Magmatic-hydrothermal System Research Articles

Magmatic-hydrothermal evolution of rare metal pegmatites from the Mesoproterozoic Orange River pegmatite belt (Namaqualand, South Africa)

The 450 km long Orange River pegmatite belt intruded the Namaqua Sector of the Mesoproterozoic Namaqua-Natal Province, Southern Africa, at ca. 1 Ga. The western part of the belt is characterized by the occurrence of LCT pegmatites locally mineralized in Li, Ta, Nb, Be and Bi. Most of these mineralized pegmatites display zonation with a quartz-feldspar-muscovite-garnet-beryl-bearing aplite border and wall zone, a quartz-feldspar-spodumene-lepidolite-bearing intermediate zone, and a quartz-K-feldspar core. The pegmatites and their granodioritic country rocks commonly show evidence of albitization and greisenization (i.e. secondary muscovitization). In this study, detailed petrographic observations and the compositions of mica, feldspar, spodumene and Nb-Ta oxide minerals are reported. This information is combined with bulk country rock compositions and new U-Pb zircon and monazite ages plus Sm-Nd isotope compositions of monazite to constrain the origin and magmatic-hydrothermal evolution of weakly and strongly mineralized LCT pegmatites.The Li-Ta-Be Kokerboomrand I pegmatite emplaced at ca. 985 Ma during the main stage of pegmatite emplacement in the Orange River belt and regional strike-slip deformation. It has εNd(t)monazite = −14 ± 3 and potentially formed by partial melting of Paleoproterozoic rocks from the Richtersveld magmatic arc. Alternatively, Mesoproterozoic sediments of the Bushmanland Subprovince may also provide a suitable magma source for the Kokerboomrand I pegmatite.The rare metal contents of muscovite and columbite group minerals (CGM) increase from the weakly mineralized to strongly mineralized pegmatites, suggesting early-stage fractional crystallization or variable partial melting conditions. Mica Nb/Ta values of <14 and K/Rb ratios of <40 can be used as geochemical tools for Li-Ta-(Nb)-Be exploration in the region, and possibly in other pegmatite belts worldwide.Rare metal-bearing minerals crystallized throughout the magmatic-hydrothermal evolution of mineralized pegmatites. During the magmatic-dominated stage I, constitutional zone refining likely induced a decrease of spodumene Fe contents and increase of CGM Ta contents toward the pegmatite core. Stage II marks the pervasive circulation of an immiscible hydrosaline melt. This stage is characterized by the replacement of the primary mineral assemblage by lamellar albite (cleavelandite), (fluor)calciomicrolite and Cs-Ta-rich Li-muscovite and zinnwaldite. Stage III represents the progressive transition from a magmatic-hydrothermal system dominated by a Li-Cs-Ta-rich hydrosaline melt toward a system mainly involving (Li)-Cs-(Ta)-Bi-rich aqueous fluids. This stage is characterized by the crystallization of lepidolite and zero-valence-dominant pyrochlore as well as strong localized greisenization and Bi mineralization.Magmatic-hydrothermal alteration of the immediate country rock of the mineralized pegmatites is marked by the crystallization of albite, Li-Ta-Cs-rich mica, various Nb-Ta oxide minerals, and led to a strong decrease of the whole-rock Nb/Ta ratio plus significant rare metal enrichment.Our findings from the Orange River belt demonstrate that an important role can be ascribed to melt-melt and melt-fluid immiscibility and metasomatism in the formation of pegmatite-related rare metal deposits. Greisens and albitites associated with pegmatites and their immediate country rocks can be considered as favorable targets for Li-Ta mineral exploration. Strong and pervasive metasomatism across the mineralized pegmatites and their country rocks suggests involvement of a parental medium that was highly enriched in water.

Lithium isotope fractionation during fluid exsolution: Implications for Li mineralization of the Bailongshan pegmatites in the West Kunlun, NW Tibet

Granitic pegmatites are considered significant host rocks for the rare metal deposits. However, the enrichment mechanisms for the rare metal elements (e.g., Li, Be, Nb and Ta) remain debated. Here we report the whole-rock and mineral (e.g., muscovite and spodumene) major, trace elements and Li isotopic compositions of the Bailongshan granitic pegmatites in the West Kunlun, NW Tibet, to address this issue. The Bailongshan pegmatites (hosting a super-large Li–Rb polymetallic deposit) are composed of Li-poor and Li-rich pegmatites. The Li-poor pegmatites display high δ7Li values in the whole rock (2.30–4.94‰) and muscovite (2.22–7.55‰). In contrast, the Li-rich pegmatites show low δ7Li values in the whole rock (−1.89 to 0.35‰), muscovite (−3.39 to 4.49‰) and spodumene (−2.83 to 1.87‰). These results, together with the variations of the elements, suggest that the Li-poor and Li-rich pegmatites were produced by the melt-fluid separation during the late stage of granitic magma evolution. This means that the Li-poor pegmatites were formed in a H2O-poor silicate-rich melt system, while the Li-rich pegmatites were generated in a H2O-rich silicate-poor melt (supercritical fluid) system. The melt-fluid separation can lead to significant Li isotope fractionation, with 7Li enriched in the strongly-bonded residual silicate melt, and 6Li preferring to weaker hydrated bonds in the fluid. Alternatively, the Li-rich pegmatites enriched in 6Li could have been induced by preferential accumulation of the faster-diffusing 6Li in the supercritical or near critical fluid. The Li-rich pegmatites experienced extensive crystal-fluid interaction in a relatively closed magmatic-hydrothermal system, which resulted in the leaching and reprecipitation of ore-forming elements, but produced restricted Li isotope fractionation. The exsolved supercritical fluid is more enriched in alkali-, fluxing components (Li, Rb, Cs, P and F) by the continuous interaction with the residual silicate melt. Therefore, the supercritical fluid exsolution plays an important role in the Li isotope fractionation and rare metal mineralization.

