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1.
A tachometer for measuring the displacements of the center of gravity of spectral line profiles is developed. The implementation of the device, basically a Fabry-Pérot etalon, is given. The spectral shifts are determined, using the frequency of a laser as reference. 相似文献
2.
V. S. Kulikov Ya. V. Bychkova V. V. Kulikova Yu. A. Kostitsyn O. S. Pokrovsky M. V. Vasil’ev 《Petrology》2008,16(6):531-551
The Ruiga differentiated mafic-ultramafic intrusion in the northwestern part of the Vetreny Belt paleorift was described for the first time based on geological, petrological, geochronological, and geochemical data. The massif (20 km2 in exposed area) is a typical example of shallow-facies peridotite-gabbro-komatiite-basalt associations and consists of three zones up to 810 m in total thickness (from bottom to top): melanogab-bronorite, peridotite, and gabbro. In spite of pervasive greenschist metamorphism, the rocks contain locally preserved primary minerals: olivine (Fo 75–86), bronzite, augite of variable composition, labradorite, and Cr-spinels. A mineral Sm-Nd isochron on olivine melanogabbronorite from the Ruiga Massif defines an age of 2.39 ± 0.05 Ga, while komatiitic basalts of the Vetreny Belt Formation were dated at 2.40–2.41 Ga (Puchtel et al., 1997). The rocks of the Ruiga intrusion and lava flows of Mt. Golets have similar major, rare-earth, and trace element composition, which suggests their derivation from a single deep-seated source. Their parent magma was presumably a high-Mg komatiitic basalt. In transitional crustal chambers, its composition was modified by olivine-controlled fractionation and crustal contamination, with the most contaminated first portions of the ejected melt. In terms of geology and geochemistry, the considered magmatic rocks of the Vetreny Belt are comparable with the Raglan Ni-PGE komatiite gabbro-peridotite complex in Canada (Naldrett, 2003). 相似文献
3.
New results on the pressure–temperature–time evolution, deduced from conventional geothermobarometry and in situ U‐Th‐total Pb dating of monazite, are presented for the Bemarivo Belt in northern Madagascar. The belt is subdivided into a northern part consisting of low‐grade metamorphic epicontinental series and a southern part made up of granulite facies metapelites. The prograde metamorphic stage of the latter unit is preserved by kyanite inclusions in garnet, which is in agreement with results of the garnet (core)‐alumosilicate‐quartz‐plagioclase (inclusions in garnet; GASP) equilibrium. The peak metamorphic stage is characterized by ultrahigh temperatures of ~900–950 °C and pressures of ~9 kbar, deduced from GASP equilibria and feldspar thermometry. In proximity to charnockite bodies, garnet‐sillimanite‐bearing metapelites contain aluminous orthopyroxene (max. 8.0 wt% Al2O3) pointing to even higher temperatures of ~970 °C. Peak metamorphism is followed by near‐isothermal decompression to pressures of 5–7 kbar and subsequent near‐isobaric cooling, which is demonstrated by the extensive late‐stage formation of cordierite around garnet. Internal textures and differences in chemistry of metapelitic monazite point to a polyphasic growth history. Monazite with magmatically zoned cores is rarely preserved, and gives an age of c. 737 ± 19 Ma, interpreted as the maximum age of sedimentation. Two metamorphic stages are dated: M1 monazite cores range from 563 ± 28 Ma to 532 ± 23 Ma, representing the collisional event, and M2 monazite rims (521 ± 25 Ma to 513 ± 14 Ma), interpreted as grown during peak metamorphic temperatures. These are among the youngest ages reported for high‐grade metamorphism in Madagascar, and are supposed to reflect the Pan‐African attachment of the Bemarivo Belt to the Gondwana supercontinent during its final amalgamation stage. In the course of this, the southern Bemarivo Belt was buried to a depth of >25 km. Approximately 25–30 Myr later, the rocks underwent heating, interpreted to be due to magmatic underplating, and uplift. Presumably, the northern part of the belt was also affected by this tectonism, but buried to a lower depth, and therefore metamorphosed to lower grades. 相似文献
4.
