U-Pb age and genesis of granitoids in the southern framing of the Pechenga structure,Baltic Shield     

V. R. Vetrin  O. M. Turkina  N. V. Rodionov 《Doklady Earth Sciences》2008,419(1):298-302

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Disseminated ores of the Darasun gold deposit (Eastern Transbaikalia) and their genesis     

V. Yu. Prokof’ev  N. S. Bortnikov  A. V. Volkov  I. A. Baksheev  L. D. Zorina 《Doklady Earth Sciences》2008,422(1):1025-1027

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Dependence of the water content in channels of the cordierite structure on the composition of its Fe-Mg solid solutions     

T. A. Bul’bak  S. V. Shvedenkova 《Doklady Earth Sciences》2008,419(2):477-480

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The structure of the tectonosphere of the Urals and West Siberian Platform by electromagnetic data     

A. G. D’yakonova  K. S. Ivanov  O. V. Surina  P. F. Astaf’ev  V. S. Vishnev  A. D. Konoplin 《Doklady Earth Sciences》2008,423(2):1479-1482

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The Sunyaev-Zel’dovich effect in elliptical galaxies     

B. V. Komberg  D. I. Nagirner  I. V. Zhuravleva 《Astronomy Reports》2008,52(9):707-713

The history of the discovery of hot gas in galaxies is briefly reviewed, and the main properties of this gas described, emphasizing the need to refine these properties, in particular, the mass of the gas. It is proposed to do this via observations of the Sunyaev-Zel’dovich (SZ) effect due to hot gas in the coronas of elliptical galaxies. The absolute and relative perturbations of the spectrum of the cosmic microwave background (CMB) radiation due to scattering of the CMB photons by electrons with a Maxwellian energy distribution are calculated. The possibility of observing the SZ effect is demonstrated using three elliptical galaxies as examples. The kinematic SZ effect arising due to the peculiar motions and rotations of the galaxies is also accessible to observations. Together with X-ray data, such observations would enable refinement of the properties of gas in galaxies, and also yield additional information about the rotation of galaxies, possible accretion flows in the galactic gas, and hot galactic winds.  相似文献   

Different magneto-rotational supernovae     

G. S. Bisnovatyi-Kogan  S. G. Moiseenko  N. V. Ardelyan 《Astronomy Reports》2008,52(12):997-1008

We present the results of two-dimensional calculations of a magneto-rotational (MR) supernova explosion with a collapsing core for various core masses, rotational angular momenta, and magnetic-field configurations. It is shown that the MR mechanism produces an explosion energy that corresponds to observed values. The form of the explosion depends substantially on the initial configuration of the magnetic field. MR instability develops during the evolution of the magnetic field in an MR supernova explosion, resulting in an exponential increase of all components of the magnetic field, thereby substantially decreasing the time scale of the MR explosion. The energy of the supernova increases with the core’s mass and initial rotational energy.  相似文献   

Elpasolite from hyperalkaline pegmatite of the Khibiny pluton, Kola Peninsula. Symmetry of elpasolite     

I. V. Pekov  N. V. Chukanov  N. N. Kononkova  N. V. Zubkova  M. Kh. Rabadanov  D. Yu. Pushcharovsky 《Geology of Ore Deposits》2008,50(8):749-754

