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1.
E. N. Gramenitskii A. R. Kotel’nikov T. I. Shchekina O. V. Yakubovich V. N. Devyatova E. S. Zubkov N. I. Suk M. F. Vigasina Z. A. Kotel’nikova 《Geochemistry International》2018,56(6):521-534
Fluoro-sodalite was synthesized for the first time at temperatures of 400–800°C and H2O pressures of 1–2 kbar in the Si–Al–Na–H–O–F system. X-ray diffraction and infrared spectroscopic investigations showed that fluorine is incorporated in the sodalite structure as anionic octahedral groups, [AlF6]3–, the number of which can vary from 0 to 1. Correspondingly, the end-members of the F-sodalite series are Na7(H2O)8[Si5Al7O24] and Na8(AlF6)(H2O)4[Si7Al5O24]. Depending on the composition of the system, F-sodalite associates at 500–650°C with nepheline, albite, cryolite, and villiaumite, which are joined by analcime below 500°C and aluminosilicate melt above 650°C. Fluorine-bearing sulfate–chlorine-sodalite was found for the first time in a pegmatite sample from the Lovozero massif. The highest fraction of the fluorine end-member in natural sodalite is 0.2. The incorporation of F into the sodalite structure requires much more energy compared with Cl– and SO 4 2- , because it is accompanied by a structural rearrangement and a transition from tetrahedral Al to octahedral Al. 相似文献
2.
V. S. Zubkov 《Geochemistry International》2009,47(8):741-757
Literature data suggest that concentrated naphthides (CN)—bitumen and oil—can occur in intrusive and volcanic rocks of various
silicity and alkalinity whose age ranges from the Proterozoic to Recent. The qualitative composition of heavy (high-molecular)
hydrocarbons (HHC) in CN is the same in various rocks: heavy alkanes, polycyclic aromatic hydrocarbons (PAH), oxygen-bearing
derivatives of hydrocarbons, etc. The presence of CN in rock-forming minerals in magmatic rocks and pegmatites confirms that
CN condensed during the epimagmatic stage, and the molecular mass of the CN, for example, in the Khibina alkaline massif decreased
with decreasing temperature simultaneously with the evolution of its mineral assemblages. The synthesis of CN continues during
the hydrothermal stage, but high-temperature associations of HHC gave way during this stage to low-temperature ones. During
all evolutionary stages of magmatic and related processes, the contents of CN are correlated with those of trace elements,
which likely occur as organoelement compounds (OEC). Hypotheses of endogenic and exogenic genesis of CN in magmatic rocks
are discussed. The endogenic hypotheses include HHC synthesis from inorganic gases and light hydrocarbons (HC) on catalytic
minerals. The fact that HHC and CN occur in mantle xenoliths and high-pressure minerals and the results of experimental and
thermodynamic modeling are discussed as supporting the hypothesis of the mantle genesis of CN in magmatic rocks. The metastable
ascent of gaseous HHC, the low oxygen fugacity, and the high alkalinity of the melts could be favorable for the partial preservation
of HHC in these rocks at crustal depth levels. Endogenic CN can serve as a nutrient medium for microorganisms in the upper
lithosphere. Exogenic hypotheses for the genesis of HHC in magmatic rocks assume that the melts should have assimilated sedimentary
rocks rich in organic matter and that biogenic oil could be transported from sedimentary reservoirs to magmatic rocks. An
important role in determining the genesis of CN in magmatic rocks is played by endogenic and biogenic markers. 相似文献
3.
Amy R. Kirkham Ludwig E. Jardillier Ross HollandMikhail V. Zubkov Dave J. Scanlan 《Deep Sea Research Part I: Oceanographic Research Papers》2011,58(7):733-744
Photosynthetic picoeukaryotes (PPEs) of a size <3 ??m can contribute significantly to primary production. Here, PPE community structure was analysed along an extended Ellett Line transect, an area in the North Atlantic well studied by physical oceanographers but largely neglected in the field of microalgal ecology. Distribution patterns of specific PPE classes were determined using dot-blot hybridization analysis, while the taxonomic composition of specific PPE classes was revealed by phylogenetic analysis of plastid 16S rRNA gene sequences. In addition, we performed fluorescent in situ hybridization (FISH) analysis of seawater samples collected along the transect to provide a PCR-independent survey of class level PPE distribution patterns. We found the PPE community was dominated by members of the Prymnesiophyceae, Prasinophyceae and Mamiellophyceae. Interestingly, phylogenetic analysis revealed several novel Prymnesiophyceae and Prasinophyceae phylotypes (with only 85-96% identity to neighbouring sequences) within lineages for which cultured counterparts are unknown. 相似文献
4.
A. M. Nikanorov O. B. Bartsev D. N. Gar’kusha E. A. Zubkov L. I. Minina 《Water Resources》2017,44(7):952-962
Underflooding of different extent was recorded in 133 populated localities in southern Rostov oblast, among which 4 such localities are always partly underflooded, and 77 localities suffer underflooding during spring floods and freshets. Minimal estimates show that the area of the territories underflooded every year and only in wet years is 282 km2 or 19% of the total built-up area in the southern Rostov oblast. Technogenic factors were found to dominate as the causes of underflooding in the majority of the populated localities. However, natural or slightly disturbed subsoil water regime is typical of the built-up territories in the southern Rostov oblast, where it implies annual periodicity of level variations with a peak in spring and a minimum in autumn. 相似文献
5.
