Journal articles: 'Magmatic Volatiles'

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De Vivo, B., A. Lima, and J. D. Webster. "Volatiles in Magmatic-Volcanic Systems." Elements 1, no. 1 (January 1, 2005): 19–24. http://dx.doi.org/10.2113/gselements.1.1.19.

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Degruyter, Wim, Andrea Parmigiani, Christian Huber, and Olivier Bachmann. "How do volatiles escape their shallow magmatic hearth?" Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, no. 2139 (January 7, 2019): 20180017. http://dx.doi.org/10.1098/rsta.2018.0017.

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Only a small fraction (approx. 1–20%) of magmas generated in the mantle erupt at the surface. While volcanic eruptions are typically considered as the main exhaust pipes for volatile elements to escape into the atmosphere, the contribution of magma reservoirs crystallizing in the crust is likely to dominate the volatile transfer from depth to the surface. Here, we use multiscale physical modelling to identify and quantify the main mechanisms of gas escape from crystallizing magma bodies. We show that most of the outgassing occurs at intermediate to high crystal fraction, when the system has reached a mature mush state. It is particularly true for shallow volatile-rich systems that tend to exsolve volatiles through second boiling, leading to efficient construction of gas channels as soon as the crystallinity reaches approximately 40–50 vol.%. We, therefore, argue that estimates of volatile budgets based on volcanic activity may be misleading because they tend to significantly underestimate the magmatic volatile flux and can provide biased volatile compositions. Recognition of the compositional signature and volumetric dominance of intrusive outgassing is, therefore, necessary to build robust models of volatile recycling between the mantle and the surface. This article is part of the Theo Murphy meeting issue ‘Magma reservoir architecture and dynamics’.

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Day, James M. D., Frédéric Moynier, and Charles K. Shearer. "Late-stage magmatic outgassing from a volatile-depleted Moon." Proceedings of the National Academy of Sciences 114, no. 36 (August 21, 2017): 9547–51. http://dx.doi.org/10.1073/pnas.1708236114.

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The abundance of volatile elements and compounds, such as zinc, potassium, chlorine, and water, provide key evidence for how Earth and the Moon formed and evolved. Currently, evidence exists for a Moon depleted in volatile elements, as well as reservoirs within the Moon with volatile abundances like Earth’s depleted upper mantle. Volatile depletion is consistent with catastrophic formation, such as a giant impact, whereas a Moon with Earth-like volatile abundances suggests preservation of these volatiles, or addition through late accretion. We show, using the “Rusty Rock” impact melt breccia, 66095, that volatile enrichment on the lunar surface occurred through vapor condensation. Isotopically light Zn (δ66Zn = −13.7‰), heavy Cl (δ37Cl = +15‰), and high U/Pb supports the origin of condensates from a volatile-poor internal source formed during thermomagmatic evolution of the Moon, with long-term depletion in incompatible Cl and Pb, and lesser depletion of more-compatible Zn. Leaching experiments on mare basalt 14053 demonstrate that isotopically light Zn condensates also occur on some mare basalts after their crystallization, confirming a volatile-depleted lunar interior source with homogeneous δ66Zn ≈ +1.4‰. Our results show that much of the lunar interior must be significantly depleted in volatile elements and compounds and that volatile-rich rocks on the lunar surface formed through vapor condensation. Volatiles detected by remote sensing on the surface of the Moon likely have a partially condensate origin from its interior.

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Persikov, Edward S., Vilen A. Zharikov, and Pavel G. Bukhtiyarov. "The effect of volatiles on the properties of magmatic melts." European Journal of Mineralogy 2, no. 5 (October 4, 1990): 621–42. http://dx.doi.org/10.1127/ejm/2/5/0621.

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5

Kusakabe, Minoru, and Hiroshi Shinohara. "Matsuo Memorial Issue: Magmatic Volatiles and Volcanic Discharges Preface." GEOCHEMICAL JOURNAL 27, no. 4-5 (1993): 181–83. http://dx.doi.org/10.2343/geochemj.27.181.

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Zolotov, Mikhail Yu. "On the chemistry of mantle and magmatic volatiles on Mercury." Icarus 212, no. 1 (March 2011): 24–41. http://dx.doi.org/10.1016/j.icarus.2010.12.014.

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7

Zhao, Rongsheng, Xuanlong Shan, Jian Yi, Ye Liang, Chunlong Li, and Cuiying Qiu. "Understanding fluid behavior through ion and isotope data from the Yitong Basin, Northeast China." Canadian Journal of Earth Sciences 55, no. 3 (March 2018): 308–20. http://dx.doi.org/10.1139/cjes-2017-0154.

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To evaluate ion origins and fluid behavior, the chemical properties of thermal water sampled from the Eocene reservoir in the Yitong Basin (YB), Northeast China, were investigated. The thermal water samples are classified as Na–HCO3-type water and were fully equilibrated, except for Sijixiangkang (SJXK) and Yitong (YT). The cations originate mainly from water–rock interactions (e.g., albitization and weathering of plagioclase), while the anions originate from magmatic volatiles and leaching of limestone and granite, which were heated by hot magmatic volatiles and exhibited an evaporation-like pattern in the Gibbs diagrams. The existence of magmatic volatiles was verified by the high ion ratio, the minor-element origins, δ13C values of HCO3, and δ34S values of SO4, which flowed upward along lithospheric faults, with higher fluxes in the northeast than in the southwest (the δ13C value of the Chaluhe depression (CD) is 0.93‰ lower than that of the Moliqing depression (MD, 1.63‰)). Furthermore, according to the Br/Cl and HCO3−/Cl ratios and the δ13C values, we speculate that a deep Permian limestone reservoir exists below the granitic unit. Based on the ion origins and fluid potentials, we conclude that the CD and MD are open systems rather than closed systems. The recharged water migrates from the margin to the center in the plane, and in the vertical direction, it migrates from the Yongji (E2y) and Sheling (E2sh) strata to the overlying strata and underlying Shuangyang (E2s) strata along faults. By summarizing all of the available data, we proposed a conceptual model of fluid migration.

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Barnes, Jessica J., Mahesh Anand, and Ian A. Franchi. "Investigating the History of Magmatic Volatiles in the Moon Using NanoSIMS." Microscopy and Microanalysis 22, S3 (July 2016): 1804–5. http://dx.doi.org/10.1017/s1431927616009867.

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9

Schiavi, F., N. Bolfan-Casanova, R. Buso, M. Laumonier, D. Laporte, K. Medjoubi, S. Venugopal, A. Gómez-Ulla, N. Cluzel, and M. Hardiagon. "Quantifying magmatic volatiles by Raman microtomography of glass inclusion-hosted bubbles." Geochemical Perspectives Letters 16 (December 2020): 17–24. http://dx.doi.org/10.7185/geochemlet.2038.

