Subjects -> MINES AND MINING INDUSTRY (Total: 81 journals)
Showing 1 - 42 of 42 Journals sorted alphabetically
American Mineralogist     Hybrid Journal   (Followers: 16)
Applied Earth Science : Transactions of the Institutions of Mining and Metallurgy     Hybrid Journal   (Followers: 4)
Archives of Mining Sciences     Open Access   (Followers: 3)
AusiMM Bulletin     Full-text available via subscription   (Followers: 1)
BHM Berg- und Hüttenmännische Monatshefte     Hybrid Journal   (Followers: 2)
Canadian Mineralogist     Full-text available via subscription   (Followers: 7)
Clay Minerals     Hybrid Journal   (Followers: 9)
Clays and Clay Minerals     Hybrid Journal   (Followers: 5)
Coal Science and Technology     Full-text available via subscription   (Followers: 3)
Contributions to Mineralogy and Petrology     Hybrid Journal   (Followers: 14)
Environmental Geochemistry and Health     Hybrid Journal   (Followers: 2)
European Journal of Mineralogy     Hybrid Journal   (Followers: 14)
Exploration and Mining Geology     Full-text available via subscription   (Followers: 3)
Extractive Industries and Society     Hybrid Journal   (Followers: 2)
Gems & Gemology     Full-text available via subscription   (Followers: 2)
Geology of Ore Deposits     Hybrid Journal   (Followers: 5)
Geomaterials     Open Access   (Followers: 3)
Geotechnical and Geological Engineering     Hybrid Journal   (Followers: 9)
Ghana Mining Journal     Full-text available via subscription   (Followers: 3)
Gold Bulletin     Hybrid Journal   (Followers: 2)
Inside Mining     Full-text available via subscription  
International Journal of Coal Geology     Hybrid Journal   (Followers: 4)
International Journal of Coal Preparation and Utilization     Hybrid Journal   (Followers: 2)
International Journal of Coal Science & Technology     Open Access   (Followers: 1)
International Journal of Hospitality & Tourism Administration     Hybrid Journal   (Followers: 15)
International Journal of Mineral Processing     Hybrid Journal   (Followers: 8)
International Journal of Minerals, Metallurgy, and Materials     Hybrid Journal   (Followers: 11)
International Journal of Mining and Geo-Engineering     Open Access   (Followers: 4)
International Journal of Mining and Mineral Engineering     Hybrid Journal   (Followers: 8)
International Journal of Mining Engineering and Mineral Processing     Open Access   (Followers: 6)
International Journal of Mining Science and Technology     Open Access   (Followers: 4)
International Journal of Mining, Reclamation and Environment     Hybrid Journal   (Followers: 6)
International Journal of Rock Mechanics and Mining Sciences     Hybrid Journal   (Followers: 9)
Journal of Analytical and Numerical Methods in Mining Engineering     Open Access  
Journal of Applied Geophysics     Hybrid Journal   (Followers: 17)
Journal of Central South University     Hybrid Journal   (Followers: 1)
Journal of China Coal Society     Open Access  
Journal of China University of Mining and Technology     Full-text available via subscription   (Followers: 1)
Journal of Convention & Event Tourism     Hybrid Journal   (Followers: 6)
Journal of Geology and Mining Research     Open Access   (Followers: 10)
Journal of Human Resources in Hospitality & Tourism     Hybrid Journal   (Followers: 9)
Journal of Materials Research and Technology     Open Access   (Followers: 2)
Journal of Metamorphic Geology     Hybrid Journal   (Followers: 17)
Journal of Mining Institute     Open Access  
Journal of Mining Science     Hybrid Journal   (Followers: 5)
Journal of Quality Assurance in Hospitality & Tourism     Hybrid Journal   (Followers: 6)
Journal of Sustainable Mining     Open Access   (Followers: 3)
Journal of the Southern African Institute of Mining and Metallurgy     Open Access   (Followers: 6)
Lithology and Mineral Resources     Hybrid Journal   (Followers: 4)
Lithos     Hybrid Journal   (Followers: 12)
Mine Water and the Environment     Hybrid Journal   (Followers: 5)
Mineral Economics     Hybrid Journal   (Followers: 2)
Mineral Processing and Extractive Metallurgy : Transactions of the Institutions of Mining and Metallurgy     Hybrid Journal   (Followers: 14)
Mineral Processing and Extractive Metallurgy Review     Hybrid Journal   (Followers: 5)
Mineralium Deposita     Hybrid Journal   (Followers: 5)
Mineralogia     Open Access   (Followers: 2)
Mineralogical Magazine     Hybrid Journal   (Followers: 1)
Mineralogy and Petrology     Hybrid Journal   (Followers: 5)
Minerals     Open Access   (Followers: 2)
Minerals & Energy - Raw Materials Report     Hybrid Journal   (Followers: 1)
Minerals Engineering     Hybrid Journal   (Followers: 14)
Mining Engineering     Full-text available via subscription   (Followers: 7)
Mining Journal     Full-text available via subscription   (Followers: 4)
Mining Report     Hybrid Journal   (Followers: 3)
Mining Technology : Transactions of the Institutions of Mining and Metallurgy     Hybrid Journal   (Followers: 4)
Mining, Metallurgy & Exploration     Hybrid Journal  
Natural Resources & Engineering     Hybrid Journal  
Natural Resources Research     Hybrid Journal   (Followers: 4)
Neues Jahrbuch für Mineralogie - Abhandlungen     Full-text available via subscription   (Followers: 1)
Physics and Chemistry of Minerals     Hybrid Journal   (Followers: 4)
Podzemni Radovi     Open Access  
Rangeland Journal     Hybrid Journal   (Followers: 4)
Réalités industrielles     Full-text available via subscription  
Rem : Revista Escola de Minas     Open Access  
Resources Policy     Hybrid Journal   (Followers: 4)
Reviews in Mineralogy and Geochemistry     Hybrid Journal   (Followers: 5)
Revista del Instituto de Investigación de la Facultad de Ingeniería Geológica, Minera, Metalurgica y Geográfica     Open Access  
Rock Mechanics and Rock Engineering     Hybrid Journal   (Followers: 9)
Rocks & Minerals     Hybrid Journal   (Followers: 5)
Rudarsko-geološko-naftni Zbornik     Open Access  
Transactions of Nonferrous Metals Society of China     Hybrid Journal   (Followers: 9)
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Journal Cover
Mineralogy and Petrology
Journal Prestige (SJR): 0.833
Citation Impact (citeScore): 2
Number of Followers: 5  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1438-1168 - ISSN (Online) 0930-0708
Published by Springer-Verlag Homepage  [2626 journals]
  • Clinopyroxene megacrysts from Marion Island, Antarctic Ocean: evidence for
           a late stage shallow origin
    • Abstract: Abstract Clinopyroxene megacrysts (up to 5 cm) from a scoria cone on Marion Island, Antarctic Ocean are zoned, with compositionally distinct low (Al + Ti) and high (Al + Ti) patches arranged haphazardly throughout crystals. Inclusions of olivine, pyrrhotite, oxides, sulphides, and rounded inclusions with euhedral micro-crystals interpreted as former melt inclusions are observed. Olivine inclusions have variable compositions, ranging from primary Ti-poor crystals to Ti-rich crystals hosting secondary haematite crystals formed by hydrogenation. The crystals contain voids that are concentrated in the middle of each crystal indicating that the initial crystal growth was skeletal. Subsequent crystallisation filled in the skeletal framework creating the patchy zoning in the crystals. The Marion Island megacrysts are not homogenous, but the combination of crustal clinopyroxene compositions, primary and hydrogenated olivine, and the mode of eruption in scoria eruptions indicates that these crystals most likely formed in a shallow magma chamber. Primary olivines crystallised from a mafic magma and secondary altered olivines were incorporated into a rapidly growing megacryst in a super-saturated, fluid-rich environment, prior to being ejected onto surface in a scoria eruption.
      PubDate: 2019-04-01
      DOI: 10.1007/s00710-018-00651-x
       