The paper presents several examples of metalliferous naphtide mineralization hosted in sedimentary and magmatic rocks and
discusses different models of their origin. Geological, geochemical, experimental, and thermodynamic data were used to support
a hypothesis assuming that metalliferous naphtide deposits were formed during cold and hot (with melt generation) mantle degassing
with subsequent condensation of heavy hydrocarbons and organometallic compounds (OMC) in fault zones. Important criteria for
discrimination between metalliferous naphtide mineralization of different origin include endo- and biomarkers, Nd and Sr isotopic
data, and chondrite-normalized REE distribution patterns. The formation of endogenic metalliferous naphtide deposits does
not rule out the possible assimilation of organic components from the host rock. Juvenile water and inorganic gases were found
in the hydrothermal solutions contributing to the formation of these deposits. 相似文献
6.
S. P. Pozdniakov V. A. Bakshevskaya I. V. Krohicheva V. V. Danilov A. A. Zubkov 《Moscow University Geology Bulletin》2012,67(1):43-51
Development of heterogeneity model of layered sandy-clay formation and impact of this model on transport is considered. The
lithological data of more than 250 wells that captured 300 meters formation at the investigated area of 40 km2 are used for model of heterogeneity construction. Two models of heterogeneity were developed with using these well data:
TP/MC model based on 3D Markov chain simulation for four hydrofacies and 2D kriging interpolation of thicknesses of elementary
lithological layers. Simulation of conservative transport by particle tracking algorithm shows that horizontal transport along
layers is similar for both models. The main difference is in vertical transport cross formation bedding. The kriging interpolation
model gives more conservative results than TP/MC model due to larger characteristic horizontal length of layers in the kriging
model. As the result vertical effective hydraulic conductivity of formation is in two times larger and the first particle
arriving time is in four times faster in TP/MC model. 相似文献
7.
As a continuation of previous studies of 3H, δ2H, δ18O, Ar, 40Ar/36Ar, and 234U/238U isotope systems, data of uranium-helium dating of groundwater at the radioactive waste repository of Siberian Chemical Works are quantitatively interpreted. The interpretation is based on analytical models taking into account the inflow of deep-earth helium and the diffusion-advection exchange between layers. Estimated flow velocities in reservoir beds and buffer horizons are in agreement with previous hydrodynamic estimates. The obtained velocities of horizontal mass transfer were used to evaluate the age of groundwater in sampling points. Water age varies from 7 to 14 (with a mean of ～9) in the lower (II and III) aquifers, into which the radioactive wastes are pumped, from 2 to 4 in buffer horizon IV, and from 1 to 2 thousand years in the upper V horizon. 相似文献
8.
I. V. Tokarev A. A. Zubkov V. G. Rumynin S. P. Pozdnyakov V. A. Polyakov V. Yu. Kuznetsov 《Water Resources》2009,36(2):206-213
Isotopic characteristics (δ2H, δ18O, 234U/238U, Ar, 3H) of natural and technogenically affected waters were determined in the area around the burying grounds of the Siberian Chemical Combine with the aim to assess the circulation conditions of natural waters and the safety of radioactive waste disposal in reservoir beds. 相似文献
9.
Polly G. Hill Isabelle Mary Duncan A. Purdie Mikhail V. Zubkov 《Progress in Oceanography》2011,91(4):437-446
The Earth’s most extensive biomes – the oceanic subtropical gyres – are considered to be expanding with current surface ocean warming. Although it is well established that microbial communities control gyre biogeochemistry, comparisons of their metabolic activities between gyres are limited. In order to estimate metabolic activities including production of microbial communities, the uptake rates of amino acids leucine, methionine and tyrosine at ambient concentrations were estimated in surface waters of the Atlantic Ocean using radioisotopically labelled tracers. Data were acquired during six research cruises covering main oceanic provinces herein termed: North and South Atlantic Gyres, Bermuda Atlantic Time-series Study site (BATS), Equatorial region, and Mauritanian Upwelling (off Cape Blanc). Data were divided between provinces, the extents of which were identified by ocean colour data, in order to achieve provincial mean uptake rates. Leucine and methionine uptake rates did not differ between sampling periods, and were comparable between the North and South subtropical gyres. Furthermore, variation in uptake rates measured throughout the two oligotrophic gyres, where sampling covered ∼4 × 106 km2, was considerably lower than that measured within the Mauritanian Upwelling and Equatorial regions, and even at the BATS site. Tyrosine was generally the slowest of the amino acids to be taken up, however, it was assimilated faster than methionine within the Mauritanian Upwelling region. Thus, we propose that one value for leucine (12.6 ± 3.2 pmol L−1 h−1) and methionine (10.0 ± 3.3 pmol L−1 h−1) uptake could be applied to the oligotrophic subtropical gyres of the Atlantic Ocean. However, with the significantly lower uptake rates observed at the BATS site, we would not advise extrapolation to the Sargasso Sea. 相似文献
10.
The equilibrium thermodynamic calculations made for C-H and C-H-N-O-S systems show that the mantle might contain a fluid consisting
of heavy (high-molecular) hydrocarbons (HHC) and their derivatives, as well as of inorganic gases (H2O, CO2, N2, NH4, H2S, etc.). In the range of diamond-graphite phase transition, the HHC are decomposed to form methane, its nearest homologues,
and graphite. The geochemical and experimental data by different authors point to possible HHC occurrence in the upper mantle.
These results confirm the concept by Dmitrievskii (2006) that the deep fluids might be lifted to the crustal waveguide to
fill its fractures and cavities. Owing to compaction, the fluids are squeezed from the waveguide and lifted into sedimentary
layers to form the commercial hydrocarbon deposits. Resulting from the “washing“ of sedimentary rocks with the fluids, hydrocarbon
gases and oil of organic origin might be formed. 相似文献