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Nemzeti Kutatasi Fejlesztesi es Innovacios Hivatal (NKFIH); Ramon y Cajal fellowship., Primary multiphase fluid inclusions (MFI) were studied in one eclogite and two granulites from the Cabo Ortegal Complex (COC, NW Spain) by means of Raman imaging, Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) and Focused Ion Beam - Scanning Electron Microscopy (FIB)-SEM. Complementary, secondary MFI in pyroxenites from COC were also investigated. MFI hosted in eclogite and granulites occur along growth zones or in 3D clusters in garnet porphyroblasts suggesting a primary origin at high-pressure (HP) metamorphic conditions. The mineral assemblage of MFI is mainly composed of Fe-Mg-Ca-carbonates and phyllosilicates +/- graphite +/- quartz +/- corundum +/- pyrite +/- apatite +/- rutile and a fluid phase composed of nitrogen +/- methane +/- carbon-dioxide. The mineral proportions vary among the lithologies. Dominant carbonates and hydrous silicates are interpreted as step-daughter minerals (crystals formed in the MFI after entrapment as a result of fluid-host interaction), whereas apatite, quartz and rutile are considered in part as accidentally trapped minerals since they also occur as crystal inclusions together with MFI in each rock type. Quartz and corundum occur together in MFI in ultramafic granulite and are regarded as step-daughter minerals in this lithology. These observations suggest that the MFI are products of post-entrapment reactions of a homogeneous COHN fluid system with the host mineral. Thermodynamic calculations in the CaFMAS-COHN system confirmed that bulk composition of the MFI in eclogite is similar to the host garnet+COHN composition except for a potential lost of H2O. Carbonation and hydration reaction between the host (i.e. garnet or pyroxene) and the fluid inclusion results in the consumption of all CO2 and part of the H2O from the fluid phase producing Ca-Fe-Mg-carbonates and hydrous step-daughter minerals, mostly pyrophyllite and chlorite. Nitrogen content of the originally trapped COHN fluid in eclogite was estimated to have a maximum value of 10 mol% at peak HP conditions and 30-40 mol% at retrograde conditions that is within the range of the observed MFI in the residual fluid (13-68 mol%). Pseudosection modelling confirmed the stability of the phase assemblage in the MFI in a specific low-pressure, low-temperature stability field (between 300 degrees C and 400 degrees C at pressures < 1 GPa), caused by H2O- and CO2-consuming reactions possibly in a single step. Our findings indicate that such processes in the exhuming HP units may play a role in global nitrogen and carbon cycling as well as potentially contributing to nitrogen and methane supply to subsurface-surface environments during devolatilization in the forearc regions of convergent plate margins., National Research, Development & Innovation Office (NRDIO) - Hungary, Spanish Government

Publisher's version (útgefin grein), Oldoinyo Lengai, located in the Gregory Rift in Tanzania, is a world-famous volcano owing to its uniqueness in producing natrocarbonatite melts and because of its extremely high CO2 flux. The volcano is constructed of highly peralkaline [PI = molar (Na2O + K2O)/Al2O3 > 2–3] nephelinite and phonolites, both of which likely coexisted with carbonate melt and a CO2-rich fluid before eruption. Results of a detailed melt inclusion study of the Oldoinyo Lengai nephelinite provide insights into the important role of degassing of CO2-rich vapor in the formation of natrocarbonatite and highly peralkaline nephelinites. Nepheline phenocrysts trapped primary melt inclusions at 750–800 °C, representing an evolved state of the magmas beneath Oldoinyo Lengai. Raman spectroscopy, heating-quenching experiments, low current EDS and EPMA analyses of quenched melt inclusions suggest that at this temperature, a dominantly natritess-normative, F-rich (7–14 wt%) carbonate melt and an extremely peralkaline (PI = 3.2–7.9), iron-rich nephelinite melt coexisted following degassing of a CO2 + H2O-vapor. We furthermore hypothesize that the degassing led to re-equilibration between the melt and liquid phases that remained and involved 1/ mixing between the residual (after degassing) alkali carbonate liquid and an F-rich carbonate melt and 2/ enrichment of the coexisting nephelinite melt in alkalis. We suggest that in the geological past similar processes were responsible for generating highly peralkaline silicate melts in continental rift tectonic settings worldwide., This study was financially supported by project NRDIO ( National Research, Development, and Innovation Office of Hungary ) K-119535 (to M. Berkesi and T. Guzmics) and by the Betta Üzletlánc Ltd. to Guzmics. In addition, M. Berkesi acknowledges to the ELTE Institutional Excellence Program (1783-3/2018/FEKUTSRAT) supported by the Hungarian Ministry of Human Capacities . We thank Toshiaki Tsunogae for his editorial handling, and Alan Cooper and an anonymous reviewer for their constructive comments that helped to improve the manuscript.

