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Ziminaite,Fe3+VO4, a new howardevansite-group mineral from the Bezymyannyi volcano,Kamchatka, Russia
Pekov Igor V. Siidra Oleg I. Yapaskurt Vasiliy O. Polekhovsky Yury S. Kartashov Pavel M. 《Mineralogy and Petrology》2018,112(3):371-379
Mineralogy and Petrology - The new mineral ziminaite, ideally Fe3+VO4, was found in fumarole sublimates at the Bezymyannyi volcano, Kamchatka, Russia. Ziminaite occurs as lamellar, tabular or... 相似文献
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Lyudmila V. Malakhova Viktor N. Egorov Tatiana V. Malakhova Sergey B. Gulin Yury G. Artemov 《Geo-Marine Letters》2010,30(3-4):391-398
Concentrations of dissolved methane in seawater and bottom sediments, as well as of methane emanating from gas seeps were measured at 18 stations including several small bays in the Sevastopol coastal area (Black Sea) during 2007–2008. Methane concentrations in surface waters ranged from 10 to 2,970 nmol l?1, and correlated well with values recorded for sediments. Methane concentrations in the water column were influenced by water depth, as well as by air and water temperatures. In the spring and summer of 2008, in situ CH4 saturation relative to air was in the range of 970–71,900%. Maximum saturation was in summer. CH4 fluxes to the atmosphere from the Sevastopol coastal area were estimated to vary from 190 to 1,550 μmol m?2 day?1. Gas bubbles escaping from the seepages contained about 57 vol% methane. Radiocarbon dating of the methane revealed an age not exceeding 150 years, implying a biogenic origin. 相似文献
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Alexander G. Sokol Yury N. Palyanov Igor N. Kupriyanov Mariya P. Polovinka 《Geochimica et cosmochimica acta》2010,74(16):4793-4806
High pressure experiments have been performed in the systems Mg2SiO4-C-O-H and Mg2SiO4-K2CO3-C at 6.3 GPa and 1200 to 1600 °C using a split-sphere multi-anvil apparatus. In the Mg2SiO4-C-O-H system the composition of fluid was modeled by adding different amounts of water and stearic acid. The fO2 was controlled by the Mo-MoO2 or Fe-FeO oxygen buffers. Several experiments in the Mg2SiO4-C-O-H system and all experiments in the Mg2SiO4-K2CO3-C system have been conducted without buffering the fO2. Forsterite in the system Mg2SiO4-K2CO3-C does not reveal OH absorption bands in the IR spectra, while forsterite coexisting with carbon-bearing fluid and silicate melt at logfO2 from FMQ-2 to FMQ-5 (from 2 to 5 log units below fayalite-magnetite-quartz oxygen buffer) contains 800-1850 wt. ppm H2O. The maximum concentrations were detected at 1400 °C and FMQ-3.5. We observed an increase in the solidus temperature in the system Mg2SiO4-C-O-H from 1200 to above 1600 °C with log fO2 decreasing from FMQ-2 to FMQ-5. The increase of the solidus temperature and the broadening of the stability field of the H2O-H2-CH4 subsolidus fluid phase at 1400-1600 °C explain the high H2O storage capacity of forsterite relative to that crystallized from carbon-free, oxidized, hydrous, silicic melt. At temperatures above 1400 °C liquidus forsterite precipitated along with diamond from oxidized (FMQ-1) carbonate-silicate melt and from silicate melt dissolving the moderately reduced C-O-H fluid (from FMQ-2 to FMQ-3.5). Formation of diamond was not detected under ultra-reduced conditions (FMQ-5) at 1200-1600 °C. Olivine co-precipitating with diamond from dry carbonate-silicate or hydrous-silicic fluid/melt can provide information on the H2O contents and speciation of the diamond-forming media in the mantle. The conditions for minimum post-crystallization alteration of olivine and its hydrogen content are discussed. 相似文献
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Alexander G. Sokol Galina A. Palyanova Yury N. Palyanov Anatoly A. Tomilenko Vasiliy N. Melenevsky 《Geochimica et cosmochimica acta》2009,73(19):5820-5834
The composition and potential diamond productivity of C–O–H fluids that could exist in the reduced regions of the Earth’s upper mantle and in the mantles of Uranus and Neptune were studied in experiments at 6.3 GPa and 1400–1600 °C and durations of 15–48 h. Hydrogen fugacity in the fluid phase was controlled by the Mo–MoO2 or Fe–FeO buffers, using a specially modified double-capsule method. The oxygen fugacity in the samples was controlled by adding different amounts of water, stearic acid, anthracene, and docosane to a graphite charge. At high P–T conditions, the degree of decomposition of the heavy hydrocarbons added to the charge was 99.9%. The composition of the fluids coexisting with graphite/diamond in the buffered experiments varied from H2O H2 > CH4 (at fO2 somewhat lower than the “water maximum”) to H2 > CH4 > (C2H4 + C2H6)>C3H8 (in C–H system). In the C–H system the maximum concentrations of major species in the synthesized fluid were: H2 = 79 mol.