Fault-controlled fluid evolution in the Xitian W–Sn–Pb–Zn–fluorite mineralization system (South China): Insights from fluorite texture, geochemistry and geochronology

Fluorite is one of the most common minerals in the granite-related hydrothermal systems, and widely distributed in the Xitan W–Sn polymetallic ore field (South China). It existed from the early W–Sn stage to the middle Pb–Zn stage and then to the late fluorite stage, thus responsible for the Xinggao and Guangming fluorite deposits in the region. In this research, textural, geochemical and geochronological analyses of fluorites were used to reconstruct the fluid evolutionary history and its bearings on fault activities in the ore field. The fluorites from the ore field yielded a Sm–Nd isochron age of 153.3 ± 8.0 Ma (initial 143Nd/144Nd = 0.511871 ± 0.000013, MSWD = 1.5) which is consistent to the timing of the W–Sn ore-forming stage within the error. This suggests that the fluorites were formed in the same time with the W–Sn ores. And the average value of εNd(t) is similar to those of the Jurassic granites (εNd(t) = −9.2 to −7.3) in the ore field. This indicates that fluorite mineralization is mainly related to the Jurassic granites, and the basement rocks could be the source for the ore-forming materials. From the early stage fluorites (coexisting with wolframite) to the late fluorite-only veins, the total amount of rare earth elements (∑REE) in the fluorites substantially decreases (average values vary from 174 to 37.2 ppm), especially the LREE (La/Lu values decrease from 80.0 to 16.6). In addition, the ore-forming elements (e.g., W, Sn, Mo) in the fluorites also decrease significantly with time. And the low δ18OH2O values (−4.30‰ to −3.90‰) and moderate δD values (−63.8‰ to −59.6‰) in the fluorites suggest that the late fluorite stage was contributed largely from meteoric water. Combined with previously reported fluid inclusion data in the ore field, we propose that the W–Sn mineralization was related to fluid boiling and mixing, the Pb–Zn ore was formed from the changing of the redox environment from oxidizing to reducing, and the fluorites were formed due to rapid cooling. The formation of the W–Sn, Pb–Zn, and fluorite ore-forming zones belong to a single magmatic-hydrothermal system but was controlled by the fault evolutionary processes from the early granite plutons intrusion to the large-scale crustal extension in the Xitian ore field.

HFSE-REE Transfer Mechanisms During Metasomatism of a Late Miocene Peraluminous Granite Intruding a Carbonate Host (Campiglia Marittima, Tuscany)

The different generations of calc-silicate assemblages formed during sequential metasomatic events make the Campiglia Marittima magmatic–hydrothermal system a prominent case study to investigate the mobility of rare earth element (REE) and other trace elements. These mineralogical assemblages also provide information about the nature and source of metasomatizing fluids. Petrographic and geochemical investigations of granite, endoskarn, and exoskarn bodies provide evidence for the contribution of metasomatizing fluids from an external source. The granitic pluton underwent intense metasomatism during post-magmatic fluid–rock interaction processes. The system was initially affected by a metasomatic event characterized by circulation of K-rich and Ca(-Mg)-rich fluids. A potassic metasomatic event led to the complete replacement of magmatic biotite, plagioclase, and ilmenite, promoting major element mobilization and crystallization of K-feldspar, phlogopite, chlorite, titanite, and rutile. The process resulted in significant gain of K, Rb, Ba, and Sr, accompanied by loss of Fe and Na, with metals such as Cu, Zn, Sn, W, and Tl showing significant mobility. Concurrently, the increasing fluid acidity, due to interaction with Ca-rich fluids, resulted in a diffuse Ca-metasomatism. During this stage, a wide variety of calc-silicates formed (diopside, titanite, vesuvianite, garnet, and allanite), throughout the granite body, along granite joints, and at the carbonate–granite contact. In the following stage, Ca-F-rich fluids triggered the acidic metasomatism of accessory minerals and the mobilization of high-field-strength elements (HFSE) and REE. This stage is characterized by the exchange of major elements (Ti, Ca, Fe, Al) with HFSE and REE in the forming metasomatic minerals (i.e., titanite, vesuvianite) and the crystallization of HFSE-REE minerals. Moreover, the observed textural disequilibrium of newly formed minerals (pseudomorphs, patchy zoning, dissolution/reprecipitation textures) suggests the evolution of metasomatizing fluids towards more acidic conditions at lower temperatures. In summary, the selective mobilization of chemical components was related to a shift in fluid composition, pH, and temperature. This study emphasizes the importance of relating field studies and petrographic observations to detailed mineral compositions, leading to the construction of litho-geochemical models for element mobilization in crustal magmatic-hydrothermal settings.

Origin of the Xiaohekou skarn copper deposit and related granitoids in the Zha-Shan ore cluster area, South Qinling, China

The Xiaohekou copper deposit is one of the few typical skarn-type, commercial deposits in the Zha-Shan ore cluster area in the eastern part of South Qinling. The ore-related granitoids in the Xiaohekou mining district include a number of small plutons of granodiorite porphyry and granite porphyry, as well as numerous dykes. They are characterized by relatively low SiO2 (65.9–73.3 wt%) and MgO (0.26–1.72 wt%) contents, variable Mg# (29.4–64.0) values, high K2O (3.11–5.75 wt%) content and negligible δEu (1.00–1.15) values. The samples also exhibit depletion in Cr, Ni, Nb, Ta, and Ti content, and high Sr/Y (46.6–64.7) and La/Yb (17.0–25.0) ratios. These features are similar to those of high-K calc-alkaline adakite-like magma formed by partial melting of thickened lower crust in continental collision zones or intracontinental settings. The majority of the samples have TDM2(Hf) of 1.5–1.2 Ga, corresponding to weakly negative εHf(t) values (−4.75 to −0.13) typical of crustal material, but more than one quarter have TDM1(Hf) of 0.80–0.71 Ga, corresponding to positive εHf(t) values of +0.07 to +2.45, indicating that the granitoids resulted from partial melting of Mesoproterozoic lower crustal rocks with significant input from enriched lithospheric mantle-derived magmas. Zircons from the Xiaohekou granitoids have ΔFMQ values concentrated around −0.62 to +5.54, most of which show the magma fO2 of FMQ to HM, in accordance with the widespread occurrence of magnetite, hematite and specularite in the Xiaohekou skarn system, which is an indicator of relatively high fO2 for a magmatic–hydrothermal system. The granitoids exhibit similar or even higher Ce4+/Ce3+ (average of 452) and Eu/Eu* (average of 0.72) values in comparison with those of fertile Cu deposits worldwide, indicating that the Xiaohekou granitoids may possess the potential to form a large magmatic–hydrothermal Cu deposit. Zircons of the granitoids show obvious positive correlations between oxidation indices (Ce and Eu anomalies, Ce4+/Ce3+ ratios, and ΔFMQ values) and εHf(t) values, implying the involvement of an oxidized mantle component which might have caused the fO2 elevation and played an important role in the formation of Cu deposits. The zircon U–Pb ages (141.3 ± 1.3 and 138.1 ± 2.0 Ma) of the Xiaohekou ore-related granitoids obtained in this study are similar to the zircon U–Pb and molybdenite Re–Os ages yielded from porphyry Mo mineralization at the Chigou and Lengshuigou deposits in the Zha-Shan ore district, indicating that they are possibly part of a single tectonic, magmatic, and metallogenic event in the Yanshan orogeny. The ore-related granitoids in the Xiaohekou area were formed in a post-collisional compression–extension transition regime during the Early Cretaceous Qinling intracontinental orogeny. The orogeny can be attributed to the far-field effect of a switch from pre-Mesozoic Tethyan tectonics to Late Mesozoic Pacific tectonics. This triggered a stress field transition from N–S to E–W trending and from intracontinental subduction thickening to large-scale lithospheric delamination and thinning.

