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1.
The first find of srilankite (very rare Zr and Ti oxide, Ti2ZrO6) in the Urals and the third find in Russia is reported. Srilankite forms very small (0.5–20 μm) inclusions in some rutile grains. These minerals are observed in the rare rock variety, corundum-bearing spinel–saphirine hornblendite forming a block in serpentinized amphibolizied peridotite of the Ilmeny–Vishnevogorsk Complex, near the village of Taiginka, Chelyabinsk oblast. Srilankite has not been observed in such an association yet. The composition of the host rock provides evidence for its deep (the lowermost crust of the Earth) origin. Srilankites of the Urals are distinguished from all others by the high concentrations of UO2, ThO2, HfO2, and Nb2O5, which provides additional evidence for their crustal origin. Srilankite may indicate high-temperature and high-pressure conditions of rock formation.  相似文献   
2.
Gallium-containing chlorite, mica, and magnetite (up to 14, 13, and 5–7 wt % of Ga) along with Ga hydroxides (oxyhydroxides?) were found for the first time in massive sulfide deposit in the Urals. The minerals identified within the cement of chalcopyrite–sphalerite breccias of the Shemur copper–zinc–massive sulfide deposit (Northern Urals) are associated with Ga-enriched sphalerite, chalcopyrite, and, less commonly, pyrite (33–364, 67–363, and 4–230 g/t, respectively).  相似文献   
3.
Hydrophysical studies and mathematical modeling of ring structures during ice cover on Lake Baikal have shown that their existence at the stage of ice cover degradation is due to anticyclonic currents. Such currents can be generated as a result of local upwelling, which we associate with the rise of methane hydrates from the top layer of bottom sediments and their dissociation. Analysis of satellite images shows that the radii of ice rings range from 1300 to 2400 m, which is close to the baroclinic Rossby radius. The measured ice thicknesses in the area of the rings are in agreement with model calculations. Deep water renewal in Lake Baikal can also be associated with the rise of hydrates.  相似文献   
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5.
Doklady Earth Sciences - The results of studying the isotopic, geochemical, and TEDS properties of various generations of pyrite and pyrrhotite from the Ugakhan deposit, Bodaibo district of Irkutsk...  相似文献   
6.
Described is a system of verification of mesoscale hydrodynamic forecasts for the territory of Sochi-2014 Winter Olympic Games worked out within the framework of FROST-2014 international project. A technological line comprises the observational and model output databases, the computing verification complex, and the optional program aids for aggregation and visualization of products. The METv4.0 verification complex developed in cooperation with forecasting and research centers of the USA is used as a core. The effectiveness of the verification system is demonstrated with the COSMO model products for the period of December 1, 2011–March 31, 2012. Preliminary assessments of the model potential in forecasting the surface air temperature, the velocity of the scalar wind, and the sea-level air pressure are made with the quality score aggregation over the selected polygons of verification.  相似文献   
7.
The production of the cosmogenic radionuclides 14C, 10Be, and 36Cl in the Earth’s atmosphere under the action of powerful impulsive proton and gamma-ray events (superpowerful solar flares and Galactic gamma-ray bursts) is considered. The possible “isotopic footprint” in natural archives (the concentrations of these isotopes in dated polar ice cores and annual tree rings) has been calculated by taking into account geophysical processes. The results obtained have been applied to analyzing the anomalous increase in the concentration of radiocarbon measured in tree rings dated 774–775 AD. Arguments for the fact that the most likely cause of this increase is the high-energy emission from a Galactic gamma-ray burst are adduced.  相似文献   
8.
Lithology and Mineral Resources - Pyrite nodules were found in thin-layered sulfide ores localized at the flanks of the Talgan Cu-Zn massive sulfide deposit (South Urals) which consists of (1) an...  相似文献   
9.
For the first time, T,S-analysis was used to determine the specifics of seasonal variations in the vertical structure of Lake Baikal active layer. In the under-ice period, the active layer includes the under-ice, top winter, and upper intermediate water masses. The under-ice water mass, unlike other masses, shows an increase in mineralization to 100.74 mg/kg, which corresponds to a release of 71.1 g salt under 1 m2 of water surface in a layer 0–40 m in the process of salt freezing out during ice cover formation and accretion. In the phases of mixing (homothermy), the water masses of the active layer transform into a surface homogeneous mass. In summer and autumn, surface and upper intermediate water masses, separated by a water mass of summer thermocline can be identified. A specific feature of the summer thermocline water mass is the increased sum of ions because of an increase in HCO 3 - concentration at the decay of organic matter accumulating in the bottom part of the thermocline. The existence of the under-ice water mass and the water mass of summer thermocline was established in Lake Baikal for the first time. In the deep-water zone (>250 m), except for the bottom parts, the lower water masses (the lower intermediate and the deep) are permanent, their characteristics remaining stable during the year. The changes in the bottom water mass are due to the character of the processes of bottom water renewal.  相似文献   
10.
The Slyudyangorsk muscovite deposit in the southern Urals was explored and mined in 1926–1957. By the mid-1950s, 104 veins of quartz–feldspar pegmatites including 21 muscovite-bearing veins have been found. Pegmatites with giant black Y-bearing epidote crystals are crosscut by veins with giant muscovite crystals, which, in turn, are intersected by veins of two-mica–quartz–two-feldspar pegmatites with rare-metal and REE mineralization. Microprobe data on compositions of complex Ti–Ta–Nb oxides [fergusonite-(Y), samarskite-(Y), euxenite-(Y), polycrase-(Y), columbite-(Fe), pyrochlore supergroup] are characterized, as well as of uraninite, ilmenorutile, scheelite, Y-bearing epidote, certain sulfides and rock-forming minerals from the Slyudyanogorsk deposit. The morphology and interrelation of minerals indicate that they are the result of crystal growth in cavities rather than of metasomatic replacement of gneisses, as has been suggested earlier. Thus, it is more promising for rare-metal and REE minerals in the Slyudorudnik area to be found in igneous rocks (granitic muscovite–quartz–feldspar pegmatites with the Nb–Ta–Ti–Y–U–W–Mo mineralization) than in metasomatic rocks.  相似文献   
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