (U-Th)/He ages vary systematically with elevation, defining a multistage cooling/denudation history at Pulang. Specifically, three phases of cooling were recognised from inverse thermal modelling. Overall, results indicate that the Pulang complex experienced two stages of exhumation at 33 to 45 m/m.y. and 5 to 17 m/m.y. Based on these data, it is estimated that approximately 558-1 099-m thickness of materials have been removed from the Pulang complex during uplift and erosion, including a large volume of ore. The long time span (more than 50 m.y.) of extremely slow cooling and erosion at Pulang could be related to the formation and preservation of a peneplain on the southeastern Tibetan Plateau since the Late Cretaceous. A relict peneplain thus signifies a favourable tectonic environment for the preservation of ancient porphyry systems worldwide.

Fluid inclusion studies were carried out at Qulong and Chongjiang, which are typical porphyry Cu deposits, and the Bangpu porphyry-related Cu polymetallic deposit. Three types were observed, gas-rich, liquid-rich and daughter mineral-bearing polyphase brine inclusions. The homogenisation temperatures were in the range of 191-550 degrees C, with those of the gas-rich and the daughter mineral-bearing polyphase brine inclusions being similar and in the range 300-550 degrees C. The daughter minerals in the inclusions were mainly halite and chalcopyrite. The coexistence of low-density gas-rich inclusions, high-density liquid-rich inclusions and high-salinity halite-bearing inclusions is attributed to the immiscible separation of fluids, boiling of magma or the mixing of fluids. Ore-forming fluids were derived from the exsolution of magmatic melts that introduced dominant ore metals into the deposits. Cu mineralisation began at high temperature in the post-magmatic phase and mass Cu precipitation in hydrothermal fluids occurred at high to intermediate temperatures., Fluid inclusion studies were carried out at Qulong and Chongjiang, which are typical porphyry Cu deposits, and the Bangpu porphyry-related Cu polymetallic deposit. Three types were observed, gas-rich, liquid-rich and daughter mineral-bearing polyphase brine inclusions. The homogenisation temperatures were in the range of 191-550 degrees C, with those of the gas-rich and the daughter mineral-bearing polyphase brine inclusions being similar and in the range 300-550 degrees C. The daughter minerals in the inclusions were mainly halite and chalcopyrite. The coexistence of low-density gas-rich inclusions, high-density liquid-rich inclusions and high-salinity halite-bearing inclusions is attributed to the immiscible separation of fluids, boiling of magma or the mixing of fluids. Ore-forming fluids were derived from the exsolution of magmatic melts that introduced dominant ore metals into the deposits. Cu mineralisation began at high temperature in the post-magmatic phase and mass Cu precipitation in hydrothermal fluids occurred at high to intermediate temperatures.

Many well-developed stanniferous Pb-Zn-Cu polymetallic ore deposits are found in the Bomi-Tengchong arcuate tectonic belt of the eastern tectonic knot formed by the Indian-Asian continental collision. Isotopic dating of molybdenite from the Honggouyan Cu orebody indicated an ore-forming isochron age of 118.0 +/- 2.4 Ma. The porphyries closely related to the ore-forming process have rock-forming ages of 143-112 Ma, suggesting that the petrogenesis and mineralisation of the porphyries are of the same, Early Yanshanian, epoch. It is suggested that, in the melted granite body within the thickened part of the collisional crust, hydrothermal systems rich in ore-forming fluids were superimposed on the massive sulphide bed, resulting in its enrichment and the formation of the ore deposit., Many well-developed stanniferous Pb-Zn-Cu polymetallic ore deposits are found in the Bomi-Tengchong arcuate tectonic belt of the eastern tectonic knot formed by the Indian-Asian continental collision. Isotopic dating of molybdenite from the Honggouyan Cu orebody indicated an ore-forming isochron age of 118.0 +/- 2.4 Ma. The porphyries closely related to the ore-forming process have rock-forming ages of 143-112 Ma, suggesting that the petrogenesis and mineralisation of the porphyries are of the same, Early Yanshanian, epoch. It is suggested that, in the melted granite body within the thickened part of the collisional crust, hydrothermal systems rich in ore-forming fluids were superimposed on the massive sulphide bed, resulting in its enrichment and the formation of the ore deposit.

The deposit is the third largest LREE deposit in Sichuan and is tectonically located on the northern margin of the Jinpingshan Mountain in the Cenozoic intracontinental orogenic belt of southwestern China. Fluid inclusion studies and stable isotopic data suggest a mantle source for the REE mineralisation and a deep process involving mantle materials and tectonics., The deposit is the third largest LREE deposit in Sichuan and is tectonically located on the northern margin of the Jinpingshan Mountain in the Cenozoic intracontinental orogenic belt of southwestern China. Fluid inclusion studies and stable isotopic data suggest a mantle source for the REE mineralisation and a deep process involving mantle materials and tectonics.