The influence of anthropogenic outdoor sources on the geochemical composition of house dust material in large cities is poorly understood. In this study, we investigate the magnetic signature and the concentrations of potentially toxic elements (PTEs) in randomly selected house dust samples from the metropolitan area of Athens, the most populated city in Greece. Environmental magnetic measurements, including isothermal remanent magnetization and thermomagnetism, indicated that the main magnetic mineral is coarse-grained low-coercivity magnetite. Detailed microscopic observations of the magnetically extracted material revealed the presence of three different kinds of Fe-rich particles deriving from both combustion-related and non-exhaust vehicular sources: irregularly-shaped grains and spherules of Fe-oxides, and particles consisting of metallic Fe. Further study of the morphology of single anthropogenic magnetic spherules (size > 30 μm) identified the presence of magnetite spherical particles, typically formed by industrial combustion processes. Enrichment factors (EFs) for the PTEs calculated against the Athens urban soil showed that the house dusts were very highly enriched in Cd, Cu, Zn and significantly enriched in Pb (median EF values of 34.1, 26.2, 25.4 and 10.3, respectively). The oral bioaccessibility of PTEs in the house dust, evaluated using a simulated gastric solution (0.4 M glycine), was in the order Pb > Zn > Mn > Cd > Ni > Cu > Cr > Fe. Concentrations of Pb increased with the house age. Principal component and cluster analysis demonstrated the close association of anthropogenic Cu, Pb and Zn with the magnetic susceptibility of the house dusts. We conclude that both traffic-related and industrial sources trigger the occurrence of magnetic Fe/PTEs- rich particles in house dust. These results reinforce the use of environmental magnetism determinations for assessing anthropogenic contamination of PTEs in the indoor environment in large cities.

Cu nanofoams are promising materials for a variety of applications, including anodes in high-performance lithium-ion batteries. The high specific surface area of these materials supports a high capacity and porous structure that helps accommodate volume expansion which occurs as batteries are charged. One of the most efficient methods to produce Cu nanofoams is the dealloying of Cu alloy precursors. This process often yields nanofoams that have low strength, thus requiring additional heat treatment to improve the mechanical properties of Cu foams. This paper provides the effects of heat treatment on the microstructures, mechanical properties, and electrochemical performance of Cu nanofoams. Annealing was conducted under both inert and oxidizing atmospheres. These studies ultimately reveal the underlying mechanisms of ligament coarsening during heat treatment.