Hydrothermal evolution and ore precipitation of the No. 2 porphyry Cu–Au deposit in the Xiongcun district, Tibet: Evidence from cathodoluminescence, fluid inclusions, and isotopes

The No. 2 porphyry Cu–Au deposit in the Xiongcun district forms part of the Gangdese porphyry copper belt of Tibet. This study clarifies the fluid evolution and ore precipitation mechanisms of the magmatic-hydrothermal system that formed the deposit by combining the results of fluid inclusion petrography, microthermometry, scanning electron microscope-cathodoluminescence imaging, and stable isotope analyses of multiple quartz-dominated veins. Four distinct sets of quartz-dominated veins and eight generations of quartz (Q1–Q8) within the veins were identified, namely from early to late, early barren quartz veins (V1) comprised of equigranular CL-bright Q1 quartz, quartz–pyrite–chalcopyrite ± magnetite veins (V2) containing early equigranular CL-bright Q1 quartz and later CL-gray or CL-dark Q2–3 (Q2 + Q3) quartz grains intergrown with Cu–Fe sulfides, quartz–molybdenite ± pyrite ± chalcopyrite veins (V3) comprised of quartz grains (Q4–Q6) characterized by subhedral comb-like textures with well-developed oscillatory growth zoning, and late quartz veins (V4) containing CL-gray Q7 quartz with euhedral growth zones and later CL-dark Q8 quartz. Fluid inclusions in these veins can be classified into six types: B40, B40H, B80, B15H, B15H+, and B15. The B40 and B40H inclusions; B80 inclusions; and B15, B15H, and B15H+ inclusions contain vapor bubbles occupying 30–60 vol%, >70 vol%, and 5–25 vol%, respectively; in addition, B15H, B15H+, and B40H inclusions contain transparent daughter minerals (halite, and in some cases, sylvite). Raman spectra showed that CO2 is only present in B40 and B80 inclusions. In the Q1 quartz in V1 and V2 veins, the dominant type of inclusions is B40, which have homogenization temperatures (Th) of 278 °C–389 °C (peaking at 310 °C–330 °C) and salinities of 2.0–12.8 wt% NaCl equiv. In Q2–3 quartz in V2 veins, all inclusion types were observed. These were trapped at temperatures of approximately 325 °C–340 °C and had salinities of 1.8–69.7 wt% NaCl equiv. In V3 veins, only B15H and B15 inclusions were observed, which had Th values of 171 °C–320 °C (peaking at 240 °C–260 °C) and 173 °C–317 °C (peaking at 210 °C–230 °C) and salinities of 28.7–33.9 wt% NaCl equiv and 5.6–23.1 wt% NaCl equiv, respectively. In V4 veins, only B15 inclusions were observed. Primary B15 inclusions in V4 veins yielded Th values of 166 °C–229 °C (peaking at 170 °C–200 °C) and salinities of 5.1–17.1 wt% NaCl equiv. The 3He/4He and 40Ar/36Ar ratios of the fluid inclusions exhibited the ranges of 0.08–0.84 Ra and 451.3–1567.8, respectively, and the δ18Ofluid and δDfluid values varied from −3.2‰ to 5.8‰ and −92.8‰ to −80.3‰, respectively. By integrating all results from the fluid inclusion, cathodoluminescence, and isotopic analyses, we conclude that the initial ore-forming fluids of the No. 2 deposit were low-salinity, CO2-rich single-phase fluids of magmatic origin. Subsequently, fluid immiscibility developed in the initial ore-forming fluids, generating hypersaline liquid and low-salinity vapor phases and leading to the separation of a CO2 phase plus chalcopyrite precipitation from the fluids. As meteoric water was injected into the hydrothermal system, the ore-forming fluids gradually evolved to become meteoric water-dominated, low temperature, low-salinity, and CO2-poor; in addition, fluid-cooling due to the meteoric water input resulted in molybdenite precipitation.

Geochronology and Geochemistry of Uraninite and Coffinite: Insights into Ore-Forming Process in the Pegmatite-Hosted Uraniferous Province, North Qinling, Central China

The biotite pegmatites in the Shangdan domain of the North Qinling orogenic belt contain economic concentrations of U, constituting a low-grade, large-tonnage pegmatite-hosted uraniferous province. Uraninite is predominant and ubiquitous ore mineral and coffinite is common alteration mineral after initial deposit formation. A comprehensive survey of the uraninite and coffinite assemblage of the Chenjiazhuang, Xiaohuacha, and Guangshigou biotite pegmatites in this uraniferous province reveal the primary magmatic U mineralization and its response during subsequent hydrothermal events. Integrating the ID-TIMS (Isotope Dilution Thermal Ionization Mass Spectrometry) 206Pb/238U ages and U-Th-Pb chemical ages for the uraninites with those reported from previous studies suggests that the timing of U mineralization in the uraniferous province was constrained at 407–415 Ma, confirming an Early Devonian magmatic ore-forming event. Based on microtextural relationships and compositional variation, three generations of uranium minerals can be identified: uaninite-A (high Th-low U-variable Y group), uranite-B (low Th-high U, Y group), and coffinite (high Si, Ca-low U, Pb group). Petrographic and microanalytical observations support a three-stage evolution model of uranium minerals from primary to subsequent generations as follows: (1) during the Early Devonian (stage 1), U derived from the hydrous silicate melt was mainly concentrated in primary magmatic uaninite-A by high-T (450–607 °C) precipitation; (2) during the Late Devonian (stage 2), U was mobilized and dissolved from pre-existing uraninite-A by U-bearing fluids and in situ reprecipitated as uraninite-B under reduced conditions. The in situ transformation of primary uraninite-A to second uraninite-B represent a local medium-T (250–450 °C) hydrothermal U-event; and (3) during the later low-T (100–140 °C) hydrothermal alteration (stage 3), U was remobilized and derived from the dissolution of pre-existing uraninite by CO2- and SiO2-rich fluids and interacted with reducing agent (e.g., pyrite) leading to reprecipitation of coffinite. This process represents a regional and extensive low-T hydrothermal U-event. In view of this, U minerals evolved from magmatic uraninite-A though fluid-induced recrystallized uraninite-B to coffinite, revealing three episodes of U circulation in the magmatic-hydrothermal system.