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Mikhailova, Julia A., Yakov A. Pakhomovsky, Olga F. Goychuk, Andrey O. Kalashnikov, Ayya V. Bazai, and Victor N. Yakovenchuk. "Pre-Pegmatite Stage in Peralkaline Magmatic Process: Insights from Poikilitic Syenites from the Lovozero Massif, Kola Peninsula, Russia." Minerals 11, no. 9 (September 7, 2021): 974. http://dx.doi.org/10.3390/min11090974.

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The Lovozero peralkaline massif (Kola Peninsula, Russia) is widely known for its unique mineral diversity, and most of the rare metal minerals are found in pegmatites, which are spatially associated with poikilitic rocks (approximately 5% of the massif volume). In order to determine the reasons for this relationship, we have investigated petrography and the chemical composition of poikilitic rocks as well as the chemical composition of the rock-forming and accessory minerals in these rocks. The differentiation of magmatic melt during the formation of the rocks of the Lovozero massif followed the path: lujavrite → foyaite → urtite (magmatic stage) → pegmatite (hydrothermal stage). Yet, for peralkaline systems, the transition between magmatic melt and hydrothermal solution is gradual. In the case of the initially high content of volatiles in the melt, the differentiation path was probably as follows: lujavrite → foyaite (magmatic stage) → urtitization of foyaite → pegmatite (hydrothermal stage). Poikilitic rocks were formed at the stage of urtitization, and we called them pre-pegmatites. Indeed, the poikilitic rocks have a metasomatic texture and, in terms of chemical composition, correspond to magmatic urtite. The reason for the abundance of rare metal minerals in pegmatites associated with poikilitic rocks is that almost only one nepheline is deposited during urtitization, whereas during the magmatic crystallization of urtite, rare elements form accessory minerals in the rock and are less concentrated in the residual solution.

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11

Wallace, Paul J., Simon A. Cam, William I. Rose, Gregg J. S. Bluth, and Terry Gerlach. "Integrating petrologic and remote sensing perspectives on magmatic volatiles and volcanic degassing." Eos, Transactions American Geophysical Union 84, no. 42 (2003): 441. http://dx.doi.org/10.1029/2003eo420001.

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12

Zhang, Mingjie, Pengyu Feng, Tong Li, Liwu Li, Juerong Fu, Peng Wang, Yuekun Wang, Zhongping Li, and Xiaodong Wang. "The Petrogenesis of the Permian Podong Ultramafic Intrusion in the Tarim Craton, Western China: Constraints from C-He-Ne-Ar Isotopes." Geofluids 2019 (August 22, 2019): 1–14. http://dx.doi.org/10.1155/2019/6402571.

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The Podong Permian ultramafic intrusion is only one ultramafic intrusion with massif Ni-Cu sulfide mineralization in the Pobei layered mafic-ultramafic complex, western China. It is obviously different in sulfide mineralization from the nearby coeval Poyi ultramafic intrusion with the largest disseminated Ni-Cu sulfide mineralization and mantle plume contribution (Zhang et al., 2017). The type and addition mechanism of the confirmed crustal contaminations and possible mantle plume involved in the intrusion formation require evidences from carbon and noble gas isotopic compositions. In the present study, we have measured C, He, Ne, and Ar isotopic compositions of volatiles from magmatic minerals in the Podong ultramafic intrusion. The results show that olivine, pyroxene, and plagioclase minerals in the Podong intrusion have variable δ13C of CO2 (-24.5‰ to -3.2‰). The CH4, C2H6, C3H8, and C4H10 hydrocarbon gases show normal or partial reversal distribution patterns of carbon isotope with carbon number and light δ13C1 value of CH4, indicating the hydrocarbon gases of biogenic origin. The δ13C of CO2 and CH4 suggested the magmatic volatile of the mantle mixed with the volatiles of thermogenic and crustal origins. Carbon and noble gas isotopes indicated that the Podong intrusion could have a different petrogenesis from the Poyi ultramafic intrusion. Two types of contaminated crustal materials can be identified as crustal fluids from subducted altered oceanic crust (AOC) in the lithospheric mantle source and a part of the siliceous crust. The carbon isotopes for different minerals show that magma spent some time crystallizing in a magma chamber during which assimilation of crustal material occurred. Subduction-devolatilization of altered oceanic crust could be the best mechanism that transported large proportion of ASF (air-saturated fluid) and crustal components into the mantle source. The mantle plume existing beneath the Poyi intrusion could provide less contribution of real materials of silicate and fluid components.

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Seewald, Jeffrey S., Eoghan P. Reeves, Wolfgang Bach, Peter J. Saccocia, Paul R. Craddock, Wayne C. Shanks, Sean P. Sylva, Thomas Pichler, Martin Rosner, and Emily Walsh. "Submarine venting of magmatic volatiles in the Eastern Manus Basin, Papua New Guinea." Geochimica et Cosmochimica Acta 163 (August 2015): 178–99. http://dx.doi.org/10.1016/j.gca.2015.04.023.

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14

Wang, Shuai, and Sen Hu. "Hydrogen Isotopic Variations in the Shergottites." Geosciences 10, no. 4 (April 17, 2020): 148. http://dx.doi.org/10.3390/geosciences10040148.

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Hydrogen isotopes in the shergottite Martian meteorites are among the most varied in Mars laboratory samples. By collating results of previous studies on major hydroxyl, deuterium, and H2O bearing phases, we provide a compendium of recent measurements in order to elucidate crustal-rock versus mantle-rock processes on Mars. We summarize recent works on volatile and δD measurements in a range of shergottite phases: from melt inclusions, apatite, merrillite, maskelynite, impact melt glass, groundmass glass, and nominal anhydrous minerals. We interpret these observations using an evidence-based approach, considering two particular scenarios: (1) water-rock crustal interactions versus (2) magmatic-based processes. We consider the implications of these measurements and the scope they have for future studies, paying particular attention to future works on H, S, and Cl isotopes in situ, shedding light on the nature of volatiles in the hydrosphere and lithosphere of Mars.

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15

Yao, Zhuosen, James E. Mungall, and Kezhang Qin. "A Preliminary Model for the Migration of Sulfide Droplets in a Magmatic Conduit and the Significance of Volatiles." Journal of Petrology 60, no. 12 (December 1, 2019): 2281–316. http://dx.doi.org/10.1093/petrology/egaa005.

