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1.
Astronomy Letters - Results of the spectroscopic observations at the 1.5-m Russian–Turkish telescope for another group of 12 X-ray sources discovered by the eROSITA telescope onboard the SRG...  相似文献   
2.
Mineralogical-geochemical data obtained on a large xenolith of spinel lherzolite from basanites of Shavaryn Tsaram volcano (Middle Pleistocene) provide evidence that the xenolith was affected by heat and fluid that came from the basalt melt and induced geochemical heterogeneity of the xenolith. Olivine crystals from the central portion of the xenolith contain much more CaO than this mineral from the peripheral zones of the xenolith as well as in xenocrystals of the host basalts. The large xenolith was unevenly annealed by the host basalt melt, and this predetermined the heterogeneous diffusion-controlled “purification” of olivine crystals from their CaO admixture. The xenolith is heterogeneously enriched in LREE and some trace elements (Zr, Hf, Nb, Th, and U), and their distribution demonstrates unclearly pronounced concentric zoning: these elements enriched the outer portions of the xenolith. The enrichment of the xenolith in LREE and other mobile trace elements is explained by their occurrence not only as structurally bound (isomorphic) components in minerals but also in the form of nonstructural admixtures (contaminant), as minute grains of compounds hosted in the interstitial space and tiny cracks cutting mineral grains. The enrichment of the xenolith in these admixtures proceeded via their infiltration-controlled introduction with fluid from the basalt along minute cracks.  相似文献   
3.
The dependence of energy consumption on air temperature for every day of the period from 1990 to 2015 is for the first time studied for mid-latitudes using the long-term observational data of the Moscow State University Meteorological Observatory. It is demonstrated that this dependence is generally descending in the Moscow region: energy consumption decreases as air temperature rises. At the same time, the energy consumption increase slows down due to energy saving in case of severe frosts, whereas the opposite trend is manifested in case of abnormally hot weather, that is, the energy consumption increase along with the air temperature rise due to additional consumption for air conditioning. The optimum temperature for energy saving is 18°C. The relationship between energy consumption and air humidity characteristics is analyzed. There is almost no link with relative humidity, while in the link with the partial pressure of water vapor, the dependence of the latter on air temperature is reflected indirectly.  相似文献   
4.
This paper considers oil-and-gas provinces and the epochs of hydrocarbon generation in Kamchatka. We distinguish the following epochs of hydrocarbon generation: the Early Mesozoic, the Early Cretaceous, the Late Cretaceous, the Early Paleogene, the Late Paleogene, the Miocene, and the Pliocene-Quaternary. We emphasize the fact that all gas generation epochs were related to deep processes, including volcanism and hydrothermal activity.  相似文献   
5.
This paper summarizes the results of combined studies in the areas of the occurrence of gas-fluid emanations in the water column, on the seafloor, and in the upper part of the sedimentary section on the northeastern slope of Sakhalin Island (Sea of Okhotsk). The phenomena typical of methane seeps were characterized in detail: the presence of acoustic anomalies, high concentrations of methane in the water and sediments, and the specific features of the sedimentary section (the textural and structural features, the character of the mineral inclusions and gas hydrates, and the chemical composition). The component composition of the gases (including the accompanying gas hydrates), which is almost free of heavy hydrocarbon homologues of methane; the light carbon isotopic compositions of the methane and carbonate concretions; and the low temperatures of the near-bottom water and sediments suggest that the occurrence of numerous methane emanations is related to gas generation in the upper part of the sedimentary sequence. No evidence was found for the existence of a deep center of gas formation within the seafloor area considered. Typical submarine mud volcanic edifices were also not found.  相似文献   
6.