Mineralogical constraints on the genesis of the Dahu quartz vein-style Au-Mo deposit, Xiaoqinling gold district, China: Implications for phase relationships and physicochemical conditions

The quartz vein-style Dahu Au-Mo deposit, with an average grade of 6.8 g/t for 38 tons Au, and an average grade of 0.24% for 100,000 tons Mo, is situated in the Xiaoqinling region in the northernmost part of Qinling orogen in China. It is characterized by enrichment of native gold, molybdenite, telluride and Bi-sulfosalt. The current understanding of telluride and Bi-sulfosalt mineralization in the Dahu Au-Mo deposit is very poor, and this paper is the first systematic study of these minerals in this deposit. The Au-Mo ores occur mainly as veins and stockworks as well as disseminated in quartz veins, and they are hosted by biotite-plagioclase gneiss, amphibole-plagioclase gneiss, and amphibolite of the Archaeozoic Taihua Group. Four paragenetic stages of mineralization are recognized that reflect early formation of sulfide minerals and subsequent precipitation of telluride minerals: (I) quartz-K-feldspar-pyrite-molybdenite, (II) quartz-pyrite-molybdenite, (III) sulfide-telluride-sulfosalt-gold, and (IV) carbonate-barite. The telluride minerals are mainly altaite, tellurobismuthite, and tetradymite, and to a minor extent calaverite, petzite, hessite, and stützite. Some Bi-sulfosalt minerals also exist in the deposit, including aikinite, lindströmite, saddlebackite, krupkaite, and hammarite. Of these minerals, saddlebackite, krupkaite and hammarite are reported in this deposit for the first time herein. The Au-Ag-Te-Bi-S minerals substantially formed in the Dahu Au-Mo deposit under conditions of T = 260 °C, P ≈ 100 MPa, pH = 3.9 to 7.9, logƒO2 = −40.9 to −33.8, logƒTe2 = −12.5 to −7.5, logƒS2 = −13.5 to −8.2, logƒH2S = −2.4 to −0.3 and logαAu+(aq)/αAg+(aq) = −6.7 to −6.2. The deposit formed from an ore-forming fluid dominated by HTe- or/and Te22−, in which Au was transported in the forms of Au(HS)2− and/or an unknown aqueous Te species (e.g., AuTe2−). Furthermore, during the mineralization stages of the Dahu deposit, the ore-forming fluid evolved from an initial oxidation type to a later relative reduction type, and the telluride minerals, Bi-sulfosalt minerals and native gold were formed in a relatively reduced condition. The Au-Ag-Te-Mo-Bi metal associations in the Dahu Au-Mo deposit were derived from a magmatic-hydrothermal system during the Late Triassic.

A genetic link between iron oxide-apatite and iron skarn mineralization in the Jinniu volcanic basin, Daye district, eastern China: Evidence from magnetite geochemistry and multi-mineral U-Pb geochronology

Abstract Various styles of ore deposits may form from a single magmatic-hydrothermal system. Identification of a possible genetic link between different ore types in a region is not only of critical importance for a better understanding of the magmatic-hydrothermal processes, but can also help in successful mineral exploration. Both iron oxide-apatite (IOA) and iron skarn deposits are closely associated with intrusive rocks of intermediate to felsic in composition, but whether these two ore types can form from the same magmatic intrusion remains poorly understood. In this study, we present a comparative study between a newly identified subsurface IOA ore body located at the apex of a diorite porphyry and the iron skarn ore bodies located immediately above it in the Jinniu volcanic basin of the Daye district, Middle-Lower Yangtze River metallogenetic belt (MLYRMB), eastern China in order to highlight a genetic link between these two styles of mineralization. The IOA ores are dominated by Ti-rich magnetite with variable amounts of fluorapatite, diopside, and actinolite. This mineralogical assemblage is distinctly different from the iron skarn ores, which consist mainly of Ti-depleted magnetite and subordinate pre-ore garnet and diopside, and post-ore quartz, chlorite, calcite, and pyrite. In addition, magnetite from the IOA ores is characterized by well-developed ilmenite lamellae and has high concentrations of Ni, V, Co, and Ga, consistent with high temperature crystallization, whereas magnetite grains from the iron skarn ores usually exhibit oscillatory growth zones and contain much lower Ni, V, Co, and Ga, indicating their formation under relatively low temperatures. Titanite and fluorapatite from the IOA ores have U-Pb ages of 132.5 ± 2.4 Ma to 128.4 ± 3.0 Ma, which match a titanite U-Pb age for the associated iron skarn ores (132.3 ± 2.0 Ma), and are consistent with zircon U-Pb ages for the ore-hosting diorite porphyry (130.4 ± 0.7 Ma to 130.3 ± 0.5 Ma). This age consistency supports a possible genetic link among the diorite porphyry, IOA ores, and iron skarn ores. We propose that the IOA and skarn ores are the products of two consecutive mineralization stages of the same magmatic-hydrothermal system, involving a high-temperature, hypersaline fluid coexisting with the diorite porphyry magma during emplacement and a subsequent low temperature, diluted hydrothermal fluid. Other IOA and iron skarn deposits of similar ages (130 Ma) are found in a series of volcanic basins in the MLYRMB, which forms one of the world’s largest IOA metallogenic belts. The close association of the two ore styles identified at Daye provides a useful exploration guide for IOA and iron skarn deposits both on a local and regional scale.