% and CH4 = 21 mol.%. The composition of the H2-rich fluids, which were synthesized at 6.3 GPa and 1400–1600 °C for the first time, differs considerably from that of the ultra-reduced CH4-rich fluids stable at 2.0–3.5 GPa and 1000–1300 °C. Thermodynamic calculations of the reduced C–O–H fluids at the P–T conditions of the experiments revealed CH4-rich compositions (CH4 H2 > (C2H4 + C2H6)>C3H8), which however drastically differed from the synthesized compositions. The rates of diamond nucleation and growth in the experiments depended on the fluid composition. Diamond crystallization had a maximum intensity in the pure aqueous fluids, while in the H2-rich fluids no diamond formation was observed. Only metastable graphite precipitated from the ultra-reduced fluids. The type of the initial hydrocarbon used for the fluid generation did not affect this process. 相似文献
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Victor G. Kornilov Vladimir M. Lipunov Evgeny S. Gorbovskoy Aleksander A. Belinski Dmitry A. Kuvshinov Natalia V. Tyurina Nikolai I. Shatsky Anatoly V. Sankovich Aleksander V. Krylov Pavel V. Balanutsa Vadim V. Chazov Artem S. Kuznetsov Dmitry S. Zimnuhov Victor A. Senik Andrey G. Tlatov Aleksander V. Parkhomenko Denis V. Dormidontov Vadim V. Krushinsky Ivan S. Zalozhnyh Aleksander A. Popov Sergey A. Yazev Nikolai M. Budnev Kirill I. Ivanov Evgeny N. Konstantinov Oleg A. Gress Oleg V. Chvalaev Vladimir V. Yurkov Yury P. Sergienko Irina P. Kudelina 《Experimental Astronomy》2012,33(1):173-196
Presented paper describes the basic principles and features of the implementation of a robotic network of optical telescopes MASTER, designed to study the prompt (simultaneous with gamma radiation) optical emission of gamma-ray bursts and to perform the sky survey to detect unknown objects and transient phenomena. With joint efforts of Sternberg astronomical institute, High altitude astronomical station of the Pulkovo observatory, Ural state university, Irkutsk state university, Blagoveshchensk pedagogical university, the robotic telescopes MASTER?II near Kislovodsk, Yekaterinburg, Irkutsk and Blagoveshchensk were installed and tested. The network spread over the longitudes is greater than 6?h. A further expansion of the network is considered. 相似文献
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Alexander?G.?SokolEmail authorView author&#;s OrcID profile Alexey?N.?Kruk Yury?N.?Palyanov Nikolay?V.?Sobolev 《Contributions to Mineralogy and Petrology》2017,172(4):21
Hydrous K-rich kimberlite-like systems are studied experimentally at 5.5–7.5 GPa and 1200–1450?°C in terms of phase relations and conditions for formation and stability of phlogopite. The starting samples are phlogopite–carbonatite–phlogopite sandwiches and harzburgite–carbonatite mixtures consisting of Ol?+?Grt?+?Cpx?+?L (±Opx), according to the previous experimental results obtained at the same P–T parameters but in water-free systems. Carbonatite is represented by a K- and Ca-rich composition that may form at the top of a slab. In the presence of carbonatitic melt, phlogopite can partly melt in a peritectic reaction at 5.5 GPa and 1200–1350?°C, as well as at 6.3–7.0 GPa and 1200?°C: 2Phl?+?CaCO3 (L)?Cpx?+?Ol?+?Grt?+?K2CO3 (L)?+?2H2O (L). Synthesis of phlogopite at 5.5 GPa and 1200–1350?°C, with an initial mixture of H2O-bearing harzburgite and carbonatite, demonstrates experimentally that equilibrium in this reaction can be shifted from right to left. Therefore, phlogopite can equilibrate with ultrapotassic carbonate–silicate melts in a?≥?150?°C region between 1200 and 1350?°C at 5.5 GPa. On the other hand, it can exist but cannot nucleate spontaneously and crystallize in the presence of such melts in quite a large pressure range in experiments at 6.3–7.0 GPa and 1200?°C. Thus, phlogopite can result from metasomatism of peridotite at the base of continental lithospheric mantle (CLM) by ultrapotassic carbonatite agents at depths shallower than 180–195 km, which creates a mechanism of water retaining in CLM. Kimberlite formation can begin at 5.5 GPa and 1350?°C in a phlogopite-bearing peridotite source generating a hydrous carbonate–silicate melt with 10–15 wt% SiO2, Ca# from 45 to 60, and high K enrichment. Upon further heating to 1450?°C due to the effect of a mantle plume at the CLM base, phlogopite disappears and a kimberlite-like melt forms with SiO2 to 20 wt% and Ca#?=?35–40. 相似文献