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Abstract A close relationship between Ni–Cu–(PGE) sulfide deposits and magmatic conduit systems has been widely accepted, but our present understanding still rests on empirical inductions that sulfide liquids are entrained during magma ascent and aggregated at hydrodynamic traps such as the opening of a conduit into a larger magma body. In this contribution, a preliminary quantitative model for the dynamics of mm-scale sulfide droplets in a vertical magmatic conduit is developed, examining such limiting parameters as the size, transport velocity and the magmas’ maximum carrying capacity for sulfide droplets. Addition of numerous dense sulfide droplets significantly reduces magma buoyancy and rapidly increases the bulk viscosity, and the resulting pressure gradient in the propagating conduit dyke restricts the maximum volume fraction of droplets that can be carried by ascending magma. For sulfide droplets alone, the maximum carrying capacity is low, but it will be improved dramatically by the addition of volatiles which reduces the density and viscosity of silicate melt. Potential volatile degassing during decompression further facilitates sulfide entrainment by reducing bulk magma density, and the formation of buoyant compound vapour-sulfide liquid bubble drops also greatly enhances the carrying capacity. The breakdown of compound drops by detachment of parts of the vapour bubble or sulfide droplet may occur at low pressure, which liberates sulfide liquids from rising compound drops, potentially to collect in traps in the conduit system. When sulfide-laden magma flows through a widening conduit, many droplets can be captured by the re-circulation flow just downstream of the expanding section, followed by sulfide liquid accumulation and enhanced chemical interaction via diffusive exchange with the recirculating magma, potentially resulting in an economic, high-tonnage ore body. We apply our models to the emplacement of sulfide-rich magmatic suspensions at Noril’sk and show that the disseminated mineralization in intrusions could have formed when magmas carrying re-suspended sulfide liquid entrained from pre-existing sulfide accumulations in the conduit system reached their limiting sulfide carrying capacity as dictated by buoyancy and were deflected into blind sills flanking the principal conduit for flood basalt volcanism.

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Lowenstern, J. B. "A review of the contrasting behavior of two magmatic volatiles: chlorine and carbon dioxide." Journal of Geochemical Exploration 69-70 (June 2000): 287–90. http://dx.doi.org/10.1016/s0375-6742(00)00075-3.

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Kelley, Katherine A., and Elizabeth Cottrell. "Water and the Oxidation State of Subduction Zone Magmas." Science 325, no. 5940 (July 30, 2009): 605–7. http://dx.doi.org/10.1126/science.1174156.

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Mantle oxygen fugacity exerts a primary control on mass exchange between Earth’s surface and interior at subduction zones, but the major factors controlling mantle oxygen fugacity (such as volatiles and phase assemblages) and how tectonic cycles drive its secular evolution are still debated. We present integrated measurements of redox-sensitive ratios of oxidized iron to total iron (Fe3+/ΣFe), determined with Fe K-edge micro–x-ray absorption near-edge structure spectroscopy, and pre-eruptive magmatic H2O contents of a global sampling of primitive undegassed basaltic glasses and melt inclusions covering a range of plate tectonic settings. Magmatic Fe3+/ΣFe ratios increase toward subduction zones (at ridges, 0.13 to 0.17; at back arcs, 0.15 to 0.19; and at arcs, 0.18 to 0.32) and correlate linearly with H2O content and element tracers of slab-derived fluids. These observations indicate a direct link between mass transfer from the subducted plate and oxidation of the mantle wedge.

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Callegaro, Sara, Kalotina Geraki, Andrea Marzoli, Angelo De Min, Victoria Maneta, and Don R. Baker. "The quintet completed: The partitioning of sulfur between nominally volatile-free minerals and silicate melts." American Mineralogist 105, no. 5 (May 1, 2020): 697–707. http://dx.doi.org/10.2138/am-2020-7188.

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Abstract Magmatic systems are dominated by five volatiles, namely H2O, CO2, F, Cl, and S (the igneous quintet). Multiple studies have measured partitioning of four out of these five volatiles (H2O, CO2, F, and Cl) between nominally volatile-free minerals and melts, whereas the partitioning of sulfur is poorly known. To better constrain the behavior of sulfur in igneous systems we measured the partitioning of sulfur between clinopyroxene and silicate melts over a range of pressure, temperature, and melt composition from 0.8 to 1.2 GPa, 1000 to 1240 °C, and 49 to 66 wt% SiO2 (13 measurements). Additionally, we determined the crystal-melt partitioning of sulfur for plagioclase (6 measurements), orthopyroxene (2 measurements), amphibole (2 measurements), and olivine (1 measurement) in some of these same run products. Experiments were performed at high and low oxygen fugacities, where sulfur in the melt is expected to be dominantly present as an S6+ or an S2– species, respectively. When the partition coefficient is calculated as the total sulfur in the crystal divided by the total sulfur in the melt, the partition coefficient varies from 0.017 to 0.075 for clinopyroxene, from 0.036 to 0.229 for plagioclase, and is a maximum of 0.001 for olivine and of 0.003 for orthopyroxene. The variation in the total sulfur partition coefficient positively correlates with cation-oxygen bond lengths in the crystals; the measured partition coefficients increase in the order: olivine < orthopyroxene < clinopyroxene ≤ amphibole and plagioclase. At high oxygen fugacities in hydrous experiments, the clinopyroxene/melt partition coefficients for total sulfur are only approximately one-third of those measured in low oxygen fugacity, anhydrous experiments. However when the partition coefficient is calculated as total sulfur in the crystal divided by S2– in the melt, the clinopyroxene/melt partition coefficients for experiments with melts between ~51 and 66 wt% SiO2 can be described by a single mean value of 0.063 ± 0.010 (1σ standard deviation about the mean). These two observations support the hypothesis that sulfur, as S2–, replaces oxygen in the crystal structure. The results of hydrous experiments at low oxygen fugacity and anhydrous experiments at high oxygen fugacity suggest that oxygen fugacity has a greater effect on sulfur partitioning than water. Although the total sulfur clinopyroxene-melt partition coefficients are affected by the Mg/(Mg+Fe) ratio of the crystal, partition coefficients calculated using S2– in the melt display no clear dependence upon the Mg# of the clinopyroxene. Both the bulk and the S 2– partition coefficients appear unaffected by IVAl in the clinopyroxene structure. No effect of anorthite content nor of iron concentration in the crystal was seen in the data for plagioclase-melt partitioning. The data obtained for orthopyroxene and olivine were too few to establish any trends. The partition coefficients of total sulfur and S 2– between the crystals studied and silicate melts are typically lower than those of fluorine, higher than those of carbon, and similar to those of chlorine and hydrogen. These sulfur partition coefficients can be combined with analyses of volatiles in nominally volatile-free minerals and previously published partition coefficients of H2O, C, F, and Cl to constrain the concentration of the igneous quintet, the five major volatiles in magmatic systems.

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Jentsch, Anna, Egbert Jolie, David G. Jones, Helen Taylor-Curran, Loïc Peiffer, Martin Zimmer, and Bob Lister. "Magmatic volatiles to assess permeable volcano-tectonic structures in the Los Humeros geothermal field, Mexico." Journal of Volcanology and Geothermal Research 394 (April 2020): 106820. http://dx.doi.org/10.1016/j.jvolgeores.2020.106820.

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Bailey, D. K., and J. D. Collier. "Carbonatite-melilitite association in the Italian collision zone and the Ugandan rifted craton: significant common factors." Mineralogical Magazine 64, no. 4 (August 2000): 675–82. http://dx.doi.org/10.1180/002646100549698.