Changes in the quantitative and qualitative characteristics of zooplankton in Kondopoga Bay, Lake Onega, under long-term anthropogenic influence are discussed, and the effect of water pollution on changes in the zooplankton community is considered. 相似文献
5.
SW Evans N Cole H Kylin NS Choong Kwet Yive V Tatayah J Merven 《African Journal of Marine Science》2016,38(3):317-327
A survey of seabirds and turtles at St Brandon’s Rock, 400 km north of Mauritius, was undertaken in 2010. We estimated that 1 084 191 seabirds comprising seven breeding species and excluding non-breeders were present at the archipelago and we counted 279 turtle tracks and nesting pits of green turtles Chelonia mydas. Hawksbill turtles Eretmochelys imbricata were also present. Analyses of 30 different islets that make up the atoll showed that the seabird species mostly partitioned their use of islets based on islet size, with four species preferring larger islets and two species preferring smaller islets. Alien species introduced historically are still present and other threats, such as shipwrecks, remain. We propose conservation and other measures that should adequately protect the birds, turtles and coral reef by treating the atoll as a system. 相似文献
6.
N. V. Narizhnaya M. Yu. Khovrichev A. A. Apetyan D. A. Bikulova A. P. Ershova I. A. Balyaev A. M. Kulikova K. I. Os’kina L. A. Maksimova 《Solar System Research》2018,52(4):312-319
We present the results of observations of the Galilean moons of Jupiter carried out at the Normal Astrograph of the Pulkovo Observatory in 2016?2017. We obtained 761 positions of the Galilean moons of Jupiter in the system of the Gaia DR1 catalog (ICRF, J2000.0) and 854 differential coordinates of the satellites relative to each other. The mean errors in the satellites’ normal places and the corresponding root-mean-square deviations are εα = 0.0020′′, εδ = 0.0027′′, σα = 0.0546′′, and σδ = 0.0757′′. The equatorial coordinates of the moons are compared to the motion theories of planets and satellites. On average, the (O–C) residuals in the both coordinates relative to the motion theories are less than 0.031′′. The best agreement with observations is achieved by a combination of the EPM2015 and V. Lainey-V.2.0|V1.1 motion theories, which yields the average (O–C) residuals of approximately 0.02″. Peculiarities in the behavior of the (O–C) residuals and error values in Ganymede have been noticed. 相似文献
7.
Boyarskikh I. G. Agatova A. R. Kulikova A. I. Bakiyanov A. I. Skaptsov M. V. Mazeika J. 《Izvestiya Atmospheric and Oceanic Physics》2018,54(8):805-825
Izvestiya, Atmospheric and Oceanic Physics - Areas with large gradients and anomalous variations in geomagnetic and radiation fields have been revealed and mapped at the northwestern foot of the... 相似文献
8.
9.
A. V. Murav’ev I. A. Kulikova Yu. D. Resnyanskii 《Russian Meteorology and Hydrology》2010,35(2):79-93
The spatial and temporal relationships between sea surface temperature anomalies (SSTA) in the North Atlantic and the large-scale
mid-troposphere circulation features in the Northern Hemisphere during the summer and the winter seasons are investigated.
Results are based on atmospheric circulation indices (CI), introduced by Wallace and Gutzler for physical reasoning the low
frequency atmospheric oscillations. Extreme levels and extreme situations in the mid-troposphere were defined and the SSTA
composite charts were constructed with backward lags from 0 to 3 months. Analysis shows that several CI extreme phases of
different signs are associated with synchronous and asynchronous SSTA composites of statistically separable types, or even
antipodes, which may be interpreted as the intraseasonal influence of the ocean on the large-scale mid-troposphere anomaly
features. Noteworthy is the role of the North Atlantic tropical zone in formation of ridges and blocking situations both in
synchronous and asynchronous aspects. The North Atlantic SSTA relations to the West Atlantic Oscillation are shown to be significantly
weaker that the same to the East Atlantic Oscillation. 相似文献
10.