Bjurböle L/LL4 ordinary chondrite was studied using scanning electron microscopy with energy dispersive spectroscopy, Raman spectroscopy, X-ray diffraction, magnetization measurements and Mössbauer spectroscopy. The phase composition and the relative iron fractions in the iron-bearing phases were determined. The unit cell parameters for olivine, orthopyroxene and clinopyroxene are similar to those observed in the other ordinary chondrites. The higher contents of forsterite and enstatite were detected by Raman spectroscopy. Magnetization measurements showed that the temperature of the ferrimagnetic-paramagnetic phase transition in chromite is around 57 K and the saturation magnetic moment is ~7 emu/g. The values of the 57Fe hyperfine parameters for all components in the Bjurböle Mössbauer spectrum were determined and related to the corresponding iron-bearing phases. The relative iron fractions in Bjurböle and the 57Fe hyperfine parameters of olivine, orthopyroxene and troilite were compared with the data obtained for the selected L and LL ordinary chondrites. The Fe2+ occupancies of the M1 and M2 sites in silicate crystals were determined using both X-ray diffraction and Mössbauer spectroscopy. Then, the temperatures of equilibrium cation distribution were determined, using two independent techniques, for olivine as 666 K and 850 K, respectively, and for orthopyroxene as 958 K and 1136 K, respectively. Implications of X-ray diffraction, magnetization measurements and Mössbauer spectroscopy data for the classification of the studied Bjurböle material indicate its composition being close to the LL group of ordinary chondrites. © 2020 Elsevier B.V. 783-3/2018/FEKUTSRAT; 115784, 115913, 134770; Fundação para a Ciência e a Tecnologia, FCT; Academy of Finland: 293975, 325806; Ministry of Education and Science of the Russian Federation, Minobrnauka: FEUZ-2020-0060; Ural Branch, Russian Academy of Sciences, UB RAS: АААА-А19-119071090011-6; Fundació Catalana de Trasplantament, FCT; Government Council on Grants, Russian Federation; Ural Federal University, UrFU; Ministry of Science and Higher Education of the Russian Federation This work was supported by the Ministry of Science and Higher Education of the Russian Federation, project № FEUZ-2020-0060, and Act 211 of the Government of the Russian Federation, contract № 02.A03.21.0006. The Coimbra Chemistry Centre (CQC; research unit UI0313/QUI/2020) is supported by the Portuguese Science Foundation (FCT) and COMPETE-UE. On behalf of two of us (Á.Sz. and Z.D.) this work was completed in the ELTE Excellence Programme (783-3/2018/FEKUTSRAT) supported by the Hungarian Ministry of Human Capacities. E.K. and Z.H. acknowledge NKFIH-OTKA (the grants № 115784, № 115913 and № 134770). M.G. acknowledges insightful discussions with Jarmo Moilanen and the Academy of Finland project № 325806 “Planetary spectrometry”. T.K. acknowledges the Academy of Finland project № 293975. The Zavaritsky Institute of Geology and Geochemistry of the Ural Branch of the Russian Academy of Sciences is supported by the Ministry of Science and Higher Education of the Russian Federation, project № АААА-А19-119071090011-6 (A.A.M.). This work was carried out within the Agreements of Cooperation between the Ural Federal University (Ekaterinburg) and the University of Coimbra (Coimbra) and between the Ural Federal University (Ekaterinburg) and the Eötvös Loránd University (Budapest). This work was supported by the Ministry of Science and Higher Education of the Russian Federation, project ? FEUZ-2020-0060, and Act 211 of the Government of the Russian Federation, contract ? 02.A03.21.0006. The Coimbra Chemistry Centre (CQC; research unit UI0313/QUI/2020) is supported by the Portuguese Science Foundation (FCT) and COMPETE-UE. On behalf of two of us (?.Sz. and Z.D.) this work was completed in the ELTE Excellence Programme (783-3/2018/FEKUTSRAT) supported by the Hungarian Ministry of Human Capacities. E.K. and Z.H. acknowledge NKFIH-OTKA (the grants ? 115784, ? 115913 and ? 134770). M.G. acknowledges insightful discussions with Jarmo Moilanen and the Academy of Finland project ? 325806 ?Planetary spectrometry?. T.K. acknowledges the Academy of Finland project ? 293975. The Zavaritsky Institute of Geology and Geochemistry of the Ural Branch of the Russian Academy of Sciences is supported by the Ministry of Science and Higher Education of the Russian Federation, project ? ????-?19-119071090011-6 (A.A.M.). This work was carried out within the Agreements of Cooperation between the Ural Federal University (Ekaterinburg) and the University of Coimbra (Coimbra) and between the Ural Federal University (Ekaterinburg) and the E?tv?s Lor?nd University (Budapest).