  • Early Precambrian tectono-thermal events in Southern Jilin Province,
           China: implications for the evolution of Neoarchean to Paleoproterozoic
           crust in the northeastern North China Craton
    • Abstract: Abstract The early Precambrian basement of the North China Craton, China, records a complex history during the Neoarchean and Paleoproterozoic. Southern Jilin Province is one of the best regions to evaluate the early Precambrian crustal growth of the Eastern Block of the North China Craton. We herein present new zircon cathodoluminescence images, U–Pb dates, trace element and Lu–Hf isotope data for three late Neoarchean tonalitic–trondhjemitic–granodioritic (TTG) gneisses and one Paleoproterozoic mafic dyke from Tonghua region, southern Jilin Province. These results lent convincing support to the occurrence of multiple tectono-thermal events in southern Jilin Province during the Archean and Paleoproterozoic, and shed light on the formation and evolution of continental crust in the northeastern Eastern Block. Zircon LA–ICP–MS U–Pb isotopic analyses indicated three episodes of magmatism. Inherited (or captured) zircons with ages of ca. 2.6 Ga provided strong evidence for a pre-2.5 Ga magmatic event in this region. The second magmatic episode occurred at 2556–2522 Ma, as evidenced by extensive exposures of TTG gneisses. The third episode occurred at ca. 2200 Ma and is recorded by several mafic dykes that intruded the Archean TTG gneisses. Metamorphic zircons yielded consistent ages of 2493–2465 Ma, indicating a regional metamorphic event immediately after the late Neoarchean magmatism in southern Jilin Province. Zircon Hf isotope data of the TTG gneisses indicated that the main phase of crustal growth occurred in the late Neoarchean, with a minor input of Mesoarchean continental crustal materials. The combined geochronological, geochemical, and geological data suggested that the three episodes of crustal growth in the northeastern Eastern Block occurred at 2.8–2.7, 2.6–2.5, and 2.2 Ga.
      PubDate: 2019-04-01
      DOI: 10.1007/s00710-018-0649-9
       
  • Mineral chemistry and formation conditions of argentopentlandite-bearing
           albite veins in a metagabbro of the Sedova Zaimka intrusion, Russia
    • Abstract: Abstract This study presents a new occurrence of hydrothermal argentopentlandite, associated with pyrrhotite, chalcopyrite, sphalerite, and galena in albite (± calcite, muscovite, pyrochlore-group minerals, high-Th phases) veins cutting metagabbro of the Sedova Zaimka intrusion, Western Siberia, Russia. The data obtained from petrography, mineral chemistry and fluid inclusion study of the vein-forming minerals do confirm the proposed hydrothermal origin of sulfides and associated gangue minerals from the internally-derived metamorphic fluids generated during potential post-peak contact metamorphic cooling. These ore-forming fluids were Na-dominant and enriched in Si, Al, Fe, Cu, with minor Ca, K, Ta, Nb, U, Th, Zn, Pb, Ni, Ag, Co, Bi, Te, Se, and Cd. They were characterized by moderate temperatures (270–325 °C) and moderate salinities (4.70–7.25 wt% NaCl equiv.) and belong to the NaCl-H2O fluid system with dominant CH4 gas-phase species. It is concluded that the components (metals and other elements) for the vein infill have been transferred from metagabbro by the metamorphic fluid, possibly in a dissolution–transport–precipitation process.
      PubDate: 2019-04-01
      DOI: 10.1007/s00710-018-0648-x
       