Ore formation at the Washan iron oxide–apatite deposit in the Ningwu Ore District, eastern China: Insights from in situ LA-ICP-MS magnetite trace element geochemistry

Iron oxide–apatite (IOA) deposits are an important type of iron deposit that may host large reserves of iron and other elements. The Washan deposit in the Ningwu Ore District is a classic giant IOA deposit hosted by porphyritic diorite. At Washan, four Fe mineralization stages have been identified with clear crosscutting relationships, forming four types of ores: disseminated ores, breccia ores, and magnetite–actinolite and magnetite–apatite–actinolite veins. Trace element concentrations and single-grain geochemical profiles of magnetite from the four Fe mineralization stages were obtained via laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The geochemical profiles show consistent Ti, V, Mg and Al contents from cores to rims, indicating that magnetite might have crystallized quickly under relatively stable conditions in each stage. Compatible element (e.g., Co, V, Ni, and Cr) contents of the Washan magnetite are similar to those of magmatic Fe–Ti–V deposits, with high V and Ti contents, indicating a close magmatic link. Increasing Mg, Al, Mn, Ni and Ga contents and decreasing Cr content from early to late stages imply increasingly intense reactions between Fe-bearing fluids and country rocks (e.g., diorite and evaporites), which also suggests a magmatic-hydrothermal origin. We propose a new genetic model for ore formation at the Washan IOA deposit. First, an Fe-rich liquid, which may have formed via liquid immiscibility, ascended through the magma system, resulting in the disseminated ores and albite alteration in the porphyritic diorite. With cooling and crystallization of the magma, the intrusive rocks developed fractures and brecciation, which may have provided pathways for Fe-bearing fluids. After the breccia (or massive) ores formed, the pathways would have been quickly sealed by mineral precipitation. Continuous liquid immiscibility and magma crystallization may have produced similar fluids with more sedimentary material involved and its markers displayed. When the fluid pressure overcame the lithostatic pressure, the fractures that developed may have provided the necessary conduits for emplacement of the magnetite–actinolite and magnetite–actinolite–apatite veins. Subsequently, the magmatic-hydrothermal system might have remained active during cooling and differentiation, while pyrite–quartz and calcite veins formed.

Constraints on the Formation of Granite-Related Indium Deposits

Abstract The use of indium in modern technologies has grown in recent decades, creating a growth in indium demand; thus, there is a need to constrain the spatial and temporal distribution of indium-bearing, granite-related deposits. Toward this end, a conceptual model and exploration vectors for the formation of granite-related indium deposits have been developed. The magmatic-hydrothermal system is modeled by consideration of crystal-melt and vapor-melt equilibria. The model calculates the efficiency of removal of indium from a melt into a volatile phase, which may serve as a component of an ore-forming fluid. The results of the model suggest that as the proportion of ferromagnesian minerals increases in the associated granites, the probability of indium ore formation decreases. Further, for a given modal proportion of ferromagnesian minerals, as the modal proportion of amphibole increases, the probability of indium ore formation decreases. Lastly, for a given modal proportion of biotite, as the magnesium content of the biotite increases (as would result from increasing oxidation of the magmatic system), the probability of indium ore formation decreases. Granites with the highest probability of being associated with indium ore formation will typically be part of A- or S-type igneous systems and will likely be highly fractionated (e.g., A-type topaz granites). I-type granites will generally have a lower potential of being associated with indium-bearing deposits. However, some I-type granites may be associated with indium-bearing deposits if the deposits contain granites (sensu stricto) or other related rocks (e.g., alaskites) that lack amphibole or other ferromagnesian phases.

Stable isotope geochemistry of Chargar epithermal deposit: Constraints on epithermal systems in the Tarom metallogenic belt, NW Iran

The Chargar deposit in the southern part of Tarom metallogenic belt of the Alborz structural zone, NW Iran, shows a volcaniclastic-hosted, low-sulfidation epithermal gold mineralization. The host rocks are part of the Eocene volcanic and volcaniclastic sequence of the Karaj Formation. The main host rock is an andesitic lapilli-lithic tuff. The main ore minerals include chalcopyrite and gold and the gangue minerals are quartz, barite, and calcite. The calculated δ34SH2S values based on sulfide minerals for the Chargar shows a homogeneous signature ranging from −7.6 to −5.6‰, in the Khalifelou deposit range between −5.2 and −1.9‰ and in the Aliabad-Khanchay deposit from −8.1 to −5.5‰. Negative sulfur isotope values and the occurrence of framboidal pyrite in the volcaniclastic host rocks suggest a volcano-sedimentary origin for the sulfur. The Chargar calculated δ34SH2S values based on barite supplied δ34S values between +16.5 and +22.5‰. These are heavier than possible magmatic distribution and require heavier non-magmatic reduced sulfur sources. The sulfur isotope data imply essentially a volcano-sedimentary and sulfate origin for sulfur. The calculated δ34SH2S values from the Chodarchay deposit ranging from −1.6 to +5‰ and in the Goloujeh between −9.6 to +7.2 compatible with a magmatic sulfur source. The Calculated δ18O values for Chargar hydrothermal ore-forming fluids range from +1 to +1.3‰. The δ18O values for Khalifelou and Aliabad-Khanchay hydrothermal ore-forming fluids vary from +0.6 to +3.6‰ and from +0.8 to +3.6‰, respectively. The oxygen data suggest that hydrothermal fluids resulted from meteoric fluids. The δ18O values of Goloujeh hydrothermal ore-forming fluids are between 0.7 and 7.7‰ and emphasize on magmatic fluid - meteoric water. Oxygen and S isotopic signatures of barite combined with mineralogical features show characteristics of a magmatic-hydrothermal system. Chargar demonstrates similarity with Khalifelou and Aliabad-Khanchay epithermal deposits in the southern part of Tarom belt. These deposits are different from Chodarchay porphyry-epithermal and Goloujeh epithermal deposit in the northern part of the belt in terms of isotopic data, sulfur and fluid sources.