Middle Miocene salinity crisis in the Central Paratethys resulted in significant amounts of marine evaporite deposits in the Transylvanian Basin (TB), Romania. The thickness of salt at Praid area is potentially suitable for underground storage of radioactive waste or gases. One of the main factors that determines the potential usage of this voluminous salt body for storage or disposal of various materials is the microstructural characteristics of the salt rock.Praid is located at the eastern margin of the TB as part of the eastern diapir alignment. The underground salt mine at Praid has been operating there continuously for centuries. It is an ideal place for sampling the internal part of a salt diapir body, where 20 representative samples were collected. The aim of this study is to extend our understanding of the deformation mechanism in the Praid salt rock.Primary and secondary structural features were observed and distinguished through detailed petrographic observation. Two types of salt rock were identified: 1/ massive grey salt with large, elongated halite crystals, containing primary fluid inclusions (FIp), accompanied by submicrometer sized grains of halite and clay matrix, and 2/ layered salt with more uniform grainsize distribution showing alternation of greyish (clay rich) and white (clear halite) layers. The layered rock type has mosaic-like structure with a large number of secondary fluid inclusions (FIs). Beside halite, authigenic anhydrite and dolomite are present subordinately (~ 1 vol. %). Secondary fluid inclusions, composed of nitrogen and methane, are indicators of fluid migration pathways throughout the salt body.Electron Backscatter Diffraction (EBSD) mapping was performed both in the massive and layered salt samples to shed light on the microstructure of the salt rocks. Gamma irradiation was carried as a complementary method of EBSD mapping. Comparing the subgrain diameters obtained from the two techniques, the values are fairly overlapping. The detailed microstructural observations allowed to recognize both dislocation creep and pressure solution processes, which acted concurrently in the Praid salt rock. The differential stress calculations on the salt rock samples indicate a maximum differential stress less than 2 MPa for the massive salt and less than 1.8 MPa for the layered salt. The strain rate calculations (total strain rate between 7.3*e-11 s-1 and 1.8*e-10 s-1) are in good agreement with the observed features in the salt mine, where one of the ~260-year-old salt extraction chambers suffered at least 10 % compressional deformation.The microstructural characters of the salt body reveal a complex deformation history where fluids have played an important role. The results of this project will be useful and comparable with the regional geological knowledge, to better understand the evolution of this Middle Miocene salt body.The project is supported by the Cooperative Doctoral Programme of the Ministry for Innovation and Technology (ITM).

Two new, extremely small land snail species, Angustopila coprologos Páll-Gergely, Jochum & Hunyadi n. sp. and Angustopila psammion Páll-Gergely, Vermeulen & Anker n. sp. are described from northern Vietnam and northern Laos, respectively. The former is characterized by a rough surface sculpture and bears tiny mud granules arranged in a pattern of radial lines on its shell surface. The latter species is the new global record-holder of the tiniest land snail title, with a shell width of 0.6–0.68 mm and a shell height of 0.46–0.57 mm. These measurements surpass the former records of Angustopila pallgergelyi and Acmella nana.

Author(s): Bali, E; Guðfinnsson, GH; Aradi, LE; Szabo, A; Szabo, C; Zierenberg, R; Diamond, LW; Pettke, T; Friðleifsson, G | Abstract: The ∼4500-m-deep Iceland Deep Drilling Project (IDDP) borehole IDDP-2 in Iceland penetrated the root of an active seawater-recharged hydrothermal system below the Mid-Atlantic Ridge. As direct sampling of pristine free fluid was impossible, we used fluid inclusions to constrain the in situ conditions and fluid composition at the bottom of the hydrothermal convection cell. The fluid temperature is ∼600 °C, and its pressure is near-hydrostatic (∼45 MPa). The fluid exists as two separate phases: an H2O-rich vapor (with an enthalpy of ∼59.4 kJ/mol) and an Fe-K–rich brine containing 2000 μg/g Cu, 3.5 μg/g Ag, 1.4 μg/g U, and 0.14 μg/g Au. Occasionally, the fluid inclusions coexist with rhyolite melt inclusions. These findings indicate that the borehole intersected high-energy steam, which is valuable for energy production, and discovered a potentially ore-forming brine. We suggest that similar fluids circulate deep beneath mid-ocean ridges worldwide and form volcanogenic massive sulfide Cu-Zn-Au-Ag ore deposits.