  • Flotation and adsorption of quartz with the new collector
           butane-3-heptyloxy-1,2-diamine
    • Abstract: Abstract A new surfactant butane-3-heptyloxy-1,2-diamine [CH3(CH2)6OCH(CH3)CH(NH2)CH2NH2; BHLD] was synthesized. It has been innovatively used as a collector in the flotation of quartz. In this present study, the flotation behaviors of quartz with BHLD were investigated by micro-flotation of quartz. It was found that the recovery of the quartz reaches 98.9%. Furthermore, the hydrogen bond lengths were measured, calculated and simulated in a molecular dynamics (MD) model, and the interaction energy between the four species of BHLD and the quartz surface were determined under vacuum and aqueous conditions. Based on the results of the zeta potential measurements, the FT-IR measurements and the MD simulation in this paper, it is revealed that the BHLD collector adsorbs onto the quartz surface through electrostatic adsorption and hydrogen bond adsorption. Furthermore, micro-flotations were studied by the radial distribution function (RDF) and the relative concentrations. The results show that the hydrogen bond adsorption between the O atom on the quartz surface and the H atom in BHLD are the main interactive forces causing BHLD to adsorb onto the quartz surface. The BHLD cations adsorb significantly more strongly than the BHLD molecules, which agrees well with the results of the micro-flotation tests.
      PubDate: 2019-04-01
      DOI: 10.1007/s00710-018-0639-y
       
  • Structural investigations on bredigite from the Hatrurim Complex
    • Abstract: Abstract Bredigite, Сa7Mg(SiO4)4, is an indicator mineral of metasomatic rocks of the sanidinite facies formed at high temperatures (>800 °C) and low pressures (<1–2 kbar). Bredigite samples from ternesite-gazeevite-larnite pyrometamorphic rocks of the Hatrurim Complex (Negev Desert, Israel) have been studied by electron probe micro analysis and single-crystal diffraction using synchrotron radiation. They are characterized by a relatively uniform composition. The empirical formula calculated on the basis of 16 O atoms per formula unit is: (Ca7.006Na0.015Ba0.014)Σ7.035Mg0.938(Si4.000P0.014)Σ4.014O16. Basic crystallographic data of a sample studied by X-ray diffraction are as follows: orthorhombic symmetry, space group Pnnm, a = 18.38102(17) Å, b = 6.74936(7) Å, c = 10.90328(11) Å, V = 1352.66(2) Å3, Z = 4. Structure solution and subsequent least-squares refinements resulted in a residual of R( F ) = 0.023 for 2584 independent observed reflections with I > 2σ(I) and 149 parameters. To the best of our knowledge this is the first detailed structural investigation on natural bredigite. In contrast to previous studies on samples retrieved from metallurgical slags there was no need to describe the structure in the acentric space group Pnn2. Furthermore, the problem of Ba incorporation into the bredigite structure is discussed. Data on the composition of Ba-bearing bredigites from pyrometamorphic rocks of the Hatrurim Complex from Jordan with simplified formula Ba0.7Ca13.3Mg2(SiO4)8 (based on 32 oxygen atoms) are provided for the first time, pointing out perspectives of finding new Ba-bearing minerals isostructural with bredigite in nature.
      PubDate: 2019-04-01
      DOI: 10.1007/s00710-018-0646-z
       
  • Rare aluminium phosphates and sulphates (APS) and clay mineral assemblages
           in silicified hydraulic breccia hosted by a Permian granite (Velence Mts.,
           Hungary) as indicators of a high sulfidation type epithermal system
    • Abstract: Abstract Uncommon micrometer-sized aluminium phosphates and sulphates of the alunite supergroup (APS minerals) associated with clay minerals were found in a polymictic Permian granite hosted hydrothermal breccia in the Velence Mts. (Hungary). The mineral assemblage was studied with TEM, XRD, EMPA and FTIR with the aim of revealing the formation conditions and the genetic link to the hydrothermal processes that affected the granite host. Two breccia types were identified in the granite. In a polymictic, strongly silicified breccia type zoned plumbogummite was found in association with rolled tube-shaped halloysite and kaolinite. Calcium, barium and lead zonation of the plumbogummite and the Cl and S contents of the halloysite indicate the hypogene origin of this assemblage. Kaolinite, halloysite and plumbogummite form under acidic conditions at temperatures ≤150 °C in hydrothermal systems. APS minerals belonging to the woodhouseite solid solution series (s.s.s.) were detected in the matrix of argillic polymictic breccia beside the alunite in a kaolinite/dickite, illite rich matrix. Alunite and woodhouseite form under acidic conditions in hydrothermal systems. Kaolinite/dickite and illite also suggest acidic conditions and temperatures of ≥240 °C. The close vicinity of the studied breccias to hydrothermal centres hosted by Palaeogene andesitic volcanic series, the strike of the studied breccia veins as well as the similarities in the mineral assemblages imply that the brecciation is spatially and genetically related to the high-sulfidation epithermal systems of the Palaeogene magmatic-hydrothermal activity. In our model, strongly acidic and hot hydrothermal fluids entered into the granite along E-W trending faults that resulted in silicification, brecciation and the formation of APS minerals in association with clay mineral assemblages.
      PubDate: 2019-04-01
      DOI: 10.1007/s00710-018-0644-1
       