The 109 porphyry Cu deposit in the western Tianshan orogenic belt, NW China: An example of Cu mineralization in a reduced magmatic-hydrothermal system in an extensional setting

The 109 porphyry Cu deposit in the western Tianshan orogenic belt, NW China, is hosted in albite porphyry. The albite porphyry is metaluminous to peraluminous and alkaline in terms of composition, and has an affinity of A-type granite, and is considered to have formed in an extensional tectonic setting. Zircon grains from the albite porphyry yielded a weighted mean 238U/206Pb age of 300 ± 4 Ma (95% confidence) by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). The age can be considered to be the crystallization age of the 109 albite porphyry. The zircon grains have Ce4+/Ce3+ ranging from 10.8 to 50.5. The ore minerals mainly include chalcopyrite, bornite and chalcocite, and the absence of magnetite, hematite and sulfates. The oxygen fugacity (fO2) was estimated to be below the quartz-fayalite-magnetite (QFM) + 2 buffer using the Ti-in-zircon thermometer. We therefore assumed that the 109 Cu deposit formed in a reduced magmatic-hydrothermal system, which is similar to the coeval Cu deposits elsewhere in the western Tianshan orogenic belt, indicating that they may have the same the reduced ore system is likely attribute to an extensional tectonic setting during the late Carboniferous in the western Tianshan orogenic belt. Sulfides in the ores display quench texture or exsolution texture. The rim of each sulfide grains always have δ34S higher than the cores, which is attributed to a fast decrease of temperature and degassing of sulfur from ore-forming fluid. The sulfur degassing may lead to the progressive increase of the fO2 of the ore-forming fluids. The ore-forming fluids with high fO2 can contain more sulfur leading to the formation of the 109 Cu deposits

Temporal and spatial variations in characteristics of fluid inclusions in epizonal magmatic-hydrothermal systems: Applications in exploration for porphyry copper deposits

Temporal and spatial variations in the room temperature phase relations of fluid inclusions serve as a proxy for the PTX properties of fluids associated with emplacement and crystallization of a shallow epizonal intrusion following the “Burnham Model”. Accordingly, during magma ascent, hydrous magmas approach and achieve volatile saturation in response to decreasing pressure (“first boiling”) and/or as a result of cooling and crystallization of anhydrous mineral phases (“second boiling”). In both cases, a magmatic aqueous fluid phase will exsolve from the volatile-saturated silicate melt. Fluid inclusions that trap the exsolved magmatic fluid show predictable room temperature phase relations, compositions, and microthermometric characteristics indicative of the pressure and temperature conditions of the trapping environment.We model aqueous phase equilibria as a function of temperature, pressure, and fluid composition. The composition and phase behavior of the magmatic aqueous fluid phase is adequately approximated by the system H2O-NaCl, and the PVTX characteristics of the magmatic fluids may be determined at any temperature and pressure using phase equilibrium data for this binary system. Then, PVTX data for the system H2O-NaCl are used to predict the room temperature phase relations and homogenization temperatures of fluid inclusions that trap the magmatic fluid at various times and locations in the magmatic-hydrothermal system. The temperature at any position in the system is based on established numerical models of conductive and convective cooling of shallow plutons, and the pressure at any depth is calculated assuming that hydrostatic conditions apply at temperatures <400 °C, and that lithostatic conditions are applicable at higher temperatures.We apply the model to four different stages during the crystallization of a shallow, intermediate composition magma, beginning in the early stages of crystallization and immediately following initial volatile saturation, and ending with complete crystallization of the melt. Mapping the stable fluid phase fields onto a cross-section of the pluton allows us to predict the characteristics of fluid inclusions trapped at various times and locations in the overall system. The fluid inclusion characteristics are predicted along five depth profiles that extend from the center of the pluton to the periphery. The results show good agreement with numerous studies that describe the distribution of halite-bearing, vapor-rich, and two-phase, liquid-rich inclusions in porphyry copper deposits.The results of this study may be applied in exploration for porphyry copper mineralization, as well as other magmatic-hydrothermal porphyry deposits in which the magmatic fluids can be approximated by the system H2O-NaCl. Importantly, halite-bearing fluid inclusions occur only within the pluton and in the immediately surrounding wallrocks, which represents the part of the system that often hosts mineralization. Similarly, fluid inclusion assemblages comprised of only vapor-rich inclusions occur in the near-surface, sub-volcanic part of the system, whereas coexisting halite-bearing and vapor-rich inclusions characterize the deeper parts of the system. The distribution of fluid inclusion types constrains the vertical and lateral position within the overall magmatic-hydrothermal system and, thus, develops vectors towards the magmatic center of the system that is most likely to host economic mineralization.

Tourmaline boron and strontium isotope systematics reveal magmatic fluid pulses and external fluid influx in a giant iron oxide-apatite (IOA) deposit

Tourmaline is a common boron-bearing mineral in hydrothermal system and has been widely used as a mineral probe to reconstruct geological processes because of its broad range in composition and resistance to metasomatic alteration. The origin of Kiruna-type iron oxide-apatite (IOA) deposits, commonly linked to andesitic subvolcanic or volcanic rocks, is highly controversial. Constraints on the evolution of these mineralizing systems are needed to advance understanding of the ore-forming process. In this study, we apply in situ elemental and combined B-Sr isotopic analyses of tourmaline to elucidate the nature and evolution of the subsurface hydrothermal system associated with IOA mineralization in the giant Taocun deposit, eastern China. Taocun is hosted at the top of a diorite intrusion and exhibits three stages of hydrothermal alteration that contain tourmaline: pre-ore Na alteration (Tur I), syn-ore magnetite formation and associated Ca-Fe alteration (Tur II), and post-ore Ca-Mg alteration with sulfide veins (Tur III). Compositional data for each stage of tourmaline plot along the “oxy-dravite”–povondraite join, which is indicative of precipitation from relatively oxidizing fluids. Ranges of Sr-isotopic compositions in Tur I (0.7065–0.7078) and Tur II (0.7068–0.7076) are identical to those of the igneous host rocks, indicating precipitation from magmatic-hydrothermal fluids. The range of B-isotopic compositions in Tur I (δ 11 B values of −6.3‰ to −1.2‰) is also consistent with a magmatic source. Higher δ 11 B values (−2.4‰ to 5.4‰) obtained from Tur II are mainly ascribed to Rayleigh fractionation in the magmatic-hydrothermal system as tourmaline precipitated. Post-ore Tur III has a wide range of mostly lower B-isotopic compositions (−8.5‰ to 0.8‰) that record another pulse of magmatic fluid input. This interpretation is supported by the enrichment of Na, Li, Be, W, Sn, V, and Ti in Tur III, relative to Tur I and II. However, the higher Sr-isotope composition (0.7076–0.7086) of Tur III and available O-isotope composition (−7‰ to 3.5‰) of fluids of this stage record the infiltration of meteoric ground water from adjacent sedimentary country rocks. The results suggest that the Taocun IOA deposit formed in a magmatic-hydrothermal system characterized by two (or more) pulses of magmatic fluid discharge from subvolcanic diorite intrusions, followed by the influx of external ground water as the system waned. This study highlights the utility of tourmaline as a robust geochemical and isotopic monitor of ore-forming processes in such systems.