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AbstractItalian carbonatites form part of a suite with melilitites, normally an association characteristic of continental interiors; the perfect analogue of the Italian suite being the kamafugites (from the type area in SW Uganda, where the western branch of the East African Rift Zone cuts across the craton). The latter are commonly attributed to plume generation, whereas the Italian carbonatites, strung along the Appennine front, are usually linked to subduction. Evidently these two mechanisms are not essential, since neither can apply in both provinces. This conclusion is re-inforced by the related magmatism registered in both provinces in the Cretaceous. Phlogopite is ubiquitous in the mantle debris, and compositions from the two provinces overlap. Xenolithic phlogopites are distinct from cognate micas in the lavas, and from the carrier melt compositions, with similar distribution patterns in both suites. Kamafugitic magmas must be products of exceptional conditions, and added to the many near-identical magmatic features, the Italian and Ugandan volcanoes have sampled similar mantle conditions. Although the large scale geodynamic regimes are in total contrast, as are the deep mantle tomographic structures, the crucial common factor at the igneous province level is extensional tectonics. Extension, promoting release of volatiles (esp. CO2), is the vital trigger for this small volume, primary magmatism.

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Reavy, R. J., D. H. W. Hutton, and A. A. Finch. "The nodular granite of Castanheira, north central Portugal: origin of the nodules and evidence for diapiric mobilization of granite." Geological Magazine 130, no. 2 (March 1993): 145–53. http://dx.doi.org/10.1017/s001675680000981x.

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AbstractThe Castanheira pluton in north-central Portugal is a small (1000 m × 600 m) granite body of Hercynian age which contains a remarkable abundance of granite-cored, biotite-rimmed nodules. The nodules are interpreted as representing original bubbles in the uppermost volatile-rich zone of a granitic pluton. Strong depletion in K and Rb in the host granite around the nodules suggests that the biotite is magmatic in origin. The nodules may have formed by reaction between chloroferrate(II) complexes in the vapour phase and silicate melt, possibly followed by condensation of the vapour phase to a small granitic core. Motion of the vapour bubble stabilized a gradient in chemical potential with respect to the host granite, giving rise to the nodules. Chemical, petrological and structural data suggest that the pluton was part of a larger granite body, which was forcefully emplaced during synchronous transcurrent shearing. The inferred presence of volatiles, in addition to the pervasive tourmalinization of the roof zone, suggest that the magma was halogen-rich; this may imply that the magma had low viscosity.

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Yin, Rong, Li Han, Xiao-Long Huang, Jie Li, Wu-Xian Li, and Lin-Li Chen. "Textural and chemical variations of micas as indicators for tungsten mineralization: Evidence from highly evolved granites in the Dahutang tungsten deposit, South China." American Mineralogist 104, no. 7 (July 1, 2019): 949–65. http://dx.doi.org/10.2138/am-2019-6796.

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Abstract The Dahutang tungsten deposit, located in the Yangtze Block, South China, is one of the largest tungsten deposits in the world. Tungsten mineralization is closely related to Mesozoic granitic plutons. A drill core through a pluton in the Dalingshang ore block in the Central segment of the Dahutang tungsten deposit shows that the pluton is characterized by multi-stage intrusive phases including biotite granite, muscovite granite, and Li-mica granite. The granites are strongly peraluminous and rich in P and F. Decreasing bulk-rock (La/Yb)N ratios and total rare earth element (ΣREE) concentrations from the biotite granite to muscovite granite and Li-mica granite suggest an evolution involving the fractional crystallization of plagioclase. Bulk-rock Li, Rb, Cs, P, Sn, Nb, and Ta contents increase with decreasing Zr/Hf and Nb/Ta ratios, denoting that the muscovite granite and Li-mica granite have experienced a higher degree of magmatic fractionation than the biotite granite. In addition, the muscovite and Li-mica granites show M-type lanthanide tetrad effect, which indicates hydrothermal alteration during the post-magmatic stage. The micas are classified as lithian biotite and muscovite in the biotite granite, muscovite in the muscovite granite, and Li-muscovite and lepidolite in the Li-mica granite. The Li, F, Rb, and Cs contents of micas increase, while FeOT, MgO, and TiO2 contents decrease with increasing degree of magmatic fractionation. Micas in the muscovite granite and Li-mica granite exhibit compositional zonation in which Si, Rb, F, Fe, and Li increase, and Al decreases gradually from core to mantle, consistent with magmatic differentiation. However, the outermost rim contains much lower contents of Si, Rb, F, Fe, and Li, and higher Al than the mantle domains due to metasomatism in the presence of fluids. The variability in W contents of the micas matches the variability in Li, F, Rb, and Cs contents, indicating that both the magmatic and hydrothermal evolutions were closely associated with W mineralization in the Dahutang deposit. The chemical zoning of muscovite and Li-micas not only traces the processes of W enrichment by magmatic differentiation and volatiles but also traces the leaching of W by the fluids. Therefore, micas are indicators not only for the magmatic–hydrothermal evolution of granite, but also for tungsten mineralization.

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Hedenquist, Jeffrey W., Masahiro Aoki, and Hiroshi Shinohara. "Flux of volatiles and ore-forming metals from the magmatic-hydrothermal system of Satsuma Iwojima volcano." Geology 22, no. 7 (1994): 585. http://dx.doi.org/10.1130/0091-7613(1994)022<0585:fovaof>2.3.co;2.

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Giuliani, Andrea, and D. Graham Pearson. "Kimberlites: From Deep Earth to Diamond Mines." Elements 15, no. 6 (December 1, 2019): 377–80. http://dx.doi.org/10.2138/gselements.15.6.377.

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Kimberlites are rare, enigmatic, low-volume igneous rocks. They are highly enriched in magnesium, volatiles (CO2 and H2O) and incompatible trace elements and are thought to be the most deeply derived (>150 km) magmatic rocks on Earth. Kimberlites occur in ancient and thick continental lithosphere, forming intrusive sheets and composite pipes, commonly in clusters. Despite their rarity, kimberlites have attracted considerable attention because they entrain not only abundant mantle fragments but also diamonds, which can provide a uniquely rich picture of the deep Earth. This issue summarises current thinking on kimberlite petrology, geochemistry, and volcanology and outlines the outstanding questions on the genesis of kimberlites and associated diamond mines.

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Broska, Igor, and Igor Petrík. "Genesis and stability of accessory phosphates in silicic magmatic rocks: a Western Carpathian case study." Mineralogia 39, no. 1-2 (January 1, 2008): 53–66. http://dx.doi.org/10.2478/v10002-008-0004-6.

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Genesis and stability of accessory phosphates in silicic magmatic rocks: a Western Carpathian case studyThe formation of accessory phosphates in granites reflects many chemical and physical factors, including magma composition, oxidation state, concentrations of volatiles and degree of differentiation. The geotectonic setting of granites can be judged from the distribution and character of their phosphates. Robust apatite crystallization is typical of the early magmatic crystallization of I-type granitoids, and of late magmatic stages when increased Ca activity may occur due to the release of anorthite from plagioclase. Although S-type granites also accumulate apatite in the early stages, increasing phosphorus in late differentiates is common due to their high ASI. The apatite from the S-types is enriched in Mn compared to that in I-type granites. A-type granites characteristically contain minor amounts of apatite due to low P concentrations in their magmas. Monazite is typical of S-type granites but it can also become stable in late I-type differentiates. Huttonite contents in monazite correlate roughly positively with temperature. The cheralite molecule seems to be highest in monazite from the most evolved granites enriched in B and F. Magmatic xenotime is common mainly in the S-type granites, but crystallization of secondary xenotime is not uncommon. The formation of the berlinite molecule in feldspars in peraluminous melts may suppress phosphate precipitation and lead to distributional inhomogeneities. Phosphate mobility commonly leads to the formation of phosphate veinlets in and outside granite bodies. The stability of phosphates in the superimposed, metamorphic processes is restricted. Both monazite-(Ce) and xenotime-(Y) are unstable during fluid-activated overprinting. REE accessories, especially monazite and allanite, show complex replacement patterns culminating in late allanite and epidote formation.

