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  Subjects -> ENGINEERING (Total: 2003 journals)
    - CHEMICAL ENGINEERING (158 journals)
    - CIVIL ENGINEERING (153 journals)
    - ELECTRICAL ENGINEERING (86 journals)
    - ENGINEERING (1128 journals)
    - ENGINEERING MECHANICS AND MATERIALS (303 journals)
    - HYDRAULIC ENGINEERING (47 journals)
    - INDUSTRIAL ENGINEERING (52 journals)
    - MECHANICAL ENGINEERING (76 journals)

CHEMICAL ENGINEERING (158 journals)                  1 2     

ACS Combinatorial Science     Full-text available via subscription   (Followers: 9)
Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials     Hybrid Journal   (Followers: 4)
Acta Polymerica     Hybrid Journal   (Followers: 6)
Additives for Polymers     Full-text available via subscription   (Followers: 21)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 5)
Advanced Chemical Engineering Research     Open Access   (Followers: 8)
Advanced Powder Technology     Hybrid Journal   (Followers: 12)
Advances in Chemical Engineering     Full-text available via subscription   (Followers: 17)
Advances in Chemical Engineering and Science     Open Access   (Followers: 23)
Advances in Polymer Technology     Hybrid Journal   (Followers: 12)
African Journal of Pure and Applied Chemistry     Open Access   (Followers: 4)
Annual Review of Analytical Chemistry     Full-text available via subscription   (Followers: 9)
Annual Review of Chemical and Biomolecular Engineering     Full-text available via subscription   (Followers: 10)
Anti-Corrosion Methods and Materials     Hybrid Journal   (Followers: 4)
Applied Petrochemical Research     Open Access   (Followers: 3)
Asia-Pacific Journal of Chemical Engineering     Hybrid Journal   (Followers: 6)
Biochemical Engineering Journal     Hybrid Journal   (Followers: 8)
Biomass Conversion and Biorefinery     Partially Free   (Followers: 5)
BMC Chemical Biology     Open Access   (Followers: 4)
Brazilian Journal of Chemical Engineering     Open Access   (Followers: 2)
Bulletin of the Chemical Society of Ethiopia     Open Access   (Followers: 1)
Carbohydrate Polymers     Hybrid Journal   (Followers: 8)
Catalysts     Open Access   (Followers: 7)
Chemical and Materials Engineering     Open Access  
Chemical and Petroleum Engineering     Hybrid Journal   (Followers: 8)
Chemical and Process Engineering     Open Access   (Followers: 3)
Chemical and Process Engineering Research     Open Access   (Followers: 5)
Chemical Communications     Full-text available via subscription   (Followers: 29)
Chemical Engineering & Technology     Hybrid Journal   (Followers: 24)
Chemical Engineering and Processing: Process Intensification     Hybrid Journal   (Followers: 10)
Chemical Engineering and Science     Open Access   (Followers: 2)
Chemical Engineering Communications     Hybrid Journal   (Followers: 10)
Chemical Engineering Journal     Hybrid Journal   (Followers: 20)
Chemical Engineering Research and Design     Hybrid Journal   (Followers: 16)
Chemical Engineering Science     Hybrid Journal   (Followers: 11)
Chemical Geology     Hybrid Journal   (Followers: 9)
Chemical Papers     Hybrid Journal   (Followers: 3)
Chemical Product and Process Modeling     Full-text available via subscription   (Followers: 3)
Chemical Reviews     Full-text available via subscription   (Followers: 310)
Chemical Society Reviews     Full-text available via subscription   (Followers: 30)
Chemical Technology     Open Access   (Followers: 5)
ChemInform     Hybrid Journal   (Followers: 3)
Chemistry & Industry     Hybrid Journal   (Followers: 2)
Chemistry Central Journal     Open Access   (Followers: 5)
Chemistry of Materials     Full-text available via subscription   (Followers: 209)
Chemometrics and Intelligent Laboratory Systems     Hybrid Journal   (Followers: 6)
ChemSusChem     Hybrid Journal   (Followers: 7)
Chinese Chemical Letters     Full-text available via subscription   (Followers: 1)