  • Kruijenite, Ca 4 Al 4 (SO 4 )F 2 (OH) 16 ·2H 2 O, a new mineral with
           microporous structure from the Eifel paleovolcanic region, Germany
    • Abstract: Abstract The new mineral kruijenite, ideally Ca4Al4(SO4)F2(OH)16·2H2O, was found in a calcic xenolith from tephra of the Feuerberg paleovolcano situated near Daun, Eifel paleovolcanic region, Rhineland-Palatinate, Germany. It is associated with fluorite, calcite, aragonite, cuspidine, magnesioferrite, hematite, sharyginite, harmunite, and an insufficiently investigated hydrous Ca-Mg-Al silicate. Kruijenite occurs as pale greenish-yellow to colourless long prismatic tetragonal crystals up to 0.1 mm × 1 mm in cavities typically combined in radiating or random aggregates. The mineral is brittle, with Mohs’ hardness of 3; Dcalc is 2.573 g/cm3. The IR spectrum is given. Kruijenite is optically uniaxial (−), ω = 1.576(3), ε = 1.561(3). The chemical composition (wavelength dispersive spectrometer Oxford INCA Wave 700 EPMA analyser, H2O calculated from structural data) is: CaO 32.38 wt%, Al2O3 27.75 wt%, Cr2O3 1.45 wt%, SO3 8.09 wt%, F 5.84 wt%, H2O 25.64 wt%, –O=F –2.46 wt%, total 98.69 wt%. The empirical formula is Ca4.00(Al3.77Cr0.13)Σ3.90(SO4)0.70F2.13(OH)16.17·1.79H2O (Z = 2). Kruijenite is tetragonal, space group P4/ncc, a = 12.9299(4) Å, c = 5.2791(3) Å, V = 882.57(6) Å3, Z = 2. The crystal structure was solved and refined to R = 0.121. Kruijenite represents a novel structure type. Its structure is based on the microporous pseudo-framework built by Al(OH)6 octahedra and CaF2(OH)6 polyhedra. The strongest reflections of the powder X-ray diffraction pattern [d (I) (hkl)] are: 9.12 Å (77%) (110), 4.565 Å (100%) (220), 4.084 Å (50%) (310), 2.964 Å (74%) (321), 2.694 Å (27%) (411), 2.321 Å (24%) (431), 2.284 Å (29%) (511), 2.217 Å (22%) (321, 530), 1.971 Å (40%) (611). The mineral is named in honor of the Dutch collector of Eifel minerals Fred Kruijen (born in 1956).
      PubDate: 2019-04-01
      DOI: 10.1007/s00710-019-00653-3
       
  • Murashkoite, FeP, a new terrestrial phosphide from pyrometamorphic rocks
           of the Hatrurim Formation, South Levant
    • Abstract: Abstract Murashkoite, FeP, is a new mineral found in pyrometamorphic rocks of the Hatrurim Formation, South Levant. It is a typical accessory phase in the marbles and paralavas in the southern Negev Desert, Israel and on the Transjordan Plateau, Jordan. Murashkoite occurs as grains and aggregates up to 2 mm closely associated with barringerite, (Fe,Ni)2P, and zuktamrurite, FeP2. The rock-forming minerals include pyroxenes of the diopside-hedenbergite series, anorthite with subordinate gehlenite, tridymite, cristobalite, pyrrhotite, fluorapatite, chromite, magnetite, hematite, merrillite and late hydrothermal carbonates, silicates and sulfates. Macroscopically, murashkoite is yellowish-grey in colour and has a metallic lustre. In reflected light, the mineral is white with a beige tint and it is non-pleochroic. The anisotropy is distinct, from yellow-grey to greyish-blue. Selected reflectance values [Rmax–Rmin, % (λ, nm)] are: 42.7–40.8 (400), 42.0–40.6 (500), 44.5–43.4 (600), 48.0–47.7 (700). It is brittle. VHN20 = 468 kg mm−2. The holotype material has the chemical composition (electron microprobe): Fe 63.82; Ni 0.88; P 35.56; total 100.26 wt.%. The empirical formula calculated on the basis of 2 apfu is (Fe0.99Ni0.01)1.00P1.00 corresponding to FeP. Murashkoite is orthorhombic, space group Pnma, unit cell parameters refined from the single-crystal data are: a 5.099(2), b 3.251(2), c 5.695(2) Å, V 94.41(8) Å3, Z = 4, Dx = 6.108(5) g cm−3. The crystal structure was solved and refined to R1 = 0.0305 on the basis of 131 unique reflections with I > 2σ(I). The strongest lines of the powder X-ray diffraction pattern [(d, Å) (I, %) (hkl)]: 2.831(75)(002,011); 2.548(22)(200); 2.477(46)(102,111); 1.975(47)(112); 1.895(100)(202,211); 1.779(19)(103); 1.632(45)(013,301,020). The mineral is named in honour of Dr. Mikhail Nikolaevich Murashko (born 1952), for his contributions to the mineralogy of the Hatrurim Formation. Murashkoite is a natural counterpart of synthetic FeP, the compound widely used in heterogeneous catalysis and electrocatalysis.
      PubDate: 2019-04-01
      DOI: 10.1007/s00710-018-0647-y
       