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Day, James M. D., and Frederic Moynier. "Evaporative fractionation of volatile stable isotopes and their bearing on the origin of the Moon." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 372, no. 2024 (September 13, 2014): 20130259. http://dx.doi.org/10.1098/rsta.2013.0259.

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The Moon is depleted in volatile elements relative to the Earth and Mars. Low abundances of volatile elements, fractionated stable isotope ratios of S, Cl, K and Zn, high μ ( 238 U/ 204 Pb) and long-term Rb/Sr depletion are distinguishing features of the Moon, relative to the Earth. These geochemical characteristics indicate both inheritance of volatile-depleted materials that formed the Moon and planets and subsequent evaporative loss of volatile elements that occurred during lunar formation and differentiation. Models of volatile loss through localized eruptive degassing are not consistent with the available S, Cl, Zn and K isotopes and abundance data for the Moon. The most probable cause of volatile depletion is global-scale evaporation resulting from a giant impact or a magma ocean phase where inefficient volatile loss during magmatic convection led to the present distribution of volatile elements within mantle and crustal reservoirs. Problems exist for models of planetary volatile depletion following giant impact. Most critically, in this model, the volatile loss requires preferential delivery and retention of late-accreted volatiles to the Earth compared with the Moon. Different proportions of late-accreted mass are computed to explain present-day distributions of volatile and moderately volatile elements (e.g. Pb, Zn; 5 to >10%) relative to highly siderophile elements (approx. 0.5%) for the Earth. Models of early magma ocean phases may be more effective in explaining the volatile loss. Basaltic materials (e.g. eucrites and angrites) from highly differentiated airless asteroids are volatile-depleted, like the Moon, whereas the Earth and Mars have proportionally greater volatile contents. Parent-body size and the existence of early atmospheres are therefore likely to represent fundamental controls on planetary volatile retention or loss.

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Orsoev, D. A. "Anorthosites of the low-sulfide platiniferous horizon (Reef I) in the upper riphean Yoko-Dovyren massif (Northern Cisbaikalia): new data on the composition, PGE-Cu-Ni mineralization, fluid regime and formation conditions." Геология рудных месторождений 61, no. 4 (August 13, 2019): 15–43. http://dx.doi.org/10.31857/s0016-777061415-43.

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The carried out studies based on new data allowed to give mineralogical, petro- and geochemical characteristics to anorthosites, which are the main link and the major concentrator of PGE and Au in the composition of low-sulfide platinum metal mineralization, localized in a specific taxitic horizon (Reef I) of the Yoko-Dovyren massif. The revealed features of the composition and structure of this horizon indicate that the formation of anorthosites is caused by both the actual magmatic and the late- and postmagmatic processes with a high activity of volatile components. The horizon occurrence can be explained in terms of the “compaction” hypothesis and thermal shrinkage phenomenon. At the boundary of the rocks contrasting in composition and characteristics, when they are cooled, weakened zones form up to cracks and cavities, into which the interstitial leucocratic melt and volatiles squeezed out of the underlying horizons of the massif sucked as a result of the decompression effect. The revealed patterns of changes in the compositions of Pl (82-88% An), Ol (78-81% Fo), Cpx (40-44% En, 9-18% Fs, 41-47% Wo) and Opx (74-78% En, 16-24% Fs, 2-5% Wo) indicate fractional crystallization of the detrital melt. The processes of fluid-magmatic interaction led to a considerable heterogeneity of anorthosites and other rocks, the formation of disequilibrium mineral associations and concentration of ore-generating components. Sulfide associations are considered as products of the subsolidus transformation of solid solutions (mss and iss + poss) formed during the crystallization of an immiscible sulfide liquid enriched in Cu. It is demonstrated that noble metals were associated not only with a limited amount of sulfide liquid. The major part of noble metals with “crust” components (Sn, Pb, Hg, Bi, As, Sb, Te, S, etc.) entered the anorthosite cavities along with volatile components and chlorine, thus causing an abundance of native minerals among platinoids. The decisive role of reduced gases (H2, CH4, CO), H2O and Cl in the genesis of precious metal minerals is estimated.

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Gao, Jinliang, Jiaqi Liu, David R. Hilton, Fanchao Meng, Zhongping Li, Lina Zhai, Chunqing Sun, and Lei Zhang. "The chemical and isotopic compositions of volatiles in magmatic hydrothermal fluids beneath the Songliao Basin, northeastern China." Chemical Geology 465 (August 2017): 11–20. http://dx.doi.org/10.1016/j.chemgeo.2017.05.015.

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Shevenell, Lisa, and Fraser Goff. "Addition of magmatic volatiles into the hot spring waters of loowit canyon, Mount St. Helens, Washington, USA." Bulletin of Volcanology 55, no. 7 (September 1993): 489–503. http://dx.doi.org/10.1007/bf00304592.

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Zajacz, Zoltán. "The effect of melt composition on the partitioning of oxidized sulfur between silicate melts and magmatic volatiles." Geochimica et Cosmochimica Acta 158 (June 2015): 223–44. http://dx.doi.org/10.1016/j.gca.2015.01.036.

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Iacovino, Kayla, Kim Ju-Song, Thomas Sisson, Jacob Lowenstern, Ri Kuk-Hun, Jang Jong-Nam, Song Kun-Ho, et al. "Quantifying gas emissions from the “Millennium Eruption” of Paektu volcano, Democratic People’s Republic of Korea/China." Science Advances 2, no. 11 (November 2016): e1600913. http://dx.doi.org/10.1126/sciadv.1600913.

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Paektu volcano (Changbaishan) is a rhyolitic caldera that straddles the border between the Democratic People’s Republic of Korea and China. Its most recent large eruption was the Millennium Eruption (ME; 23 km3dense rock equivalent) circa 946 CE, which resulted in the release of copious magmatic volatiles (H2O, CO2, sulfur, and halogens). Accurate quantification of volatile yield and composition is critical in assessing volcanogenic climate impacts but is challenging, particularly for events before the satellite era. We use a geochemical technique to quantify volatile composition and upper bounds to yields for the ME by examining trends in incompatible trace and volatile element concentrations in crystal-hosted melt inclusions. We estimate that the ME could have emitted as much as 45 Tg of S to the atmosphere. This is greater than the quantity of S released by the 1815 eruption of Tambora, which contributed to the “year without a summer.” Our maximum gas yield estimates place the ME among the strongest emitters of climate-forcing gases in the Common Era. However, ice cores from Greenland record only a relatively weak sulfate signal attributed to the ME. We suggest that other factors came into play in minimizing the glaciochemical signature. This paradoxical case in which high S emissions do not result in a strong glacial sulfate signal may present a way forward in building more generalized models for interpreting which volcanic eruptions have produced large climate impacts.