Chinese Journal of Chemical Engineering     Full-text available via subscription   (Followers: 3)
Chinese Journal of Chemical Physics     Hybrid Journal   (Followers: 1)
Coke and Chemistry     Hybrid Journal  
Coloration Technology     Hybrid Journal   (Followers: 1)
Computational Biology and Chemistry     Hybrid Journal   (Followers: 8)
Computer Aided Chemical Engineering     Full-text available via subscription   (Followers: 2)
Computers & Chemical Engineering     Hybrid Journal   (Followers: 7)
Corrosion Reviews     Full-text available via subscription   (Followers: 4)
Crystal Research and Technology     Hybrid Journal   (Followers: 2)
Current Opinion in Chemical Engineering     Open Access   (Followers: 3)
Education for Chemical Engineers     Hybrid Journal   (Followers: 4)
Ekologia : The Journal of Institute of Landscape Ecology of Slovak Academy of Sciences     Open Access  
Eksergi     Open Access  
Emerging Trends in Chemical Engineering     Full-text available via subscription  
European Polymer Journal     Hybrid Journal   (Followers: 41)
Fibers and Polymers     Full-text available via subscription   (Followers: 3)
Focusing on Modern Food Industry     Open Access   (Followers: 3)
Frontiers of Chemical Science and Engineering     Hybrid Journal   (Followers: 1)
Geochemistry International     Hybrid Journal  
Handbook of Powder Technology     Full-text available via subscription   (Followers: 2)
High Performance Polymers     Hybrid Journal  
Indian Chemical Engineer     Hybrid Journal   (Followers: 3)
Indian Journal of Chemical Technology (IJCT)     Open Access   (Followers: 12)
Industrial & Engineering Chemistry     Full-text available via subscription   (Followers: 9)
Industrial & Engineering Chemistry Research     Full-text available via subscription   (Followers: 18)
Industrial Chemistry Library     Full-text available via subscription   (Followers: 4)
International Journal of Chemical and Petroleum Sciences     Open Access   (Followers: 2)
International Journal of Chemical Engineering     Open Access   (Followers: 6)
International Journal of Chemical Reactor Engineering     Full-text available via subscription   (Followers: 3)
International Journal of Chemical Technology     Open Access   (Followers: 4)
International Journal of Chemoinformatics and Chemical Engineering     Full-text available via subscription   (Followers: 2)
International Journal of Food Science     Open Access   (Followers: 2)
International Journal of Industrial Chemistry     Open Access  
International Journal of Polymeric Materials     Hybrid Journal   (Followers: 3)
International Journal of Science and Engineering     Open Access   (Followers: 7)
International Journal of Waste Resources     Open Access   (Followers: 5)
ISRN Chemical Engineering     Open Access   (Followers: 4)
ISRN Polymer Science     Open Access   (Followers: 11)
Journal of Applied Crystallography     Hybrid Journal   (Followers: 4)
Journal of Applied Electrochemistry     Hybrid Journal   (Followers: 8)
Journal of Applied Polymer Science     Hybrid Journal   (Followers: 194)
Journal of Biomaterials Science, Polymer Edition     Hybrid Journal   (Followers: 8)
Journal of Chemical & Engineering Data     Full-text available via subscription   (Followers: 6)
Journal of Chemical Ecology     Hybrid Journal   (Followers: 2)
Journal of Chemical Engineering     Open Access   (Followers: 4)
Journal of Chemical Engineering and Materials Science     Open Access  
Journal of Chemical Science and Technology     Open Access   (Followers: 2)
Journal of Chemical Sciences     Partially Free   (Followers: 15)
Journal of Chemical Technology & Biotechnology     Hybrid Journal   (Followers: 2)
Journal of Chemical Theory and Computation     Full-text available via subscription   (Followers: 9)
Journal of Coatings     Open Access   (Followers: 3)
Journal of Crystallization Process and Technology     Open Access   (Followers: 5)