  • Crystal chemistry of dorrite from the Eifel volcanic region, Germany, and
           chemical variations in the khesinite-dorrite-rhönite-kuratite
           solid-solution system
    • Abstract: Abstract Dorrite, khesinite and rhönite from metamorphosed calcic xenoliths of the Bellerberg paleovolcano (Eifel, Germany) were studied, including first determination of the crystal structure of natural dorrite (R = 0.0636). Dorrite is triclinic, P-1, unit-cell parameters are: a = 10.4316(7), b = 10.8236(9), c = 8.9488(7) Å, α = 105.972(6), β = 96.003(9), γ = 124.67(10)° and V = 754.10(11) Å3. Its crystal-chemical formula is (Z = 1): M8Ca2M9Ca2M1Fe3 + M2Fe3 + M3(Fe3+0.8Mg0.2)2M4(Fe3+0.8Mg0.2)2M5(Mg0.9Fe3+0.1)2M6(Mg0.5Fe3+0.5)2M7(Fe3+0.9Al0.1)2[T1(Al0.75Si0.20Fe3+0.05)2T2(Al0.77Si0.20Fe3+0.03)2T3(Al0.9Fe3+0.1)2T4Si2T5(Fe3+0.6Al0.4)2T6(Fe3+0.6Al0.4)2]O40. New and earlier published data show that khesinite, dorrite, rhönite and kuratite form a solid-solution system without significant gaps. The chemical variation and isomorphous substitutions in this system are discussed and the following simplified formulae are suggested: dorrite, Ca2(Fe3+,Mg)5Mg[(Al,Fe3+,Si)5SiO20], khesinite, Ca2(Fe3+,Mg)5Mg[(Fe3+,Al,Si)5SiO20], and rhönite, Ca2(Mg,Fe3+)5Ti[(Si,Al)6O20].
      PubDate: 2019-04-01
      DOI: 10.1007/s00710-018-0645-0
       
  • Advanced mineral characterization and petrographic analysis by μ-EDXRF,
           LIBS, HSI and hyperspectral data merging
    • Abstract: Abstract Petrography and mineralogy are fundamental for understanding processes in various geoscientific fields. Plutonic rock nomenclature is based on mineralogical composition. Therefore, identifying and quantifying minerals is a key for plutonic rock classification. To accomplish this, novel advancements in instrumentations, such as energy dispersive x-ray fluorescence mapping (μ-EDXRF) or hyperspectral imaging (HSI) provide fast and non-destructively spatially resolved and large-scale chemical information. This work describes a comprehensive approach to combine chemical, mineralogical and textural information from μ-EDXRF, Laser Induced Breakdown Spectroscopy (LIBS) and HSI for petrographic analysis of plutonic rocks. Using supervised classification of spectral information, mineral distribution maps are obtained for image analysis including geometrical data of each grain, such as grain size, grain orientation and grain location for subsequent targeted analysis and the modal mineralogy for plutonic rock classification in a QAPF-diagram for 20 rock slabs. The combination of the three mapping techniques can provide valuable information within the limit of each technique such as of spatial resolution or element sensitivity, but with little time needed for sample preparation and measurement. In general, it is an objective, repeatable and quantifiable way for modal mineralogy and petrographic image analysis.
      PubDate: 2019-03-15
      DOI: 10.1007/s00710-019-00657-z
       
  • Protracted fluid-metasomatism of the Siberian diamondiferous
           subcontinental lithospheric mantle as recorded in coated, cloudy and
           monocrystalline diamonds
    • Abstract: Abstract Five typical coated diamonds (from Udachnaya, Yubileynaya, and Aikhal kimberlite pipes) with untypically low microinclusion abundances and four monocrystalline diamonds (Udachnaya, Mir, Nyurbinskaya pipes) that exhibit thin intermediate microinclusion-bearing zones were examined in details for growth structures, characteristic infrared absorption and photoluminescence, and composition of microinclusions. The internal structures of diamonds of both types imply that fluid inclusions entrapment in diamonds does not necessarily relate to the terminal stage of rapid fibrous growth. Instead, nitrogen aggregation state in some diamonds showed that both fibrous coats and inclusion-bearing layers might experience an annealing during mantle residence long enough to pre-date the ultimate kimberlite eruption, whereas the diamonds with internal inclusion-bearing zones also experienced later protracted history of monocrystalline growth. The presence of chloride-carbonate-silicate fluids/melts in monocrystalline diamonds indicate their generation from media generally similar to that observed in some fibrous diamonds. However, the composition of these metasomatizing fluids is different for the mantle beneath Udachnaya (mostly carbonatitic) and other pipes (Aikhal, Yubileynaya, Mir; variable abundance of silicic high-density fluids). The abundance of silica-rich fluids record either a heterogeneous distribution of eclogites in the subcontinental lithospheric mantle, or the operation of silica-rich slab-derived fluids. The inclusion abundance as well as the type of growth (fibrous or monocrystalline) is considered to be controlled by the volume of fluid fluxes; in this case, fluid consumption leads to decreasing growth rates, diminishing inclusion entrainment and stability of layered octahedrons. The detected minor compositional variations of high-density fluids in these diamonds may be due to local scale thermal perturbation in the host source and/or limited chemical heterogeneity of the parental fluid. The high amount of chlorides in high-density fluids from monocrystalline diamonds provide a new evidence for compositions of fluids/melts acting as primary metasomatic agent in the deep mantle of Siberian craton.
      PubDate: 2019-03-13
      DOI: 10.1007/s00710-019-00656-0
       