New data on soft-sediment deformation in Late Pleistocene and Holocene deposits of the northwestern Kola Peninsula (Pechenga River valley) are reported and analyzed in terms of paleoseismicity implications. Soft-sediment deformation is assigned to paleoseismic triggers on the basis of special criteria. One sedimentary section in the Pechenga valley bears signature of several seismic events at the Late Pleistocene–Holocene boundary, constrained by radiocarbon dates. According to the morphology, sizes, and types of seismites, the earthquakes had an MSK-64 intensity at least VI–VII. The observed earthquake-induced deformation may be associated with tectonic subsidence of the Pechenga valley block.  相似文献   
7.
The dependence of the maximal values of the |Dst| and AE geomagnetic indices observed during magnetic storms on the value of the interplanetary electric field (E y ) was studied based on the catalog of the large-scale solar wind types created using the OMNI database for 1976–2000 [Yermolaev et al., 2009]. An analysis was performed for eight categories of magnetic storms caused by different types of solar wind streams: corotating interaction regions (CIR, 86 storms); magnetic clouds (MC, 43); Sheath before MCs (ShMC, 8); Ejecta (95); Sheath (ShE, 56); all ICME events (MC + Ejecta, 138); all compression regions Sheaths before MCs and Ejecta (ShMC + ShE, 64); and an indeterminate type of storm (IND, 75). It was shown that the |Dst| index value increases with increasing electric field E y for all eight types of streams. When electric fields are strong (E y > 11 mV m−1), the |Dst| index value becomes saturated within magnetic clouds MCs and possibly within all ICMEs (MC + Ejecta). The AE index value during magnetic storms is independent of the electric field value E y for almost all streams except magnetic clouds MCs and possibly the compressed (Sheath) region before them (ShMC). The AE index linearly increases within MC at small values of the electric field (E y < 11 mV m−1) and decrease when these fields are strong (E y > 11 mV m−1). Since the dynamic pressure (Pd) and IMF fluctuations (σB) correlate with the E y value in all solar wind types, both geomagnetic indices (|Dst| and AE) do not show an additional dependence on Pd and IMF δB. The nonlinear relationship between the intensities of the |Dst| and AE indices and the electric field E y component, observed within MCs and possibly all ICMEs during strong electric fields E y , agrees with modeling the magnetospheric-ionospheric current system of zone 1 under the conditions of the polar cap potential saturation.  相似文献   
8.
9.
Sources of modern hydrothermal systems are considered on the basis of high-precision REE data on representative samples of characteristic hydrochemical types of hydrothermal systems of the Eastern Volcanic Belt of Kamchatka and data available on modern magmatogenic fluid systems of the Kamchatka, Kuriles, and oceanic rift zones. It was found that modern high-temperature chloride-sodium hydrothermal vents have elevated REE contents and that all considered hydrochemical types of the Kamchatka hydrothermal systems are characterized by similar REE patterns. High REE contents in the hydrothermal vents with pH up to 5.0 show bimodal distribution. Correlations established between La/Yb ratios in the hydrothermal vents of various types and in the igneous rocks of the Eastern Volcanic Belt of Kamchatka are interpreted in genetic terms. A positive correlation was found between rare-earth elements, chlorine and boron contents. It was noted that all considered hydrochemical types show distinct negative europium anomaly, whereas submarine hydrothermal vents of oceanic rift zones are characterized by positive europium anomaly. It was proposed that REE was transported in the hydrothermal vents from apical zones of deep-seated magma chambers containing acid derivatives.  相似文献   
10.
This study considers variations in the physical and chemical characteristics of water in Lake Karymskii for the period from January 1996, when a phreatomagmatic eruption occurred in the lake, until 2015. Our monitoring revealed two characteristic sets of components whose behavior characterizes the hydrochemical evolution of lake water: a comparatively rapid exponential decay of the concentrations of SO4, Ca, and Mg and a slow decrease in the concentrations of Cl, Na, and K. We arrived at the conclusion that two components of the fluid flow (a fumarolic and a hydrothermal component proper) simultaneously occurred during the eruption and thus had an effect on the lake water. We adduce evidence to show that the water balance and the chemical composition of Lake Karymskii stabilized toward 2015.  相似文献   
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