        1 2     

Journal Cover Geochemistry International
   Follow    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 1556-1968 - ISSN (Online) 0016-7029
     Published by Springer-Verlag Homepage  [2210 journals]   [SJR: 0.401]   [H-I: 13]
  • Residence sites and origin of noble gases in minerals as exemplified by
           ilmenite from the alkaline granites of the Kola Peninsula
    • Abstract: Abstract Thermal analysis of helium release from ilmenite of alkaline granites (Ponoy Massif, Kola Peninsula) and extraction of gases by crushing, melting and vacuum stepwise heating of sample revealed that this mineral contains noble gases in several different residence sites (rs). Radiogenic 40Ar* and He are released within the temperature range of 400–600°C. However, in spite of the similar extraction temperatures, these gases occupy different rs: trapped excess 40Ar* is localized in relatively large inclusions (> 10 μm) and was almost completely released during crushing (more than 80%, first rs), whereas He is localized in “healed” α-tracks and was released during sample heating (second rs). The third rs is almost completely occupied by radiogenic He released at temperature around 1100°C; this temperature fraction has 4He/40Ar* = 830, whereas this ratio in whole sample is 10. Helium with the highest 3He/4He = 1.1 × 10−6, indicating a contribution of mantle helium, is released from the fourth rs. Observed distribution of helium and argon isotopes in ilmenite is consistent with geological data on the evolution of the Ponoy Massif. Quartz-feldspathic vein, from which ilmenite was collected, was formed by crystallization of residual alkali granitic melts; the melts contained mantle He, which finally was incorporated in primary inclusions (fourth rs). After formation, the massif rocks accumulated radiogenic 40Ar*, but lost more mobile radiogenic He. During Paleoproterozoic metamorphism of the Ponoy Massif, radiogenic 40Ar* was released from K-bearing minerals of granites and impregnated “potassium-poor” ilmenite (first rs). Then, trapped 40Ar* was preserved in mineral inclusions, while helium produced “in situ” during radioactive decay of U and Th mainly migrated from the mineral. At present, ilmenite is characterized by significant excess 40Ar*, and, simultaneously, by 4He deficit (second and third rs). Neither K-Ar, nor U-Th-He isotope systems of the mineral can be used for dating.
      PubDate: 2014-12-01
       
  • Geochemical patterns of the Buyukkizilcik (Kahramanmaras) fluorite
           deposits
    • Abstract: Abstract The aim of this study is to demonstrate the origin of fluorites that are located near the Dinari area in Buyukkizilcik (Kahramanmaras). Buyukkizilcik fluorites are spatially associated with the altered portion of the Permian Yoncayolu Formation and are also commonly hosted by the syenitic intrusions. Geochemical properties of the Buyukkizilcik fluorites have been investigated by characterizing their rare earth element (REE) compositions. The fluorite samples are poor in terms of their REE contents with REE abundances of the analyzed samples ranging between 0.45 and 11.99 ppm, whereas REE concentrations of the associated host-rocks vary between 0.01 and 17.30 ppm. When plotted on a Tb/La vs. Tb/Ca diagram, the fluorites lie within the field of hydrothermal stage indicating that they are likely formed by the contribution from hydrothermal fluids. The relative depletion of high-field strength elements (HFSE) and REE in the fluorites relative to their host-rocks indicates the influence of hydrothermal fluids on these elements. The negative anomalies observed in Eu and positive anomalies observed in Ce indicate low temperature (T) and low fO2 conditions during formation. In addition, Sc/Eu vs Sr, (La/Yb)n-(Eu/Eup)n, Sc-SREE, (Tb/Yb)n-(La/Yb)n, Tb/Ca-Tb/La diagrams also provide important information regarding the origin of the Buyukkizilcik fluorites. As a result, the geochemical data and related plots presented in this study imply that the fluorites were formed from hydrothermal fluids within an alteration zone of an intrusion.
      PubDate: 2014-12-01
       
  • Geochemical features of the quaternary lamproitic lavas of Gaussberg
           Volcano, East Antarctica: Result of the impact of the Kerguelen plume
    • Abstract: Abstract Petrological-geochemical data were obtained on the lamproites of the Gaussberg Volcano located at the eastern Antarctic coast and compared with data on the magmatic rocks developed in the East Antarctica and Indian Ocean in relation with the Kerguelen plume. It was shown that the lamproites were derived from the ancient Gondwana lithosphere repeatedly modified at the early stages of its evolution, including significant enrichment in volatiles, lithophile elements, and radiogenic Sr and Pb isotopes. The Gaussberg Volcano located on the eastern Antarctic continental margin falls in the distribution field of the Kerguelen plume, which formed 130 Ma within the incipient Indian Ocean and is continuing to operate at present, forming volcanic rocks of Heard Island in the last ka. Manifestations of alkaline magmatism at the Antarctic margin around 56 ka (Mt. Gaussberg) indicate a sublithospheric spreading of mantle plume in the southwestern direction.
      PubDate: 2014-12-01
       