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Paul R. J. Saey Clemens Schlosser Pascal Achim Matthias Auer Anders Axelsson Andreas Becker Xavier Blanchard Guy Brachet Luis Cella Lars-Erik De Geer Martin B. Kalinowski Gilbert Le Petit Jenny Peterson Vladimir Popov Yury Popov Anders Ringbom Hartmut Sartorius Thomas Taffary Matthias Zähringer 《Pure and Applied Geophysics》2010,167(4-5):499-515
Activity concentration data from ambient radioxenon measurements in ground level air, which were carried out in Europe in the framework of the International Noble Gas Experiment (INGE) in support of the development and build-up of a radioxenon monitoring network for the Comprehensive Nuclear-Test-Ban Treaty verification regime are presented and discussed. Six measurement stations provided data from 5 years of measurements performed between 2003 and 2008: Longyearbyen (Spitsbergen, Norway), Stockholm (Sweden), Dubna (Russian Federation), Schauinsland Mountain (Germany), Bruyères-le-Châtel and Marseille (both France). The noble gas systems used within the INGE are designed to continuously measure low concentrations of the four radioxenon isotopes which are most relevant for detection of nuclear explosions: 131mXe, 133mXe, 133Xe and 135Xe with a time resolution less than or equal to 24 h and a minimum detectable concentration of 133Xe less than 1 mBq/m3. This European cluster of six stations is particularly interesting because it is highly influenced by a high density of nuclear power reactors and some radiopharmaceutical production facilities. The activity concentrations at the European INGE stations are studied to characterise the influence of civilian releases, to be able to distinguish them from possible nuclear explosions. It was found that the mean activity concentration of the most frequently detected isotope, 133Xe, was 5–20 mBq/m3 within Central Europe where most nuclear installations are situated (Bruyères-le-Châtel and Schauinsland), 1.4–2.4 mBq/m3 just outside that region (Stockholm, Dubna and Marseille) and 0.2 mBq/m3 in the remote polar station of Spitsbergen. No seasonal trends could be observed from the data. Two interesting events have been examined and their source regions have been identified using atmospheric backtracking methods that deploy Lagrangian particle dispersion modelling and inversion techniques. The results are consistent with known releases of a radiopharmaceutical facility. 相似文献
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The Hydrograph model (a distributed process-based model) was applied to the simulation of soil freeze-thaw and runoff processes, to assess the viability of the model approach and the influence of specific environmental factors in a permafrost environment. Three mountainous permafrost watersheds were studied, at the Kolyma Water Balance Station in north-eastern Russia. The watersheds include rocky talus, mountainous tundra and moist larch-forest landscape regimes, and they were modelled at daily time-steps for the period 1971–1984. Simulated results of soil freeze-thaw depth and runoff showed reasonable agreement with observed values. This study reveals and mathematically describes the dependence of surface and subsurface flow on thawing depth and landscape characteristics. Process analysis and modelling in permafrost regions, including ungauged basins, is suggested, with observable properties of landscapes being used as model parameters, combined with an appropriate level of physically based conceptualization. 相似文献
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Sergej A. Kitaigorodskii Yury A. Volkov Andrey A. Grachev 《Boundary-Layer Meteorology》1995,76(1-2):181-197
The aerodynamic classification of the resistance laws above solid surfaces is based on the use of a so-called Reynolds roughness number Re
s =h
s
u
*/, whereh
s is the effective roughness height, -viscosity,u
*-friction velocity. The recent experimental studies reported by Toba and Ebuchi (1991), demonstrated that the observed variability of the sea roughness cannot be explained only on the basis of the classification of aerodynamic conditions of the sea surface proposed by Kitaigorodskii and Volkov (1965) and Kitaigorodskii (1968) even though the latter approach gains some support from recent experimental studies (see for example Geernaertet al. 1986). In this paper, an attempt is made to explain some of the recently observed features of the variability of surface roughness (Toba and Ebuchi, 1991; Donelanet al., 1993). The fluctuating regime of the sea surface roughness is also described. It is shown that the contribution from the dissipation subrange to the variability of the sea surface can be very important and by itself can explain Charnock's (1955) regime. 相似文献