  • The origin of the carbonate-hosted Huize Zn–Pb–Ag deposit, Yunnan
           province, SW China: constraints from the trace element and sulfur isotopic
           compositions of pyrite
    • Abstract: Abstract The Huize Zn–Pb–Ag deposit in SW China has an ore reserve in excess of 5 Mt. with an ore grade of ≥25 wt% Zn + Pb and 46–100 g/t Ag. This deposit is hosted in Carboniferous dolostone and limestone. Sulfide mineralization is dominated by sphalerite, galena, and pyrite. Four types of pyrite (Py1 to Py4) are temporally and spatially related to mineralization distinguished on the basis of textural features and mineral associations. Pyrite 1 to 3 corresponds to the pyrite-sphalerite sub-stage, whereas Py4 corresponds to sphalerite-galena-pyrite sub-stage. Pyrite 1 shows zoned texture composed of an inclusion-rich core and an inclusion-free rim, whereas Py2, Py3, and Py4 show replacement relic or overgrowth textures. The zoned texture in Py1 was formed by multiple stages of ore fluids, whereas replacement relic texture in Py2 to Py4 was formed by replacement of pyrite by late Pb-Zn-rich fluids. Trace element variation in pyrite results from a combination of mineral inclusions, co-precipitating minerals, and various fluid compositions. Sphalerite, pyrite, and galena have δ34S values of 10.4–23.5‰, suggesting that sulfur was probably derived from the thermochemical reduction of marine sulfates. The Huize pyrite has Co and Ni concentrations (0.02–9.5 ppm and 0.08–143 ppm, respectively) and Co/Ni ratios (~0.01–2.63) similar to pyrite from sedimentary exhalative deposits, submarine hydrothermal vents, and sedimentary pyrite, which may be due to pyrite precipitation from low-temperature (<~250 °C), basin brines or seawater. The Co/Ni ratios of the Huize pyrite are lower than those (~0.2–7.2) of pyrite from Mississippi Valley-type Zn-Pb deposits. The Huize pyrite has Co and Ni contents lower than those associated with volcanogenic massive sulfide, iron oxide copper gold, and porphyry Cu deposits, arguing against the involvement of a magmatic/volcanic component and a direct genetic link between Permian Emeishan basalts and Pb-Zn mineralization. Combining with fluid inclusion temperatures and silver grade, we define the Huize deposit as a transitional type between Mississippi Valley-type and high-temperature carbonate-replacement Zn-Pb deposits.
      PubDate: 2019-03-08
      DOI: 10.1007/s00710-019-00654-2
       
  • Mineral textures of olivine minette and their significance for
           crystallization history of parental magma; an example from the Moldanubian
           Zone (the Bohemian Massif)
    • Abstract: Abstract One of the best-preserved dykes of olivine minette among the lamprophyre dyke swarm in the Moldanubian Zone of the Bohemian Massif (Czech Republic) was investigated. The minette, exposed at Horní Kožlí Village (near Prachatice town), has porphyric texture with phenocrysts of olivine, clinopyroxene, orthopyroxene and biotite in a fine-grained matrix consisting of K-feldspar, biotite, clinopyroxene and minor plagioclase and quartz. Accessory minerals are apatite, Cr-rich spinel and iron sulphides. Olivine is mostly replaced by talc and rimmed by two zones (coronas) – a talc-rich inner zone and a biotite-rich outer zone. Rarely, larger grains of quartz with a corona of clinopyroxene are present. The clinopyroxene grows mostly perpendicular to the quartz rim and radially penetrates the quartz crystal. Three stages of mineral crystallization were distinguished. The first stage with apatite, olivine, biotite, spinel, orthopyroxene and part of the clinopyroxene occurred in the mantle position. During the second stage, felsic phases (K-feldspar, plagioclase, quartz) in the matrix were crystallized. The enrichment of the residual melt by silica and Na occurred as the result of both fractionation and contamination during magma ascent through the granulite facies crust during post-collision orogeny in the Bohemian Massif. Minerals related to the third stage were formed during filling of the vesicles (quartz with reaction rims of clinopyroxene) and subsequent alteration (talc after olivine). The origin of quartz with clinopyroxene reaction rims (‘quartz ocelli’) is explained by filling of cavities formed by the escape of volatiles.
      PubDate: 2019-03-05
      DOI: 10.1007/s00710-019-00658-y
       
  • Early-Middle Ordovician intermediate-mafic and ultramafic rocks in central
           Jilin Province, NE China: geochronology, origin, and tectonic implications
           
    • Abstract: Abstract Magmatic and metasomatic rock suites can be commonly found in active convergent margins as the suprasubduction zone mantle wedge is usually impregnated by melts and fluids. Here we present petrologic, whole-rock geochemical and zircon U-Pb and Lu-Hf data from metamorphic intermediate-mafic and ultramafic rocks in central Jilin Province, NE China, to constrain the Early Paleozoic tectonic evolution of the southeastern margin of the Xing’an-Mongolia Orogenic Belt. Lithologically, the meta-igneous rocks are composed of plagioclase-actinolite, meta-allgovite, tremolitized pyroxenite, and serpentinized peridotite. Geochronological results indicate that the protoliths of the meta-igneous rocks formed during the Early–Middle Ordovician (474–466 Ma). Geochemical features suggest that the rocks are calc-alkaline and transitional-series rocks relatively enriched in large-ion lithophile and light rare earth elements and depleted in high field strength and heavy rare earth elements, implying that they formed in a supra-subduction zone environment. Additionally, the protoliths of the plagioclase-actinolites, which display an affinity for sanukites, resulted from an equilibrium reaction between mantle peridotite and slab melts derived from the partial melting of subducting sediments during early-stage subduction; the meta-allgovite rocks were likely derived from a juvenile depleted lithospheric mantle that was metasomatized by subduction-related fluids; the ultramafic rocks are magmatic cumulates formed in a suprasubduction zone mantle wedge. Furthermore, the meta-allgovite rocks display both arc-like and MORB-like geochemical characteristics, suggesting an intra-continental back-arc basin setting. These features, combined with the presence of the abundance of zircon xenocrysts with Neoproterozoic–Paleozoic ages, as well as the results of previous studies, reflect that a small-scale and limited back-arc basin, which was related to the northward subduction of the Paleo-Asian oceanic plate, probably existed close to the Songnen-Zhangguangcai Range Massif during the Early–Middle Ordovician.
      PubDate: 2019-02-26
      DOI: 10.1007/s00710-019-00655-1
       