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Liu, Huimin, Zhaojun Song, Hongbo Yan, Wenyu Wang, Xinru Wang, Yifang Sun, and Haonan Li. "New View on the Genesis of the Bashuihe Pluton, Laoshan Granites, China: Indications from Fluid Inclusions and H–O Isotopes." Geofluids 2021 (February 6, 2021): 1–12. http://dx.doi.org/10.1155/2021/6655431.

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Oval caves have recently been discovered in the Bashuihe granite pluton of Laoshan Mountain, China. Oval caves typically occur in alkaline granites. This study conducted microthermometry and stable isotope analysis of quartz inclusions from oval caves and host rocks from the Bashuihe pluton to reconstruct the diagenetic evolutionary history of the Laoshan area. The temperature measurement results indicated a homogenisation temperature range from 162.5 to 261.6°C (mean 203.9°C), a salinity range of 2.1–8.3 wt% (mean 5.07 wt%), and a density range of 0.8–0.98 g/cm3 (mean 0.90 g/cm3), indicating a low-temperature, low-salinity, and low-density fluid. The emplacement depth ranged from 2.73 km to 4.43 km, indicating medium-shallow granite. A hydrogen and oxygen isotope analysis ( δ D = − 83.58 – − 67.17 , δ 18 O H 2 O = 0.83 – 0.39 ) revealed that the diagenetic fluids of the Bashuihe pluton represented a mixed hydrothermal solution composed of meteoric water and magmatic water. The results of a whole rock, H–O isotopes, rare earth element, and high field strength element analysis on the Laoshan alkali granites suggest significant hydrothermal activity in the late stage of magmatism. Primary oval caves in the Bashuihe pluton most likely evolved in the following sequence: fluid was enriched in the late diagenetic stage, diagenetic minerals crystallised under low temperature and pressure conditions, the crystallisation rate accelerated, and the magma condensed rapidly. Moreover, the increase in magma fluid enabled the movement and convergence of fluid. The accumulated fluid and volatiles occupied more space, and rapid magma condensation trapped the accumulated fluid and volatiles in the pluton, forming the oval granite cave. This research provides a crucial theoretical reference for the development and utilisation of underground space and engineering buildings in granite regions.

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Newman, Gregory A., Philip E. Wannamaker, and Gerald W. Hohmann. "On the detectability of crustal magma chambers using the magnetotelluric method." GEOPHYSICS 50, no. 7 (July 1985): 1136–43. http://dx.doi.org/10.1190/1.1441987.

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We utilized resistivity models of silicic magma chambers to explore effects that layering can have on three‐dimensional (3-D) magnetotelluric (MT) responses. Model simulations show that MT detection of magma may depend strongly on its one‐dimensional host. The 3-D responses of a model juvenile magma body which is connected electrically to deeper, less resistive crust of regional extent are very subdued. However, intermediate and mature magmatic systems, leaving magma no longer in contact with lower, less resistive crust, may be detectable with the MT method. Further, the release and ascent of volatiles from crystallizing melt may lead to fracturing above the chamber, thereby establishing electrical contact of the magma with shallow, conductive crust and amplifying its MT response.

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Papavasiliou, K., P. Voudouris, C. Kanellopoulos, D. Alfieris, and S. Xydous. "MINERALOGY AND GEOCHEMISTRY OF THE TRIADESGALANA PB-ZN-AG-AU INTERMEDIATE-HIGH SULFIDATION EPITHERMAL MINERALIZATION, MILOS ISLAND, GREECE." Bulletin of the Geological Society of Greece 50, no. 4 (July 28, 2017): 1969. http://dx.doi.org/10.12681/bgsg.11943.

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The Triades-Galana Pb-Zn-Ag-Au mineralization is a shallow-submarine epithermal mineralization located along NE-trending faults, NW Milos Island, Greece. It is hosted in 2.5–1.4 Ma pyroclastic rocks and is genetically related to andesitic/dacitic lava domes. Mineralization occurs as breccias, quartz-barite galena veins and stockworks within sericite-adularia or kaolinitic altered rocks. The mineralization is enriched in Mo, W and base- and precious metals (e.g. Pb, Zn, Ag) similarly to the neighbouring mineralization at Kondaros-Katsimouti and Vani, indicating common source of metals from a deep buried granitoid feeding western Milos with metals and volatiles. Paragenetic relations suggest early deposition of pyrite, followed by famatinite, polybasite and Ag-rich tetrahedrite, and then by enargite, suggesting fluctuating sulfidation states during ore formation. The evolution from Sb- towards As-rich enrichment indicate a renewed magmatic pulse (probably in the form of magmatic gases) in the hydrothermal system. Silver is present in the structure of sulfosalts (up to 66.2 wt.% in polybasite-pearceite, 15.1 wt.% in tetrahedrite and 60 wt. % in pyrargyrite). Boiling processes (as evidenced by the presence of adularia accompanying intermediate-sulfidation ore) and mixing with seawater (presence of hypogene lead chlorides) and contemporaneous uplift, contributed to ore formation.

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Palinkaš, Sabina, Zlatko Peltekovski, Goran Tasev, Todor Serafimovski, Danijela Šmajgl, Kristijan Rajič, Jorge Spangenberg, Kai Neufeld, and Ladislav Palinkaš. "The Role of Magmatic and Hydrothermal Fluids in the Formation of the Sasa Pb-Zn-Ag Skarn Deposit, Republic of Macedonia." Geosciences 8, no. 12 (November 29, 2018): 444. http://dx.doi.org/10.3390/geosciences8120444.