The Gangdese porphyry Cu-Mo system, southern Tibet, (13.6-16.9 Ma) was generated during the postcollision crustal extension. The pre-ore porphyries mainly consist of granodiorite porphyries with ages older than 17 Ma, while the porphyries of the ore-forming stage are mostly composed of monzonitic granite and adamellite porphyries with zircon SHRIMP ages between 14.5 and 17.6 Ma. The post-ore porphyries are comprised of granite porphyries with a young Ar/Ar age of 11.2 Ma. Geochemical studies indicated that these porphyries are of shoshonitic and high-K calc-alkaline series, and show geochemical affinity with adakites derived from partial melting of a thickened basaltic lower crust. The pre-ore porphyries have the lowest contents of sigma-REE and the lowest Sm/Yb ratio (3.0-4.9), coupled with the highest Zr/Sm ratio (50-118). The post-ore porphyries have the highest contents of sigma-REE and intermediate ratios of Sm/Yb (5.9-6.2) and Zr/Sm (34-44). The porphyries of the ore-forming stage are transitional between the pre- and post-ore porphyries in terms of Y content and Sm/Yb and Zr/Sm ratios, but their Sr-Nd isotopic signature is similar to that of the adakitic rocks from Cordillera Blanca. Major, trace-element and Sr-Nd geochemistry of the porphyries indicates that partial melting of a thickened lower crust beneath southern Tibet involved input of materials derived from the depleted mantle., The Gangdese porphyry Cu-Mo system, southern Tibet, (13.6-16.9 Ma) was generated during the postcollision crustal extension. The pre-ore porphyries mainly consist of granodiorite porphyries with ages older than 17 Ma, while the porphyries of the ore-forming stage are mostly composed of monzonitic granite and adamellite porphyries with zircon SHRIMP ages between 14.5 and 17.6 Ma. The post-ore porphyries are comprised of granite porphyries with a young Ar/Ar age of 11.2 Ma. Geochemical studies indicated that these porphyries are of shoshonitic and high-K calc-alkaline series, and show geochemical affinity with adakites derived from partial melting of a thickened basaltic lower crust. The pre-ore porphyries have the lowest contents of sigma-REE and the lowest Sm/Yb ratio (3.0-4.9), coupled with the highest Zr/Sm ratio (50-118). The post-ore porphyries have the highest contents of sigma-REE and intermediate ratios of Sm/Yb (5.9-6.2) and Zr/Sm (34-44). The porphyries of the ore-forming stage are transitional between the pre- and post-ore porphyries in terms of Y content and Sm/Yb and Zr/Sm ratios, but their Sr-Nd isotopic signature is similar to that of the adakitic rocks from Cordillera Blanca. Major, trace-element and Sr-Nd geochemistry of the porphyries indicates that partial melting of a thickened lower crust beneath southern Tibet involved input of materials derived from the depleted mantle.

The Sanjiang metallogenic belt includes a variety of economically important carbonate-hosted Pb-Zn deposits that share some similarities with classic Mississippi Valley-type ore deposits but are hosted within a thrust belt rather than an orogenic foreland. This study aims to clarify the origin of mineralising fluids responsible for this style of mineralisation. The deposits have been subdivided into carbonate-rich and carbonate-fluorite varieties. Combined halogen (Cl, Br and I) and noble gas (He, Ar, Kr, and Xe) analysis of fluid inclusions trapped in ore-stage calcite and fluorite indicate that the ore-forming fluids were dominated by basal brine sedimentary formation waters. Mineralisation occurred as a result of mixing two brines transported through independent aquifers and localised by the intersection of thrust faults and strike-slip faults. The brines acquired their salinity by subaerial evaporation; the shallowest low-temperature brine (50-70 degrees C) was modified by addition of organic gases, H2S and organic Br and I derived from gypsum-bearing, bituminous- and coal-bearing sedimentary units, whereas brines transported more deeply into the Sanjiang belt thrust system and possibly transported along the decollement horizon acquired much higher temperatures and derived metals from regional sediments and 3He and F by mixing with a minor magmato-metamorphic fluid related to emplacement of Cainozoic-age potassic intrusions. Carbonate-fluorite deposits formed in the deepest parts and carbonate-rich deposits formed higher in the thrust system after the deeply sourced fluid had become depleted in fluorine., The Sanjiang metallogenic belt includes a variety of economically important carbonate-hosted Pb-Zn deposits that share some similarities with classic Mississippi Valley-type ore deposits but are hosted within a thrust belt rather than an orogenic foreland. This study aims to clarify the origin of mineralising fluids responsible for this style of mineralisation. The deposits have been subdivided into carbonate-rich and carbonate-fluorite varieties. Combined halogen (Cl, Br and I) and noble gas (He, Ar, Kr, and Xe) analysis of fluid inclusions trapped in ore-stage calcite and fluorite indicate that the ore-forming fluids were dominated by basal brine sedimentary formation waters. Mineralisation occurred as a result of mixing two brines transported through independent aquifers and localised by the intersection of thrust faults and strike-slip faults. The brines acquired their salinity by subaerial evaporation; the shallowest low-temperature brine (50-70 degrees C) was modified by addition of organic gases, H2S and organic Br and I derived from gypsum-bearing, bituminous- and coal-bearing sedimentary units, whereas brines transported more deeply into the Sanjiang belt thrust system and possibly transported along the decollement horizon acquired much higher temperatures and derived metals from regional sediments and 3He and F by mixing with a minor magmato-metamorphic fluid related to emplacement of Cainozoic-age potassic intrusions. Carbonate-fluorite deposits formed in the deepest parts and carbonate-rich deposits formed higher in the thrust system after the deeply sourced fluid had become depleted in fluorine.