  • 238 U/ 235 U isotope ratio variations in minerals from hydrothermal
           uranium deposits
    • Abstract: Abstract The 238U/235U ratio was precisely measured in uranium minerals from 11 hydrothermal deposits of different geologic settings and ages situated in ore regions of Asia, Europe, Africa, and North America by MC-ICP-MS using a 233U-236U double spike. The spike was calibrated in reference to the CRM-112A standard with 238U/235U = 137.837 ± 0.015 (Richter et al, 2010). The long-term reproducibility of 238U/235U measurement was estimated as ±0.07‰ by the analysis of monitor samples and the IRMM-3184 standard. The analyses were performed using 0.02–0.04-mg microsamples of uraninite, pitchblende, and coffinite, which were locally extracted from polished sections under an optical microscope. The 238U/235U values obtained for 50 samples of U-bearing minerals range from 137.703 to 137.821, with a 0.86‰ difference and a mean 238U/235U value of 137.773 ± 0.056 (±2SD). The range of 238U/235U variations in seven deposits with uraninite is 0.41‰, which is twice as low as for the deposits with pitchblende-dominated ores. Our study provided the first results for 238U/235U variations in minerals from individual deposits. The largest variations were found in the Oktyabr’skii (Eastern Transbaikalia), Schlema-Alberoda (Erzgebirge), and Shea Creek (Athabasca basin) deposits: 0.70, 0.33, and 0.59‰, respectively. Uranium from the early growth zones of 4–5 mm thick pitchblende spherulitic crusts is isotopically heavier (by 0.22–0.45‰) than uranium from the latest growth zones. A similar isotopic shift in 238U/235U in terms of magnitude (0.31‰) and sense was observed between pitchblende and coffinite overgrowths. The uranium isotopic composition of late pitchblende generations, the products of dissolution and reprecipitation of early phases, is 0.46‰ lighter than that of early pitchblende phases. The character of uranium isotope distribution in pitchblende aggregates is consistent with nuclear-volume-dependent isotope fractionation accompanying U(VI) reduction to U(IV) (Bigeleisen, 1996; Schauble, 2007; Stirling et al., 2007), which causes an enrichment of the U(IV)-bearing solid phase in the heavy isotope 238U. The range of 238U/235U ratios for 11 hydrothermal (high-temperature) deposits (137.703–137.821) lies well within the broader (two-fold) range of values determined for the low-temperature deposits Dybryn in Transbaikalia (Golubev et al., 2013) and Pepegoona in South Australia (Murphy et al., 2014). This can be explained by the fact that the uranium isotopic fractionation associating with U(VI) → U(IV) reduction is accompanied by isotope shifts owing to the long-term interaction of groundwater with early phases within sandstone-type deposits. At the same time, owing to the higher temperatures (by 100–300°C) of formation of hydrothermal deposits compared with sandstone-type deposits, nuclear-volume-dependent uranium isotope fractionation decreases by more than a factor of 2 (Bopp et al., 2009).
      PubDate: 2014-12-01
       
  • Microheterogeneity of crystal growth zones as a result of REE
           fractionation
    • Abstract: Abstract Structural features of rhythmically zoned florencite and xenotime crystals from quartz veins of the Au-REE occurrences of the Near-Polar Urals are considered. The crystals were studied in the growth zones 0.01–0.15 mm wide. Rhythms consist of small structural elements: oriented intergrowths of several mineral species, layered-block distribution of Sr and Ca, syntaxic intergrowths of minerals of the same structural type, cocrystallization caverns, and late dissolution cavities with inclusions of argentite and pitchblende. The growth zones of crystals show successive change in lanthanides: from light to heavy REEs in florencite, and, vice versa, in xenotime, which is explained by the Ce and Y activity. The mechanism of element fractionation in the crystals is of dual nature. The rare-earth intergrowths contain four lanthanide groups: (La-Ce-Pr), (Nd-Sm-Eu-Gd), (Gd-Tb-Dy), (Ho-Er-Tm-Yb-Lu). This is caused by complexing ability of the elements, which is expressed in the tetrad effect of REE fractionation. Crystals, in turn, separate isomorphic complexes according to the properties of its facets and concentrations of elements in solutions. The structures of crystals and their growth elements are considered from the crystallochemical viewpoint.
      PubDate: 2014-12-01
       
  • Is the Fischer-Tropsch process possible in a geologic medium?
    • PubDate: 2014-12-01
       
  • Behavior of lanthanides during the formation of the Iul’tin deposit,
           Chukchi Peninsula
    • PubDate: 2014-12-01
       