Based on the well-known excellent adsorbent ability of chicken eggshells, the adsorptive capacity and mechanism of Remazol Brilliant Violet-5R (RBV-5R) dye by eggshell was investigated. Exploiting the high surface-area-to-volume ratio and porous structure of this natural adsorbent, the developed procedure showed to be useful for the efficient adsorption of RBV-5R dye from contaminated water. The protocol was thoroughly optimized by investigating the effect of the dye concentration, biomass-contaminated water ratio, particle size of the adsorbent, pH and temperature, as they are key factors in the efficiency of the dye removal process. The eggshell material was characterized by different types of microscopy techniques (stereo, polarization, SEM) as well as elemental analysis (element distribution mapping, EDX), Raman spectroscopy and BET-surface density measurements. EDX, FTIR and Raman spectroscopy proved the presence of the adsorbed dye on the surface of the biomaterial. It was shown that under optimal conditions, the environmentally friendly and inexpensive eggshell could be a reliable adsorbent for Remazol dye removal from wastewater.

Amphibole is one of the most abundant ’water’-bearing minerals in the Earth’s upper mantle. Amphiboles occur as interstitial grains, lamellae within pyroxenes or as daughter minerals within fluid inclusions. Most commonly amphibole formation is related to mantle metasomatism, where the agent has a subducted slab (e.g. Manning 2004) or an asthenospheric origin (e.g. Berkesi et al. 2019). After the formation of fluid inclusions, a subsolidus interaction can take place where the H2O content of fluid inclusions may crystallize pargasite (e.g. Plank et al. 2016).Here we present amphibole lamellae formation in mantle xenoliths from the Persani Mountains Volcanic Field that is interrelated to a reaction between fluid inclusions and host clinopyroxene. Newly formed amphibole lamellae occur only in the surroundings of the fluid inclusions and grow within the host clinopyroxene in a preferred crystallographic direction. Studied lamellae do not reach the rim of the host mineral implying that components needed for formation of amphibole lamellae in clinopyroxene could have only originated from the fluid inclusion itself. We measured the major element composition of amphibole lamellae and host clinopyroxene (1) and used Raman spectroscopy and FIB-SEM on fluid inclusion study situated next to the lamellae (2). Results support the hypothesis that chemical components (dominantly H+) migrated sub-solidus from the fluid inclusion into the host mineral after fluid entrapment via subsolidus interaction. Beyond the clinopyroxene-hosted fluid inclusions, fluid inclusions in orthopyroxenes were also studied as a reference. Our study shows that post-entrapment diffusion from a fluid inclusion into the host mineral changes the solid/fluid ratio of the mantle which could modify the rheology of the lithospheric mantle.Berkesi, M. et al. 2019. Chemical Geology, 508, 182-196.Kovács et al. (2017) Acta Geodaetica et Geophysica, 52(2), 183-204.Manning C. E. 2004. Earth and Planetary Science Letters, 223, 1-16.Plank, T. A. et al. 2016. In AGU Fall Meeting Abstracts.