Palaeocene-Eocene magmas in the Gangdese belt record the final stage of Neo-Tethyan subduction and are associated with few economic porphyry deposits. In contrast, magmas formed during later stages of the India-Asia collision in the Oligo-Miocene are associated with several large porphyry Cu-Mo+/-Au deposits, especially in the eastern part of the belt. Previously, it was shown that these Oligocene-Miocene magmas were more hydrous than the earlier Palaeocene-Eocene magmas; in this study, it is demonstrated that the later magmas were also more oxidised. It is suggested that these differences reflect the tectonomagmatic evolution of the Cenozoic Gangdese collisional orogen from early collision-related magmatism in the Palaeocene-Eocene to late collisional magmatism in the Miocene. Asthenospheric upwelling following slab breakoff in the Miocene caused interaction between mantle-derived magmas and previously subduction-modified Tibetan lithosphere. The resultant evolved magmas had high oxidation states and water contents, favourable properties for the subsequent formation of magmatic-hydrothermal porphyry Cu-Mo+/-Au deposits., Palaeocene-Eocene magmas in the Gangdese belt record the final stage of Neo-Tethyan subduction and are associated with few economic porphyry deposits. In contrast, magmas formed during later stages of the India-Asia collision in the Oligo-Miocene are associated with several large porphyry Cu-Mo+/-Au deposits, especially in the eastern part of the belt. Previously, it was shown that these Oligocene-Miocene magmas were more hydrous than the earlier Palaeocene-Eocene magmas; in this study, it is demonstrated that the later magmas were also more oxidised. It is suggested that these differences reflect the tectonomagmatic evolution of the Cenozoic Gangdese collisional orogen from early collision-related magmatism in the Palaeocene-Eocene to late collisional magmatism in the Miocene. Asthenospheric upwelling following slab breakoff in the Miocene caused interaction between mantle-derived magmas and previously subduction-modified Tibetan lithosphere. The resultant evolved magmas had high oxidation states and water contents, favourable properties for the subsequent formation of magmatic-hydrothermal porphyry Cu-Mo+/-Au deposits.

The Yao'an porphyry Au system, Machangqing porphyry Cu-Mo system and Beiya porphyry-skarn Au system, are spatially and temporally associated with potassic felsic intrusions emplaced during the Eocene to Oligocene (37-33 Ma) in a postcollisional intracontinental setting in western Yunnan. It is postulated that continental collision may have preferentially thickened the continental lithospheric mantle adjacent to the Jinsha suture, in which overthickened lower continental lithospheric mantle was subsequently removed, inducing melting of residual metasomatised lithospheric mantle as well as lower crust. The gold-rich Yao'an and Beiya intrusions are alkaline and potassic, characterised by high zircon 18-O values (higher than 6.5 per mille), consistent with supracrustal contributions. In contrast, the Cu-Mo-rich Machangqing intrusions are high-K calc-alkaline with mantle-like zircon 18-O values (lower than 6.5 per mille) and juvenile Hf isotope signatures, indicating negligible supracrustal recycling. Empirically, source compositions played an important role in determing the metal endowment among intrusions formed under the same tectonic setting with similar ages in western Yunnan, where Au tends to have been associated with alkaline and potassic melts with a supracrustal contribution, whereas Cu-Mo mineralisation seems to have been more related to juvenile crustal sources with little supracrustal influence., The Yao'an porphyry Au system, Machangqing porphyry Cu-Mo system and Beiya porphyry-skarn Au system, are spatially and temporally associated with potassic felsic intrusions emplaced during the Eocene to Oligocene (37-33 Ma) in a postcollisional intracontinental setting in western Yunnan. It is postulated that continental collision may have preferentially thickened the continental lithospheric mantle adjacent to the Jinsha suture, in which overthickened lower continental lithospheric mantle was subsequently removed, inducing melting of residual metasomatised lithospheric mantle as well as lower crust. The gold-rich Yao'an and Beiya intrusions are alkaline and potassic, characterised by high zircon 18-O values (higher than 6.5 per mille), consistent with supracrustal contributions. In contrast, the Cu-Mo-rich Machangqing intrusions are high-K calc-alkaline with mantle-like zircon 18-O values (lower than 6.5 per mille) and juvenile Hf isotope signatures, indicating negligible supracrustal recycling. Empirically, source compositions played an important role in determing the metal endowment among intrusions formed under the same tectonic setting with similar ages in western Yunnan, where Au tends to have been associated with alkaline and potassic melts with a supracrustal contribution, whereas Cu-Mo mineralisation seems to have been more related to juvenile crustal sources with little supracrustal influence.