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The Sasa Pb-Zn-Ag deposit belongs to the group of distal base metal skarn deposits. The deposit is located within the Serbo-Macedonian massif, a metamorphosed crystalline terrain of Precambrian to Paleozoic age. The mineralization, hosted by Paleozoic marbles, shows a strong lithological control. It is spatially and temporally associated with the calc-alkaline to shoshonitic post-collisional magmatism that affected the Balkan Peninsula during the Oligocene–Miocene time period and resulted in the formation of numerous magmatic–hydrothermal ore deposits. The mineralization at the Sasa Pb-Zn-Ag deposit shows many distinctive features typical for base metal skarn deposits including: (1) a carbonate lithology as the main immediate host of the mineralization; (2) a close spatial relation between the mineralization and magmatic bodies of an intermediate composition; (3) a presence of the prograde anhydrous Ca-Fe-Mg-Mn-silicate and the retrograde hydrous Ca-Fe-Mg-Mn ± Al-silicate mineral assemblages; (4) a deposition of base metal sulfides, predominately galena and sphalerite, during the hydrothermal stage; and (5) a post-ore stage characterized by the deposition of a large quantity of carbonates. The relatively simple, pyroxene-dominated, prograde mineralization at the Sasa Pb-Zn-Ag skarn deposit represents a product of the infiltration-driven metasomatism which resulted from an interaction of magmatic fluids with the host marble. The prograde stage occurred under conditions of a low water activity, low oxygen, sulfur and CO2 fugacities and a high K+/H+ molar ratio. The minimum pressure–temperature (P–T) conditions were estimated at 30 MPa and 405 °C. Mineralizing fluids were moderately saline and low density Ca-Na-chloride bearing aqueous solutions. The transition from the prograde to the retrograde stage was triggered by cooling of the system below 400 °C and the resulting ductile-to-brittle transition. The brittle conditions promoted reactivation of old (pre-Tertiary) faults and allowed progressive infiltration of ground waters and therefore increased the water activity and oxygen fugacity. At the same time, the lithostatic to hydrostatic transition decreased the pressure and enabled a more efficient degassing of magmatic volatiles. The progressive contribution of magmatic CO2 has been recognized from the retrograde mineral paragenesis as well as from the isotopic composition of associated carbonates. The retrograde mineral assemblages, represented by amphiboles, epidote, chlorites, magnetite, pyrrhotite, quartz and carbonates, reflect conditions of high water activity, high oxygen and CO2 fugacities, a gradual increase in the sulfur fugacity and a low K+/H+ molar ratio. Infiltration fluids carried MgCl2 and had a slightly higher salinity compared to the prograde fluids. The maximum formation conditions for the retrograde stage are set at 375 °C and 200 MPa. The deposition of ore minerals, predominantly galena and sphalerite, occurred during the hydrothermal phase under a diminishing influence of magmatic CO2. The mixing of ore-bearing, Mg-Na-chloride or Fe2+-chloride, aqueous solutions with cold and diluted ground waters is the most plausible reason for the destabilization of metal–chloride complexes. However, neutralization of relatively acidic ore-bearing fluids during the interaction with the host lithology could have significantly contributed to the deposition. The post-ore, carbonate-dominated mineralization was deposited from diluted Ca-Na-Cl-bearing fluids of a near-neutral pH composition. The corresponding depositional temperature is estimated at below 300 °C.

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Kerrich, R., and B. J. Fryer. "Lithophile-element systematics of Archean greenstone belt Au–Ag vein deposits: implications for source processes." Canadian Journal of Earth Sciences 25, no. 6 (June 1, 1988): 945–53. http://dx.doi.org/10.1139/e88-095.

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Potassic alteration domains of greenstone belt lode gold deposits are characterized by systematic partitioning between lithophile elements. K, Rb, and Ba are generally co-enriched and linearly correlated over almost three orders of magnitude in abundance, where K/Rb = 220–400 and K/Ba = 30–85; K/Cs (~104) and K/Tl (~2 × 104) are also correlated, though more weakly. Lithium abundances and Rb/Sr ratios are erratic in altered rocks. These interelement trends, collectively, are present in deposits variously hosted by ultramafic, mafic, or felsic volcanic rocks and sediments or granitoids. Magmatic processes involving crystal fractionation of biotite, K-feldspar, and plagioclase generate trends to systematically diminished K/Rb (≥50), K/Li, K/Cs, and K/Tl but enhanced K/Ba (≤8 × 103) and Rb/Sr in most late-stage differentiates. Such "late-stage" trends are the rule in "magmatophile" deposits, including the Archean Cadillac molybdenite deposit, Phanerozoic Cu- and Mo-"porphyry" deposits, Sn–W greisens, and most pegmatites. Accordingly, magmatic processes of this type can be ruled out as the dominant source of volatiles for gold-forming systems. The compliance of K/Rb and K/Ba ratios in potassic alteration domains of Au deposits with values characteristic of main-trend igneous rocks, or "average" crust, implies that K, Rb, and Ba were partitioned into the hydrothermal ore-forming fluids in approximately the same ratios as in the source rocks. Dehydration reactions in the source rocks or equilibration of fluids with source rocks under conditions of low water/rock ratio, rather than magmatic processes, may satisfy the requirement for proportional K, Rb, and Ba co-enrichment.

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Chambefort, Isabelle, John H. Dilles, and Anthony A. Longo. "Amphibole Geochemistry of the Yanacocha Volcanics, Peru: Evidence for Diverse Sources of Magmatic Volatiles Related to Gold Ores." Journal of Petrology 54, no. 5 (March 1, 2013): 1017–46. http://dx.doi.org/10.1093/petrology/egt004.

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McCubbin, Francis M., Bradley L. Jolliff, Hanna Nekvasil, Paul K. Carpenter, Ryan A. Zeigler, Andrew Steele, Stephen M. Elardo, and Donald H. Lindsley. "Fluorine and chlorine abundances in lunar apatite: Implications for heterogeneous distributions of magmatic volatiles in the lunar interior." Geochimica et Cosmochimica Acta 75, no. 17 (September 2011): 5073–93. http://dx.doi.org/10.1016/j.gca.2011.06.017.

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39

Imura, Takumi, Yusuke Minami, Tsukasa Ohba, Akiko Matsumoto, Antonio Arribas, and Mitsuhiro Nakagawa. "Hydrothermal Aluminum-Phosphate-Sulfates in Ash from the 2014 Hydrothermal Eruption at Ontake Volcano, Central Honshu, Japan." Minerals 9, no. 8 (July 29, 2019): 462. http://dx.doi.org/10.3390/min9080462.

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Aluminum-phosphate-sulfates (APS) of the alunite supergroup occur in igneous rocks within zones of advanced argillic and silicic alteration in porphyry and epithermal ore environments. In this study we report on the presence of woodhouseite-rich APS in ash from the 27 September 2014 hydrothermal eruption of Ontake volcano. Scanning electron microscope coupled with energy dispersive X-ray spectrometer (SEM-EDS) and field emission (FE)-SEM-EDS observations show two types of occurrence of woodhouseite: (a) as cores within chemically zoned alunite-APS crystals (Zoned-alunite-woodhouseite-APS), and (b) as a coherent single-phase mineral in micro-veinlets intergrown with similar micro-veinlets of silica minerals (Micro-wormy-vein woodhouseite-APS). The genetic environment of APS minerals at Ontake volcano is that of a highly acidic hydrothermal system existing beneath the volcano summit, formed by condensation in magmatic steam and/or ground waters of sulfur-rich magmatic volatiles exsolved from the magma chamber beneath Mt. Ontake. Under these conditions, an advanced argillic alteration assemblage forms, which is composed of silica, pyrophyllite, alunite and kaolinite/dickite, plus APS, among other minerals. The discovery of woodhouseite in the volcanic ash of the Ontake 2014 hydrothermal eruption represents the first reported presence of APS within an active volcano. Other volcanoes in Japan and elsewhere with similar phreatic eruptions ejecting altered ash fragments will likely contain APS minerals derived from magmatic-hydrothermal systems within the subvolcanic environment. The presence of APS minerals within the advanced argillic zone below the summit vent of Ontake volcano, together with the prior documentation of phyllic and potassically altered ash fragments, provides evidence for the existence within an active volcano in Japan of an alteration column comparable to that of porphyry copper systems globally.