  • Interaction of dissolved organic matter with Hg(II) along salinity
           gradient in Boston Lake
    • Abstract: Abstract Mercury pollution has become one of the serious ecological and health problems in developing countries. In aquatic environments, widespread dissolved organic matter (DOM) affects the physical transfer, chemical transformation and bioavailability of heavy metal ions. In the arid inland lakes, water salinity has been increasing due to close hydrological system and much higher vaporization than precipitation, and thus there are usually salinity gradients in these inland lakes. The change of salinity may exert influences on complexation of DOM with heavy metals. However, response of the metal complexation of DOM to the salinity is still unclear. In this study, three-dimensional molecule fluorescence spectroscopy (3D-EEM) was used to examine the interaction of Hg(II) and DOM in sediment along a salinity gradient of the Bosten Lake, the biggest inland freshwater lake in China. Three fluorescence peaks were identified in the EEM fluorescence spectra of all DOM samples. All the three fluorescence peaks could be quenched by Hg(II), indicating the formation of stable nonluminous DOM-Hg complexes. The conditional stability constant and binding constant for DOM-Hg(II) were 3.82–4.34 and 3.76–5.54, respectively. Conditional stable constants and binding constants for the system of Hg(II) and protein-like substances were higher than those for the humic substances-Hg(II) system. The ligand ratio of fluorophore to Hg(II) correlated well with the salinity. The strong complexation of Hg(II) and DOM and its responses to salinity change may significantly influence transport, transformation and ecological risk of Hg in Bosten Lake.
      PubDate: 2014-12-01
       
  • Partition geochemistry of hydrothermal precipitates from submarine
           hydrothermal fields in the Hellenic Volcanic Island Arc
    • Abstract: Abstract The geochemical study of 5 sediment cores obtained from different shallow hydrothermal fields along the volcanic arc (Methana, Milos, Kos and Yali), revealed that the degree of rock hydrothermal alteration from one area to another is different and is influenced by the physical and geochemical properties of the hydrothermal venting fluids and the type of the rocks in the substrate. The submarine hydrothermal fields in the central Aegean Sea are linked with the Hellenic Volcanic Arc and imprint their hydrothermal influence on the local marine sediments. Hydrothermal venting fluids differ in pH, temperature, gas and metallic element content, intensity of gas and water flux, while rock substrate is variable in terms of thickness and chemistry of the marine sediments and the mineral deposits. The analytical results showed that the lowest values of Fe are observed in Palaeochori Bay (0.72%) and the highest values are found in Bros Thermi (2.72%). The highest Mn concentrations are found in Bros Thermi (407 ppm) and the lowest are found in Yali (29 ppm). Cu and Pb highest concentrations are found in Bros Thermi (21 ppm) and Thiafi Bay (16 ppm), and the lowest in Yali (1 ppm). Zn highest values are found in Bros Thermi (56 ppm) and the lowest values in Kephalos Bay (10 ppm). Finally, the Ca and Mg-richest layers are observed in Kephalos 7.5 and 0.98% respectively and the lowest are observed in Milos (0.01% for Ca) and Yali (0.12% for Mg). The hydrothermal activity presented variations with geological time and hydrothermal suspended particulate matter coming out from the vent outlets also influence the sediment geochemistry. As an example in Methana, high concentrations of Cu and Zn in SPM result in high levels of Cu and Zn in the sediments.
      PubDate: 2014-11-01
       
  • Identification of anthropogenic radionuclides in the Song Hong (Red) and
           Song Da (Black) river basins of Vietnam
    • Abstract: Abstract The concentration and distribution of U were measured in zircon samples separated from the streambed sediments collected at different sites along the rivers of northern Vietnam using semiconductor alpha spectrometry and alpha- and fission-track autoradiography. Based on the absolute U content and distribution, we distinguished two groups of zircon grains of different origin. Group 1 zircons have relatively low and uniform U contents ranging from 280 to 440 μg/g. Group 2 zircons are characterized by heterogeneous U distribution and U contents ranging from 490 to 2040μg/g. The determination of absolute alpha activity values and alpha spectrometric characteristics for a number of group 2 zircon grains indicated the presence of relatively short-lived alpha-emitters. These radionuclides are probably 210Po, 232U, 236Pu, 241Am, and 243Am, and all of them can originate exclusively from anthropogenic sources. A comparison of the observed alpha activity values for group 2 zircons with those of group 1 zircons and zircons separated from the suspended colloids in river water samples provided conclusive evidence for traces of anthropogenic radioactive contamination in the Lao Cai, Yen Bai, Tuyen Quang, Thac Ba, Viet Tri, and Hanoi streams flowing in the Song Hong (Red) and Song Da (Black) river basins of northern Vietnam and sourced in the southern regions of the neighboring state.
      PubDate: 2014-11-01
       