Geochronology and geochemistry of the Dianfang gold deposit, western Henan Province, central China: Implications for mineral exploration

The Dianfang gold deposit, located in the Xiong’ershan–Waifangshan region within the southern margin of the North China Craton, consists of eastern and western ore blocks, which are hosted in the Dianfang breccia pipe and Paleoproterozoic volcanic rocks, respectively. The eastern ore block, which occurs within the southern and hanging wall margins of the Dianfang breccia pipe and in fractures in the rhyolites of the Jidanping Formation, consists of rhyolite-hosted and breccia-hosted disseminated gold mineralization structurally controlled by ENE-striking faults. The western ore block contains gold-bearing quartz-sulfide veins and minor disseminated rhyolite-hosted gold mineralization that occurs in the annular fractures around the Hougou breccia pipe. The two ore blocks have long been researched and prospected as two different genetic types. Detailed fieldwork and microscopic observations reveal that the eastern and western ore blocks contain the same hydrothermal alteration and mineral assemblages, which include K-feldspar, quartz, sericite, chlorite, epidote, carbonate, pyrite, galena, sphalerite, marcasite and chalcopyrite, as well as minor magnetite, anatase, cervelleite, matildite, and bismuthinite. Gold occurs as electrum inclusions in pyrite or along microfractures in sulfides and quartz. Zircon U–Pb geochronology of the granite porphyry around the Hougou breccia pipe constrains the timing of breccia pipe formation to 145.9 Ma which is consistent with the formation age of the Dianfang breccia pipe (145.8 Ma), indicating that the two breccia pipes formed coevally at the end of the late Jurassic, rather than during the Paleoproterozoic, as was suggested by previous studies. The hydrothermal sulfides from the main orebody yield a Rb–Sr isochron age of 119.5 ± 1.8 Ma, suggesting that the eastern and western ore blocks formed coevally at the end of the early Cretaceous. In situ mineral trace element data, as well as sulfur and lead isotope data suggest that the eastern and western ore blocks were formed by a common ore-forming fluid that evolved from a magmatic-hydrothermal system that was genetically related to a hidden late Mesozoic granite. Pre-existing fractures and breccia then served as ideal conduits for fluid flow, accumulation, and gold deposition. Consequently, we propose that the ENE-striking faults developed in and around the breccia pipes and the annular brittle faults around the breccia pipes are good targets for future gold exploration at the Dianfang gold deposit. Based on these results and data from other gold deposits of similar ages around the margins of the North China Craton, we argue that the gold deposits in Xiong’ershan region formed under conditions of lithospheric extension from the late Jurassic to the early Cretaceous, which resulted from lithospheric thinning due to the westward subduction of the Pacific Plate.

Footprints of element mobility during metasomatism linked to a late Miocene peraluminous granite intruding a carbonate host (Campiglia Marittima, Tuscany)

The Campiglia Marittima magmatic-hydrothermal system includes a peraluminous granite, its carbonatic host, and skarn. The system evolved generating a time-transgressive exchange of major and trace elements between granite, metasomatic fluids, and host rock. The process resulted in partial metasomatic replacement of the granite and severe replacement of the carbonate host rocks. The fluid activity started during a late-magmatic stage, followed by a potassic–calcic metasomatism, ending with a lower temperature acidic metasomatism. During the late-magmatic stage, B-rich residual fluids led to the formation of disseminated tourmaline–quartz orbicules. High-temperature metasomatic fluids generated a pervasive potassic–calcic metasomatism of the granite, with replacement of plagioclase, biotite, ilmenite, and apatite by K-feldspar, phlogopite–chlorite–titanite, titanite–rutile, and significant mobilization of Fe, Na, P, Ti, and minor HFSE/REE. The metasomatized granite is enriched in Mg, K, Rb, Ba, and Sr, and depleted in Fe and Na. Ca metasomatism is characterized by crystallization of a variety of calc-silicates, focusing along joints into the granite (endoskarn) and at the marble/pluton contact (exoskarn), and exchange of HFSE and LREE with hydrothermal fluids. Upon cooling, fluids became more acidic and fluorine activity increased, with widespread crystallization of fluorite from disequilibrium of former calc-silicates. At the pluton-host boundary, fluids were accumulated, and pH buffered to low values as temperature decreased, leading to the formation of a metasomatic front triggering the increasing mobilization of REE and HFSE and the late crystallization of REE–HFSE minerals.

Distribution of radon and risk assessment of its radiation dose in groundwater drinking for village people nearby the W-polymetallic metallogenic district at Dongpo in southern Hunan province, China

Radon in the household water (especially groundwater) which is an important source of indoor radon, has become a potential health hazard to residents. In this study, radon concentrations in groundwater sampled from five villages near Dongpo W-polymetallic metallogenic region were measured using RAD-7 detector with RAD H2O accessory, and the effect of regional geology and mineralization on radon concentration in groundwater was studied. In addition, we also estimated the radiation doses received by people via ingestion of radon in water and inhalation of the radon from the indoor air while using water. The results show that the radon concentration in groundwater samples varies from 1.29 Bq L−1 to 31.31 Bq L−1 with 10.47 Bq L−1 on average, and about 31.3% of the groundwater samples analyzed have a higher radon concentration than the maximum contaminant level of 11.1 Bq L−1 recommended by United States Environmental Protection Agency (USEPA). The relatively high radon level in groundwater can be attributed to a relatively high uranium background produced by the magmatic activity and magmatic-hydrothermal system. The values of annual effective dose (AEDing) due to ingestion of radon in groundwater range from 0.002 mSv y−1 to 0.055 mSv y−1, 0.005 mSv y−1 to 0.11 mSv y−1 and 0.008 mSv y−1 to 0.188 mSv y−1 for adult, child and infant respectively. The values of annual effective dose due to the inhalation of radon released from water are 63.6, 15.4 and 3.8 times of those through the ingestion of radon in groundwater by the adults, children and infants, respectively. In addition, the values of estimated total annual effective doses are 0.020–0.480 mSv y−1, 0.017–0.406 mSv y−1 and 0.020–0.484 mSv y−1 for adult, child and infant, respectively. These values are much lower than the reference dose level of 1 mSv y−1 recommended by World Health Organization (WHO) and United Nations Scientific Committee on the Effect of Atomic Radiation (UNSCEAR).