We report the results of the complex study of the bulk interior of Bursa L6 ordinary chondrite using optical microscopy, scanning electron microscopy with energy dispersive spectroscopy, electron microprobe analysis (EMPA), X-ray diffraction (XRD), magnetization measurements, and Mossbauer spectroscopy. The main and minor iron-bearing phases and their chemical compositions were determined by these techniques. The detected iron-bearing phases in the bulk interior of Bursa L6 are the following: olivine; orthopyroxene; Ca-rich clinopyroxene; troilite; chromite; hercynite; ilmenite; the alpha(2)-Fe(Ni, Co), alpha-Fe(Ni, Co), and gamma-Fe(Ni, Co) phases; and ferrihydrite resulting from meteorite terrestrial weathering. Using the EMPA, the values of fayalite and ferrosilite were obtained as similar to 25.2% and similar to 21.4%, respectively. The unit cell parameters for silicate crystals were determined from XRD, then the Fe2+ and Mg2+ occupations of the M1 and M2 sites in these crystals were estimated. Further calculations of the ratios of the Fe2+ occupancies in the M1 and M2 sites in olivine and orthopyroxene based on XRD and Mossbauer spectroscopy appeared to be in a good agreement. The temperatures of equilibrium cation distributions for olivine and orthopyroxene obtained from these techniques are consistent: 623 K (XRD) and 625 K (Mossbauer spectroscopy) for olivine and 1138 K (XRD) and 1122 K (Mossbauer spectroscopy) for orthopyroxene., Ministry of Science and Higher Education of the Russian Federation [FEUZ-2020-0060, AAAA-A18-118053090045-8, AAAA-A19-119071090011-6]; Act 211 of the Government of the Russian Federation [02.A03.21.0006]; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [MFAG/113F035]; Ege University Scientific Research Projects Coordination UnitEge University [17-FEN-050]; Hungarian Ministry of Human Capacities [783-3/2018/FEKUTSRAT], The authors are grateful to G.A. Yakovlev (Ural Federal University, Ekaterinburg, Russian Federation) for the help with scanning electron microscopy. This work was supported by the Ministry of Science and Higher Education of the Russian Federation, project No FEUZ-2020-0060 and by Act 211 of the Government of the Russian Federation, contract No 02.A03.21.0006. O.U. was supported by the Scientific and Technological Research Council of Turkey (TUBITAK), project No MFAG/113F035 and by the Ege University Scientific Research Projects Coordination Unit, project No 17-FEN-050. D.A.Z. and A.A.M. were supported by the Ministry of Science and Higher Education of the Russian Federation, projects No AAAA-A18-118053090045-8 (D.A.Z.) and No AAAA-A19-119071090011-6 (D.A.Z. and A.A.M.). on behalf of two of us (~ A.Sz. and Z.D.), this work was completed in the ELTE Excellence Programme (783-3/2018/FEKUTSRAT) supported by the Hungarian Ministry of Human Capacities. This work was carried out within the Agreement of Cooperation between the Ural Federal University (Ekaterinburg) and the E_otv_os Lor~and University (Budapest).

The aim of this study was to determine both ‘water’ contents (as OH− and H2O) and δD values of several clinopyroxene samples from alkaline basalts. These parameters were first obtained from five clinopyroxene samples using both the classical ‘off-line’ vacuum extraction technique and the ‘on-line’ high-temperature pyrolysis technique. Blanks measured with the ‘on-line’ gas extraction techniques were low enough to prevent any contamination by atmospheric water vapour. The comparison of data has revealed that our ‘on-line’ procedure is more effective for the extraction of ‘water’ from clinopyroxenes and, consequently, this ‘on-line’ technique was applied to ten additional clinopyroxene samples. Sample δD values cover a similar range from −95 to −45 ‰ (VSMOW) regardless of the studied locations, whereas the total ‘water’ content varies from ~115 to ~2570 ppm. The structural hydroxyl content of clinopyroxene samples measured by micro-FTIR spectrometry varies from ~0 to 476 ppm expressed in molecular water equivalent. The total ‘water’ concentrations determined by mass spectrometry differ considerably from structural hydroxyl contents constrained by micro-FTIR, thus indicating that considerable proportion of the ‘water’ may be present in (nano)-inclusions. The structural hydroxyl concentration—apart from clinopyroxenes separated from amphibole clinopyroxenite xenoliths—correlates positively with the δD values of clinopyroxene megacrysts for each locality, indicating that structurally bond hydrogen in clinopyroxenes may have δD values higher than molecular water in inclusions. This implies that there may be a significant hydrogen isotope fractionation for structural hydroxyl during crystallization of clinopyroxene, while for molecular water there may be no or only negligible isotope fractionation.