  • Physicochemical parameters of the material of mantle plumes: Evidence from
           the thermodynamic analysis of mineral inclusions in sublithospheric
           diamond
    • Abstract: Abstract Thermodynamic analysis of equilibria involving minerals of the lower mantle of pyrolite composition and crystalline carbon-bearing compounds indicates that the range of oxygen fugacity values at which diamond can be formed is separated from the region in which Fe-rich metallic alloy is generated by a field in which Fe carbides are stable. This implies that diamond can be formed in the lower mantle under more oxidizing conditions than those thought to be dominant in this geosphere. The absence of a metallic phase from the lower-mantle diamond-bearing mineral assemblage is consistent with the high (approximately 1%) Ni concentration in the ferropericlase found as inclusions in diamonds (Fe-rich metallic alloy is able to intensely extract Ni). An elevated redox potential also follows from the occurrence of carbonate phases found among mineral inclusions in lower-mantle diamonds. The main reason for a local increase in oxygen fugacity in the lower mantle may be shifts of redox equilibria toward a decrease in the amount, and then the disappearance of the Fe-Ni alloy with increasing temperature. An important role in the formation of diamond may be played by the generation of carbonate-phosphate and silicate melts in high-temperature zones and the migration of these melts and their interaction with wall rocks.
      PubDate: 2014-11-01
       
  • Pelitic rocks from the molasse formation of the Southern Ural segment of
           the Uralian foredeep: Lithogeochemistry, provenance composition, and
           paleotectonic reconstructions
    • Abstract: Abstract In this paper, we consider the lithogeochemical characteristics of pelitic rocks from the molasses (Late Permian) of the Southern Ural segment of the Uralian foredeep. The examination of mudstones showed that they contain high and variable amounts of secondary carbonate minerals and, consequently, high and variable CO2, which complicates the use of traditional lithochemical diagrams for their classification and genetic reconstructions. On the other hand, the lithogeochemical characteristics of the pelites (as well as psammites) provided evidence on the compositions of provenances in paleocatchments. High Cr and Ni contents indicate the presence of ultrabasic rocks in the provenances, and the distribution of Cr/Ni values suggests insignificant chemical homogenization of aluminosilicate fine-grained clastic materials and, consequently, short transport distances. The dominant first-cycle nature of the clay rocks is indicated by the relations of major oxides and various lithochemical indexes. The heterogeneous and complex composition of the end-Permian provenance is supported by the covariation diagrams of indicator trace element ratios.
      PubDate: 2014-11-01
       
  • Trace element distribution in mineral inclusions in zoned garnets from
           eclogites of the Atbashi Range (South Tianshan)
    • Abstract: Abstract Ion microprobe data for minerals from the eclogites of the Atbashi Range (South Tianshan) constrain the distribution of trace (Rb, Sr, Ba, Cr, V, Zr, Hf, Nb, Ta, U, Th, and Y) and rare-earth elements (REE) in zoned garnets and mineral inclusions in them. This study showed that garnets from the Atbashi eclogites are the main hosts for heavy REE; epidotes are important hosts for REE, Y, Sr, Th, and U; and omphacites are depleted in almost all trace elements compared with the bulk-rock compositions. Garnet, as well as epidote and omphacite inclusions exhibit systematic rimward depletion in a number of trace elements, which is related to the depletion of the rock matrix in these elements during crystallization. Deviations from this trend, including the enrichment of garnet rims in HREE and strong variations in the REE contents of garnets and mineral inclusions, can be explained by metamorphic reactions involving the destabilization of REE-bearing minerals. Our data suggest that the mobility of trace elements under eclogites-facies conditions is mainly controlled by the stability of certain minerals.
      PubDate: 2014-11-01
       
  • Erratum to: “Stability conditions of polycyclic aromatic
           hydrocarbons at high pressures and temperatures”
    • PubDate: 2014-11-01
       