  • Petrology and phase equilibrium modeling of granulites from Obudu in the
           Benin-Nigerian Shield, Southeastern Nigeria: implications for clockwise
           P-T evolution in a collisional orogen
    • Abstract: Abstract The Eastern Nigerian terrane forms the eastern flank of the Trans-Saharan Orogenic Belt within the Benin-Nigerian Shield. We report new petrological and P–T data of metamorphic rocks (migmatitic gneisses with subordinate granite gneiss, meta-quartz diorite, and meta-ultramafic rock) from Obudu in the southeastern flank of the Benin-Nigerian Shield for unraveling the tectono-metamorphic signatures of the eastern margin of the Trans-Saharan Orogenic Belt. The migmatized pelitic gneiss contains a peak mineral assemblage of plagioclase + rutile + garnet + biotite + K-feldspar + quartz ± liquid, based on which the peak metamorphic conditions are constrained as 850–890 °C and 9–10 kbar using phase equilibria modeling, optimal thermobarometry, and garnet-biotite geothermometry. Retrograde conditions were also estimated for a plagioclase + quartz + garnet + biotite + cordierite + rutile + sillimanite assemblage as 3.8 kbar/590 °C to 6.8 kbar/780 °C. The peak condition under granulite facies confirmed a marked increase of metamorphic grade from the greenschist facies in the western Benin-Nigerian Shield through the middle-upper amphibolite facies in the north-central Nigerian terranes to the granulite facies in the eastern part of the Benin-Nigerian Block. The results presented in this study are the first evidence of granulite-facies metamorphism from the easternmost parts of the Benin-Nigerian Shield. The clockwise path obtained in this study might suggest a continent-continent collisional setting for the evolution of this region related to the closure of the Goiás-Pharusian Ocean and the formation of the Trans-Saharan Orogenic Belt.
      PubDate: 2019-02-13
      DOI: 10.1007/s00710-019-00652-4
       
  • Magmatic and tectonic setting of the Permian Au mineralization in the
           Xing-Meng Orogenic Belt: constraints from the U–Pb ages, Hf–O isotopes
           and geochemistry of granitic intrusions in the Bilihe and Hadamiao gold
           deposits
    • Abstract: Abstract The Xing-Meng Orogenic Belt (XMOB) hosts significant Au-dominant polymetallic mineral deposits. Although these deposits mostly formed in the Mesozoic, Permian Au deposits are also present but less well studied. In the Bilihe and Hadamiao gold mining areas, granitic intrusions that are associated with gold mineralization were dated by LA–ICP–MS at 272.7–259.7 Ma. These intrusions consist of granodioritic porphyry and quartz diorite that both represent calc-alkaline metaluminous I-type granites. These granitoids exhibit enrichment in LREEs and LILEs, depletion in HREEs and HFSEs, and low Sr/Y ratios, suggesting that these rocks have an island-arc affinity. The εHf(t) values of the Bilihe granodioritic porphyry and Hadamiao quartz diorite range from −0.3 to +8.9, with TDM2 values ranging from 0.7 to 1.3 Ga, and from +2.5 to +13.5, with TDM2 values ranging from 0.4 to 1.1 Ga, respectively. The zircon δ18O values of the granitic porphyry and quartz diorite range from 6.9 to 7.6‰ and from 5.0 to 6.4‰, respectively. A simple binary Hf–O isotope mixing model shows that the assimilation of 10–15% sediments by MORB could have generated the Bilihe granodioritic porphyry, and that the assimilation of less than 5% sediments by MORB could have generated the Hadamiao quartz diorite. Combined with previous studies of the Late Carboniferous to Permian igneous rocks in the southern region of the XMOB, these new data suggest that the Bilihe and Hadamiao ore-related intrusive rocks formed in a continental-arc setting associated with the subduction of the Paleo-Asian oceanic slab. This setting indicates the potential existence of subduction-related gold deposits that are related to contemporaneous igneous activity.
      PubDate: 2019-02-01
      DOI: 10.1007/s00710-018-0638-z
       
  • Mantle source heterogeneity in subduction zones: constraints from
           elemental and isotope (Sr, Nd, and Pb) data on Vulcano Island, Aeolian
           Archipelago, Italy
    • Abstract: Abstract Vulcano is part of the Aeolian volcanic arc in the southern Tyrrhenian Sea. Its products were emplaced through multiple episodes of edifice building and collapse since about 120 ka B.P. to present. A major discontinuity in the activity occurred after about 28 ka, while the focus of volcanism moved from SE to NW. The older products are basalts to shoshonites, and have lower K2O than the younger ones, shoshonites to rhyolites. Between these two groups, Lentia latites-rhyolites, Spiaggia Lunga basalts, and Quadrara shoshonite-trachytes, erupted along the western side of Vulcano Island. The Spiaggia Lunga basalts (i) are the most primitive magmas erupted at Vulcano after 28 ka (ii) mark the change between older and younger phases, and (iii) overlap geochemically with a monzogabbroic intrusion of similar age. This work focuses on the Spiaggia Lunga products, discussed within a large dataset of geochemical and radiogenic isotope analyses on the entire Vulcano sequence. Older products have more primitive geochemical and isotope characteristics, and lower incompatible element contents, than younger ones. The Spiaggia Lunga basalts exhibit intermediate geochemical characteristics between the older and the younger groups, and can likely be regarded as a third magmatic phase, which represents a distinct mantle reservoir active during the magmatic history of Vulcano. Significant variations of Sr, Nd, and Pb isotope ratios, and isotopic disequilibrium between phenocrysts and groundmass, are present among the Vulcano products. This variability suggests crustal assimilation in shallow-level magma chambers, which also accounts for the formation of evolved products by combined assimilation and fractional crystallization, particularly in the younger series. Considering only the mafic products, incompatible element patterns with high LILE/HFSE and enriched signatures of Sr, Nd, and Pb isotope ratios, indicate enriched mantle sources. Besides, chemical and isotope variability among older, younger, and Spiaggia Lunga mafic rocks, suggests an origin from geochemically diverse primary melts, derived from distinct mantle reservoirs. Their parent magmas, based on geochemical and isotope patterns, were from both MORB- and OIB-type mantle sources, subject to variable degrees of metasomatism by subducted sediments.
      PubDate: 2019-02-01
      DOI: 10.1007/s00710-018-0640-5
       