Magmatic-hydrothermal transition of Mo-W-mineralized granite-pegmatite-greisen system recorded by trace elements in quartz: Krupka district, Eastern Krušné hory/Erzgebirge

Magmatic-hydrothermal transition of highly evolved granitic melts enriched in volatile and incompatible elements can involve disequilibrium intermediate products between aluminosilicate melt and hydrothermal fluid (hydrosilicate liquids) with high ore-forming potential. We investigate evolution from Li-F-rich granites through pegmatites, greisens and quartz veins in a composite stock at Knöttel in the Krupka district (eastern Krušné hory/Erzgebirge mountain range) by monitoring trace-element variations in quartz. Interelemental correlations reveal Si4+ ↔ Li+Al3+ and likely Si4+ ↔ H+Al3+ to be the most important substitution mechanisms. Variations in Ti vs. Li, Be and Al define distinct evolutionary trends: (i) magmatic, high-Li/Ti or Al/Ti trend (granites – aplites – K-feldspar pegmatite); (ii) transitional, medium-Li/Ti trend (quartz megacrysts and pegmatite lenses in granite – quartz-protolithionite pegmatite); (iii) hydrothermal, low-Li/Ti or Al/Ti trend (stockwork of coarse-grained hydrothermal quartzites and quartz veins, quartz replacement in greisens). The medium-Li/Ti trend represents hydrosilicate liquid, an H2O- and SiO2-rich medium with low density and effective viscosity that was probably formed during disequilibrium crystallization in front of rapidly propagating solidification front. Thermal evolution of the magmatic-hydrothermal system was monitored by Ti-in-quartz thermometry. Calculated rutile activity of the granites is very low (0.3–0.05) but it increases (up to 1, that is, saturation) towards pegmatites and hydrothermal veins. Magmatic crystallization (granites and aplites) is constrained to 700–580 °C, pegmatite and bulk greisenization stage occurred at 600–500 °C, followed by a late hydrothermal stage associated with the formation of distal quartz veins at 500–390 °C. The granite-pegmatite systems at Knöttel and in Erzgebirge in general reach extremely high Al, Li, Rb and Ge and low Ti concentrations in quartz in comparison with igneous rocks worldwide. The Knöttel stock belongs to P-poor A-type granites in the Erzgebirge and is linked with them by similar evolutionary trends in quartz trace elements. Furthermore, the Knöttel system exhibits Be enrichment in quartz (probably related to high contents of F) and this appears to be typical feature of Mo-W-mineralized systems in general. The hydrothermal phase with Mo-W mineralization at Knöttel is closely related to the magmatic phase of parental granite body, which seems to be an important condition for Mo-W-mineralization formation.

Geochemical, stable isotopic (S, O, H, C), microthermometric and geochronological (U-Pb) evidence on the genesis of the Pınarbaşı porphyry Cu-Mo mineralization (Gediz-Kütahya, Western Turkey)

The Pınarbaşı porphyry CuMo mineralization is located at northwest of Gediz (Kütahya-Turkey) and east of Simav (Kütahya-Turkey) in western Anatolia. The Pınarbaşı CuMo mineralization is hosted by Pınarbaşı granitoidic intrusion consisting of granite, granodiorite and quartz monzonite. Geochemical and geochronological evidences for Pınarbaşı granitoidic rocks show that they are high-K calc-alkaline, and I-type granitoid magma likely developed post-collisional extensional regime. The UPb zircon age of granite (18.88 ± 0.17 Ma) and quartz monzonite porphyry (18.27 ± 0.14) obtained from the Pınarbaşı granitoid show Early Miocene (Burdigalian). The Pınarbaşı CuMo mineralization predominantly comprises molybdenite, chalcopyrite, galena, sphalerite, pyrite, fahlore, magnetite, bornite, hematite, jarosite, malachite and orpiment occurred in disseminated form in veins/veinlets associated with potassic, phyllic (sericitic) and advanced argillic alteration zones. According to the paragenetic and crosscutting relationships of veins/veinlets, the ore-forming process were divided into three stages; early-stage: quartz – molybdenite ± K-feldspar ± pyrite veins associated with potassic alteration, middle-stage: quartz ± calcite ± chalcopyrite ± galena ± sphalerite ± molybdenite + pyrite veins in phyllic alteration and late-stage: quartz ± calcite ± pyrite veins associated with advanced argillic alteration. Three types of fluid inclusions in quartz distinguished were designated as L-rich L + V phases (Type-I), salt-bearing L + V + S (Type-II), and V-rich L + V phases (Type-III). FIs of the early and middle stages are predominantly Type-II and Type-III inclusions, whereas the late-stage minerals commonly contain Type-I inclusions. Homogenization temperatures and salinities of FIs trapped in the early-stage quartz range from 481 to 590 °C and 13.19 to 61.1 wt% NaCl equivalent, respectively. FIs in quartz of the middle-stage yield homogenization temperatures (Th) of 310 to 460 °C, while halite dissolution temperatures are ranged from 264 to 430 °C, and salinities of 7.9 to 50.3 wt% NaCl eq. Homogenization temperatures and salinities of FIs in calcite of the middle-stage are range from 270 to 420 °C, 3.4 to 49.1 wt% NaCl eq. The late-stage homogenize at temperatures of 138 to 240 °C, and salinities of 0.9 to 6.5 wt% NaCl eq. The δ34SH2S values (0.6 to 4.5‰) of sulfides (molybdenite, chalcopyrite, pyrite and galena) and the δ18OSMOW (6.9 to 9.6‰) - δD (−71 to −86‰) values of molybdenite-bearing quartz from Pınarbaşı CuMo mineralization suggest a magmatic origin for the ore-forming fluids. The δ13CPDB (from −4.65‰ to 0.55‰) and δ18OSMOW (from 9.05‰ to 18.76‰) values of calcite which is one of the most common gangue minerals in Pınarbaşı mineralization show a high temperature influence and/or sedimentary contamination process to magmatic carbonate as well as continental carbonate. The S–O–H–C and UPb isotopic compositions indicate that the metallic elements and fluids came primarily from a magmatic source linked to Miocene intrusion. The geological, geochronological, and geochemical data support a magmatic-hydrothermal origin for the Pınarbaşı CuMo mineralization and confirm that mineralization is formed from an Early Miocene porphyry-related magmatic-hydrothermal system that is genetically linked with Eğrigöz and Pınarbaşı granitoids.