I. V. Pekov N. V. Chukanov I. M. Kulikova D. I. Belakovsky 《Geology of Ore Deposits》2007,49(7):530-536
Phosphoinnelite, an analogue of innelite with P > S, has been found in a peralkaline pegmatite vein crosscutting calcite carbonatite
at the phlogopite deposit, Kovdor pluton, Kola Peninsula. Cancrinite (partly replaced with thomsonite-Ca), orthoclase, aegirine-augite,
pectolite, magnesioarfvedsonite, golyshevite, and fluorapatite are associated minerals. Phosphoinnelite occurs as lath-shaped
crystals up to 0.2 × 1 × 6 mm in size, which are combined typically in bunch-, sheaf-, and rosettelike segregations. The color
is yellow-brown, with vitreous luster on crystal faces and greasy luster on broken surfaces. The mineral is transparent. The
streak is pale yellowish. Phosphoinnelite is brittle, with perfect cleavage parallel to the {010} and good cleavage parallel
to the {100}; the fracture is stepped. The Mohs hardness is 4.5 to 5. Density is 3.82 g/cm3 (meas.) and 3.92 g/cm3 (calc.). Phosphoinnelite is biaxial (+), α = 1.730, β = 1.745, and γ = 1.764, 2V (meas.) is close to 90°. Optical orientation
is Z^c ∼ 5°. Chemical composition determined by electron microprobe is as follows (wt %): 6.06 Na2O, 0.04 K2O, 0.15 CaO, 0.99 SrO, 41.60 BaO, 0.64 MgO, 1.07 MnO, 1.55 Fe2O3, 0.27 Al2O3, 17.83 SiO2, 16.88 TiO2, 0.74 Nb2O5, 5.93 P2O5, 5.29 SO3, 0.14 F, −O=F2 = −0.06, total is 99.12. The empirical formula calculated on the basis of (Si,Al)4O14 is (Ba3.59Sr0.13K0.01)Σ3.73(Na2.59Mg0.21Ca0.04)Σ3.04(Ti2.80Fe
0.26
3+
Nb0.07)Σ3.13[(Si3.93Al0.07)Σ4O14(P1.11S0.87)Σ1.98O7.96](O2.975F0.10)Σ3.075. The simplified formula is Ba4Na3Ti3Si4O14(PO4,SO4)2(O,F)3. The mineral is triclinic, space group P
or P1. The unit cell dimensions are a = 5.38, b = 7.10, c = 14.76 ?; α = 99.00°, β = 94.94°, γ = 90.14°; and V = 555 ?3, Z = 1. The strongest lines of the X-ray powder pattern [d, ? in (I)(hkl)] are: 14.5(100)(001), 3.455(40)(103), 3.382(35)(0
2), 2.921(35)(005), 2.810(40)(1
4), 2.683(90)(200,
01), 2.133(80)(
2), 2.059(40)(204, 1
3, 221), 1.772(30)(0
1, 1
7, 2
2, 2
3). The infrared spectrum is demonstrated. An admixture of P substituting S has been detected in the innelite samples from
the Inagli pluton (South Yakutia, Russia). An innelite-phosphoinnelite series with a variable S/P ratio has been discovered.
The type material of phosphoinnelite has been deposited at the Fersman Mineralogical Museum, Russian Academy of Sciences,
Moscow.
Original Russian Text ? I.V. Pekov, N.V. Chukanov, I.M. Kulikova, D.I. Belakovsky, 2006, published in Zapiski Rossiiskogo
Mineralogicheskogo Obshchestva, 2006, No. 3, pp. 52–60.
Considered and recommended by the Commission on New Minerals and Mineral Names, Russian Mineralogical Society, May 9, 2005.
Approved by the Commission on New Minerals and Mineral Names, International Mineralogical Association, July 4, 2005 (proposal
2005-022). 相似文献