  • Petrogenesis of early cretaceous andesite dykes in the Sulu orogenic belt,
           eastern China
    • Abstract: Abstract This study presents data of in-situ mineral major and trace element chemistry, whole-rock major and trace element and Sr–Nd isotope geochemistry, as well as zircon U–Pb dating and Lu–Hf isotope studies of andesite dykes from the Sulu orogenic belt of eastern China to evaluate their petrogenesis and thus to provide insights into crust–mantle interactions in a tectonic terrane that underwent continental subduction and was then overprinted by oceanic subduction. The andesites mainly comprise plagioclase, hornblende, clinopyroxene and magnetite as phenocrysts that are embedded in a groundmass of fine-grained quartz and K-feldspar, with minor amounts of biotite, magnetite, titanite, apatite and zircon. They possess intermediate concentrations of SiO2 (54.97–62.24 wt.%), Na2O + K2O (6.35–7.24 wt.%) and MgO (3.37–7.12 wt.%) with high Mg# values [Mg# = 100 × Mg/(Mg + Fe2+) molar] of 54–64, and are characterized by arc-like trace element patterns that are enriched in light rare earth elements (LREE) and large ion lithophile elements (LILE) but depleted in high field strength elements (HFSE). The hornblende and clinopyroxene phenocrysts exhibit enrichment in Th and U but an obvious depletion of HFSE. The andesites have high initial 87Sr/86Sr ratios of 0.7073–0.7086 and negative ɛNd(t) values of −15.7 to −14.4 for whole-rock, and newly crystallized magmatic zircons show negative ɛHf(t) values of −27.0 to −17.6. U–Pb dating on syn-magmatic zircons yields consistent ages of 124 ± 2 to 116 ± 1 Ma, indicating eruption of the andesitic lavas during the Early Cretaceous. Inherited zircons are present and yield Neoproterozoic, Paleoproterozoic and Archean U–Pb ages. Taking into account all these geochemical and geochronological data, and the compositional features of contemporaneously formed mafic–andesitic igneous rocks from the Sulu belt and the adjacent continental crust of the North China Craton, we propose that the andesites crystallized from primary andesitic magmas derived from partial melting of enriched metasomatites in the subcontinental lithospheric mantle. The enriched metasomatites are inferred to be formed by a two-step process: firstly by crust–mantle interactions during the Triassic collisional orogeny and secondly by a subsequent modification by fluids/melts that mainly derive from seafloor sediments during subduction of the paleo-Pacific plate in eastern Asia. Slab rollback of the subducted paleo-Pacific slab and concomitant asthenosphere upwelling are an appropriate geodynamic mechanism for the generation of extensive arc-like magmatism during the Early Cretaceous in the Sulu belt.
      PubDate: 2019-02-01
      DOI: 10.1007/s00710-018-0636-1
       
  • Origin and evolution of volatiles in the Central Europe late Variscan
           granitoids, using the example of the Strzegom-Sobótka Massif, SW Poland
    • Abstract: Abstract The results of the new Electron Microprobe Analysis of apatite, hornblende and biotite crystals of the hornblende-biotite variety of the Strzegom-Sobótka granite indicate that these rocks experienced several phases during their evolution. During the first phase, the melting of the continental crust was caused by heating from basaltic magma. Nevertheless, the system was closed, and there is no evidence of the influence of any mafic component. The volatile compositions of apatite crystals recorded the signature of this phase. Afterwards, small quantities of mafic material were delivered into the crystallizing melt by ascending basaltic magma. The volatile composition of hornblende, together with dramatic changes in the F/Cl ratios between apatite and hornblende, indicates that the injection of mafic material occurred between the crystallization of both minerals. During the crystallization of hornblende, the system was closed. During the last episode, the volatile composition recorded by biotite indicates that the system opened again. This is represented by the decrease of Cl in the melt. Moreover, the estimated F concentrations in the melt range from ~2000 to ~3000 ppm and do not change significantly within the crystallization interval, whereas the Cl concentrations decreased from 1470-900 ppm at 829-768 °C to as low as 100 ppm at 710-650 °C, most likely due to the continuous exsolution of aqueous fluid from silicate melt or the crystallization of Cl-bearing minerals.
      PubDate: 2019-02-01
      DOI: 10.1007/s00710-018-0615-6
       
  • Shaw meteorite: water-poor and water-rich melt inclusions in olivine and
           enstatite
    • Abstract: Abstract During the petrological examination of a double polished thick section of the light-colored lithology of the Shaw meteorite, small melt inclusions, typically with diameters between 10 and 35 μm, were discovered in olivine and orthopyroxene crystals. These inclusions represent two different types of melt inclusions, one low in water (0.57% (g/g)) and the other with extremely high concentrations (15% (g/g)). Extremely water-rich inclusions were also found in olivine, which showed bulk water concentration is between 12 and 13% (g/g). Given the high D2O-concentration of (556 ± 47) ppm and a D/H ratio of (337 ± 32 × 10−6) in the glass phase of the water-rich melt inclusions terrestrial contamination can be excluded. Given the bulk water concentration of the Shaw meteorite is about 1%, typical of L-group chondrites, we propose that the high water concentrations found in some melt inclusions was injected into the melt from a melted projectile during an impact event. As the projectile a Cl-type chondrite with high water concentration is highly probable.
      PubDate: 2019-02-01
      DOI: 10.1007/s00710-018-0598-3
       
 
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