Elpasolite, K₂NaAlF₆, has been found for the first time in a pegmatite related to peralkaline foid syenite at Mt. Koashva, Khibiny alkaline pluton, Kola Peninsula, Russia, as pale pink octahedral crystals up to 2 mm in size within cavities in the natrolite core of pegmatite in association with amicite, sodalite, aegirine, pectolite, catapleiite, sitinakite, lemmleinite-K, and vinogradovite. The chemical composition determined with an electron microprobe is as follows, wt %: 31.53 K; 9.22 Na; 11.20 Al; 47.21 F; total is 99.16. The empirical formula is K_1.96Na_0.98Al_1.01F_6.05. The infrared spectrum is given. The crystal structure has been refined to R = 0.030, space group Fm $ \bar 3 Elpasolite, K₂NaAlF₆, has been found for the first time in a pegmatite related to peralkaline foid syenite at Mt. Koashva, Khibiny alkaline pluton, Kola Peninsula, Russia, as pale pink octahedral crystals up to 2 mm in size within cavities in the natrolite core of pegmatite in association with amicite, sodalite, aegirine, pectolite, catapleiite, sitinakite, lemmleinite-K, and vinogradovite. The chemical composition determined with an electron microprobe is as follows, wt %: 31.53 K; 9.22 Na; 11.20 Al; 47.21 F; total is 99.16. The empirical formula is K_1.96Na_0.98Al_1.01F_6.05. The infrared spectrum is given. The crystal structure has been refined to R = 0.030, space group Fm m, a = 8.092 ?. The result of a special X-ray powder diffraction study confirmed the suggestion made by Morss (1974) that reflections violating space group Fm m in some published X-ray powder patterns of natural elpasolite are Kβ-lines. Original Russian Text ? I.V. Pekov, N.V. Chukanov, N.N. Kononkova, N.V. Zubkova, M.Kh. Rabadanov, D.Yu. Pushcharovsky, 2007, published in Zapiski Rossiiskogo Mineralogicheskogo Obshchestva, 2007, No. 6, pp. 76–84.  相似文献   

Microzoning of agates as a reflection of their formation dynamics     

V. V. Slastnikov  Yu. O. Punin  A. R. Nesterov 《Geology of Ore Deposits》2008,50(8):782-788

Agates are natural hierarchicalal structural assemblies composed largely of silica minerals: chalcedony, quartz, and quartzine. Microstructural heterogeneities, most typical of those of agate-forming minerals, are characterized by variations in periods of helicoidal twisting of chalcedony and by micrometric rhythmic alternation of zones with a low refractive index within the matrix of normal chalcedony, quartz, and quartzine. A study of the degree of crystallization of chalcedony using the Barsanova-Yakovleva method showed that neither helicoidal twisting nor refractive index zoning brought about any significant disturbance in the chalcedony structure. Helicoidal twisting is a result of the stresses caused by substitution of Si⁴⁺ for Al³⁺ asymmetric with respect to chalcedony crystal. It is suggested that layering by the refractive index developed due to accumulation of small portions of gel consisting of high silica polymers at the front of crystal growth.  相似文献   

Scheme of mineral facies of metamorphic rocks     

S. A. Bushmin  V. A. Glebovitsky 《Geology of Ore Deposits》2008,50(8):659-669

The proposed PT grid of mineral facies of metamorphic rocks, which retains the commonly adopted nomenclature (greenschist, epidote-amphibolite, amphibolite, granulite, glaucophane-schist, and eclogite facies), is based on original calculations and the published calculated and experimental data on mineral equilibria. To validate the facies and subfacies PT boundaries, the mineral equilibria in metapelitic and metabasic rocks have been used.  相似文献   

Rare earth elements in tourmaline and chlorite from tin-bearing assemblages: Factors controlling fractionation of REE in hydrothermal systems     

N. S. Bortnikov  N. V. Gorelikova  P. G. Korostelev  V. G. Gonevchuk 《Geology of Ore Deposits》2008,50(6):445-461

The REE distribution in minerals from tin-bearing ore-magmatic systems of the Russian Far East, including the Komsomolsk, Khingan, and Badzhal districts in the Amur region and the Kavalerovo, Lesozavodsk, Voznesenka, Furmanovo, and other districts in Primorsky krai, has been studied. The main attention was focused on tourmaline and chlorite; in addition, associated biotite, feldspar, apatite, fluorite, and carbonates were examined. The major factors affecting the REE distribution in the studied minerals are the temperature, Eh, and pH of the mineral-forming medium; crystal chemistry; partition coefficients of REE between fluid and minerals; and complexation that disturbs the coherent behavior of REE. Fluid evolution at different stages is characterized.  相似文献