  • Elucidation of the hierarchy of processes transforming the pore space of
           water-hosting rocks based on thermodynamic simulation results
    • Abstract: Abstract A series of thermodynamic simulations was carried out at varied physicochemical parameters within the framework of a single model experiment in a marginal part of an artesian basin. The transformation of the pore space is proved to be more significantly dependent on temperature than on the initial porosity of the rocks. The extent to which the water-rock system is open (or closed) plays a subordinate role in trans-forming the porosity of the rocks via indirectly controlling the leaching conditions of carbonate rocks. The filtration rate only insignificantly affects the saturation of the groundwaters at certain sites within the aquifer at given P-T parameters. In analyzing this criterion, the mineralogical composition of the host rocks plays the leading role.
      PubDate: 2014-11-01
       
  • Geochemistry of the Osnitsk-Mikashevichy volcanoplutonic complex of the
           Ukrainian shield
    • Abstract: Abstract This paper addresses the geochemistry of intrusive (Osinitsk complex) and volcanic (Klesov Group) rocks of the Osnitsk-Mikashevichy volcanoplutonic belt (OMVPB) of the Ukrainian shield, which is an active continental margin existing approximately 1980–2000 Ma ago. The Osnitsk complex comprises a wide range of rocks, from ultrabasics to granitoids, and the Klesov Group is dominated by extrusive rocks of basaltic and rhyolitic compositions metamorphosed under epidote-amphibolite facies conditions. The Sr-Nd-Hf isotopic systematics (ɛSr1990 from −4 to +10, ɛNd1990 from −0.6 to +2.3, and ɛHf1990 from 0.1 to 1.4) indicates a juvenile source for the OMVPB rocks. Geochemical data suggest independent origin of the rocks of gabbroid (SiO2 < 60 wt %) and granitoid (SiO2 > 60 wt %) series. The gabbroids are subdivided into pre- and post-granite groups on the basis of the higher contents of incompatible trace elements and lower contents of compatible elements in the post-granite rocks. The geochemical characteristics of the two groups of basic rocks indicate their formation in a convergent tectonic setting. The origin of the granitoid melts is attributed to the low-degree (eutectoid) melting of basic rocks at relatively low temperatures.
      PubDate: 2014-11-01
       
  • Gold sulfoarsenide complexes in ore-forming hydrothermal solutions
           (thermodynamic modeling)
    • PubDate: 2014-10-01
       
  • Fourteenth International Symposium on Water-Rock Interaction, Avignon,
           France, June 9–14, 2013
    • PubDate: 2014-10-01
       
  • On the preservation of Xe of the isotopically normal component of noble
           gases in meteoritic nanodiamonds and        class="a-plus-plus">4He in lunar soil according
           to the data of gas desorption during stepped pyrolysis
    • Abstract: Abstract The release kinetics of Xe of the isotopically normal component of noble gases (P3 component) from the coarse-grained fraction of nanodiamonds from the Orgueil (CI) meteorite and the kinetics of 4He release from lunar soil were studied by means of a numerical simulation. It is demonstrated that the release of these gases as a peak with a single pronounced maximum may not correspond to the diffusion model with a single activation energy and can in fact be controlled by a spectrum of activation energies with a number of peaks a number of peaks remaining unresolved at stepped pyrolysis. In particular, the amount of Xe-P3 preserved in nanodiamonds during thermal metamorphism of the Orgueil meteorite calculated using parameters of the diffusion process (activation energy and frequency factor) that were determined in the model with a single activation energy indicates that practically all Xe should be lost during a very short time. These losses are inconsistent with both the duration of thermal metamorphism of the meteorite parent bodies and the Xe-P3 concentrations measured in these meteorites. A much higher preservation of Xe-P3 during thermal metamorphism lasting for hundreds of years follows from calculations based on diffusion with a spectrum of activation energiesa for Xe release. The results of isothermal pyrolysis of a nanodiamonds fraction from Orgueil confirms a presence of several activation energies for Xe-P3 release from the nanodiamonds. The application of the diffusion model with a spectrum of activation energies to He release from lunar soil samples also shows that He can be retained in these samples at 20°C during a much longer time than it follows from the model with a single activation energy (Anufriev, 2010).
      PubDate: 2014-10-01
       
  • Effect of groundwater runoff on the chemical composition of the
           delta-front water of the Selenga River, Lake Baika
    • PubDate: 2014-10-01
       
 
 
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