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Forni, Francesca, Wim Degruyter, Olivier Bachmann, Gianfilippo De Astis, and Silvio Mollo. "Long-term magmatic evolution reveals the beginning of a new caldera cycle at Campi Flegrei." Science Advances 4, no. 11 (November 2018): eaat9401. http://dx.doi.org/10.1126/sciadv.aat9401.

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Understanding the mechanisms that control the accumulation of large silicic magma bodies in the upper crust is key to determining the potential of volcanoes to form caldera-forming eruptions. Located in one of the most populated regions on Earth, Camp Flegrei is an active and restless volcano that has produced two cataclysmic caldera-forming eruptions and numerous smaller eruptive events over the past 60,000 years. Here, we combine the results of an extensive petrological survey with a thermomechanical model to investigate how the magmatic system shifts from frequent, small eruptions to large caldera-forming events. Our data reveal that the most recent eruption of Monte Nuovo is characterized by highly differentiated magmas akin to those that fed the pre-caldera activity and the initial phases of the caldera-forming eruptions. We suggest that this eruption is an expression of a state shift in magma storage conditions, whereby substantial amounts of volatiles start to exsolve in the shallow reservoir. The presence of an exsolved gas phase has fundamental consequences for the physical properties of the reservoir and may indicate that a large magma body is currently accumulating underneath Campi Flegrei.

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Gaeta, M., G. Fabrizio, and G. Cavarretta. "F-phlogopites in the Alban Hills Volcanic District (Central Italy): indications regarding the role of volatiles in magmatic crystallisation." Journal of Volcanology and Geothermal Research 99, no. 1-4 (June 2000): 179–93. http://dx.doi.org/10.1016/s0377-0273(00)00172-4.

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JESUS, J. V. M., A. C. SANTOS, J. C. MENDES, W. H. SANTOS, C. A. Q. REGO, and M. C. GERALDES. "Davis Bank Petrogenesis, Vitória-Trindade Chain, South Atlantic: Volatiles Role (H2O and CO2) in the Davis Bank Magmatic Evolution." Anuário do Instituto de Geociências - UFRJ 42, no. 3 (September 30, 2019): 237–53. http://dx.doi.org/10.11137/2019_3_237_253.

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Zajacz, Zoltán, Philip A. Candela, Philip M. Piccoli, and Carmen Sanchez-Valle. "The partitioning of sulfur and chlorine between andesite melts and magmatic volatiles and the exchange coefficients of major cations." Geochimica et Cosmochimica Acta 89 (July 2012): 81–101. http://dx.doi.org/10.1016/j.gca.2012.04.039.

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Coulson, Ian, Gregory Dipple, and Mati Raudsepp. "Evolution of HF and HCl activity in magmatic volatiles of the gold-mineralized Emerald Lake pluton, Yukon Territory, Canada." Mineralium Deposita 36, no. 6 (September 1, 2001): 594–606. http://dx.doi.org/10.1007/s001260100191.

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Smirnov, S. Z., I. A. Maksimovich, A. A. Kotov, T. Yu Timina, T. A. Bulbak, A. A. Tomilenko, D. V. Kuzmin, A. Ya Shevko, and A. V. Rybin. "Behavior of volatiles in the magmatic reservoirs of large-scale eruptions of Pleistocene-Holocene calderas of Iturup Island (Kuril Islands)." Geosystems of Transition Zones 2, no. 4 (2018): 365–76. http://dx.doi.org/10.30730/2541-8912.2018.2.4.365-376.

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Notsu, Kenji, Rumi Sohrin, Hideki Wada, Tatsuya Tsuboi, Hirochika Sumino, Toshiya Mori, Urumu Tsunogai, et al. "Leakage of magmatic–hydrothermal volatiles from a crater bottom formed by a submarine eruption in 1989 at Teishi Knoll, Japan." Journal of Volcanology and Geothermal Research 270 (January 2014): 90–98. http://dx.doi.org/10.1016/j.jvolgeores.2013.11.017.

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McCubbin, Francis M., Kathleen E. Vander Kaaden, Romain Tartèse, Rachel L. Klima, Yang Liu, James Mortimer, Jessica J. Barnes, et al. "Magmatic volatiles (H, C, N, F, S, Cl) in the lunar mantle, crust, and regolith: Abundances, distributions, processes, and reservoirs." American Mineralogist 100, no. 8-9 (August 2015): 1668–707. http://dx.doi.org/10.2138/am-2015-4934ccbyncnd.

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Ohwada, Michiko, Kohei Kazahaya, Jun'ich Itoh, Noritoshi Morikawa, Masaaki Takahashi, Hiroshi A. Takahashi, Akihiko Inamura, Masaya Yasuhara, and Hitoshi Tsukamoto. "Passive degassing of magmatic volatiles from Iwate volcano, NE Japan, based on three-dimensional measurement of helium isotopes in groundwater." Journal of Geophysical Research: Solid Earth 117, B2 (February 2012): n/a. http://dx.doi.org/10.1029/2011jb008532.

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Fogel, Robert A., and Malcolm J. Rutherford. "Magmatic volatiles in primitive lunar glasses: I. FTIR and EPMA analyses of Apollo 15 green and yellow glasses and revision of the volatile-assisted fire-fountain theory." Geochimica et Cosmochimica Acta 59, no. 1 (January 1995): 201–15. http://dx.doi.org/10.1016/0016-7037(94)00377-x.

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Inguaggiato, Salvatore, Fabio Vita, Marianna Cangemi, Claudio Inguaggiato, and Lorenzo Calderone. "The Monitoring of CO2 Soil Degassing as Indicator of Increasing Volcanic Activity: The Paroxysmal Activity at Stromboli Volcano in 2019–2021." Geosciences 11, no. 4 (April 8, 2021): 169. http://dx.doi.org/10.3390/geosciences11040169.

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Since 2016, Stromboli volcano has shown an increase of both frequency and energy of the volcanic activity; two strong paroxysms occurred on 3 July and 28 August 2019. The paroxysms were followed by a series of major explosions, which culminated on January 2021 with magma overflows and lava flows along the Sciara del Fuoco. This activity was monitored by the soil CO2 flux network of Istituto Nazionale di Geofisica e Vulcanologia (INGV), which highlighted significant changes before the paroxysmal activity. The CO2 flux started to increase in 2006, following a long-lasting positive trend, interrupted by short-lived high amplitude transients in 2016–2018 and 2018–2019. This increasing trend was recorded both in the summit and peripheral degassing areas of Stromboli, indicating that the magmatic gas release affected the whole volcanic edifice. These results suggest that Stromboli volcano is in a new critical phase, characterized by a great amount of volatiles exsolved by the shallow plumbing system, which could generate other energetic paroxysms in the future.

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Journal articles on the topic 'Magmatic Volatiles'

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