Initiation of acoustic emission in fluid-saturated sandstone samples     

V. B. Lapshin  A. V. Patonin  A. V. Ponomarev  M. G. Potanina  V. B. Smirnov  S. M. Stroganova 《Doklady Earth Sciences》2016,469(1):705-709

A rock behavior experiment with uniaxial compression revealed the effect of acoustic activity in loaded fluid-saturated Berea sandstone samples in response to an electric current. It is established that it is substantially intensified in periods of the current impact and decreases after its cut-off. The current impact also results in a growth of radial deformation indicating an increase in the sample volume. The effect of acoustic activation increases in response to increased heat emitted by the electric current during its flow through the sample, which allows the discovered effect to be explained by initiation of its destruction due to thermal expansion of the fluid in rock interstices and fissures.  相似文献   

Geology and mineralogy of the Alakha spodumene granite porphyry deposit,Gorny Altai,Russia     

I. Yu. Annikova  A. G. Vladimirov  S. Z. Smirnov  O. A. Gavryushkina 《Geology of Ore Deposits》2016,58(5):404-426

The Alakha lithium–tantalum deposit in the southern Altai, Russia, is represented by a stock of spodumene-bearing granite porphyry localized in the Kalba–Narym–Koktogai lithium–tantalum rare-metal granitic belt, unique in extent (more than 1000 km). This belt is a part of the Altai accretionary–collisional system. Judging from forecasting, the Alakha deposit can be regarded as an uneroded proxy of a pegmatite body both in dimensions and mean Li₂O and Ta₂O₅ contents (0.98 wt % and 114 ppm, respectively); however, the oregenerating potential of this deposit remains insufficiently studied and had not yet been claimed. In this paper, we attempt to fill this gap with a detailed mineralogical study, which allows us to provide insights into the crystallization of Li-bearing high-silicic magma and redistribution of components during magmatic and postmagmatic processes. Accessory mineral assemblages in muscovite–spodumene–K-feldspar granite porphyry and muscovite albitite—the main petrographic rock varieties of the Alakha stock—turned out to be almost identical. A significant similarity in the chemistry of major rock-forming minerals is established for spodumene granite porphyry of the Alakha stock and spodumene pegmatites from large deposits, which makes it possible to suggest that they are close in the petrogenetic mechanism of their formation. The mineral assemblages of muscovite albitite in the apical portion of the Alakha stock are connected by gradual transition with those of spodumene granite porphyry. Such a transition is caused by postmagmatic metasomatic alteration of the latter.  相似文献   

Estimating the Contributions of the Atlantic Multidecadal Oscillation and Variations in the Atmospheric Concentration of Greenhouse Gases to Surface Air Temperature Trends from Observations     

I. I. Mokhov  D. A. Smirnov 《Doklady Earth Sciences》2018,480(1):602-606

We have quantitatively estimated the contributions of anthropogenic forcing characterized by variations in the atmospheric content of greenhouse gases and of natural variability characterized by the Atlantic Multidecadal Oscillation to the trends of global surface air temperature from observations since the middle of the nineteenth century on the basis of three-component autoregressive models.  相似文献   

Crust structure of the northeastern Barents Sea basin area     

A.L. Piskarev  A.A. Kireev  V.A. Savin  O.E. Smirnov 《Russian Geology and Geophysics》2018,59(7):803-812

Processing of data from regional geophysical surveys completed in the northern Barents Sea has provided updates to gravity and magnetic databases, structural maps of seismic interfaces, and positions of anomaly sources, which made a basis for 3D density and magnetic models of the crust. The new geological and geophysical results placed constraints on the boundaries between basement blocks formed in different settings and on the contours of deposition zones of different ages in the northeastern Barents Sea. The estimated thicknesses of sedimentary sequences that formed within certain time spans record the deposition history of the region. There is a 20-50 km wide deep suture between two basins of Mesozoic and Paleozoic ages in the eastern part of the region, where pre-Late Triassic reflectors have no clear correlation. The suture slopes eastward at a low angle and corresponds to a paleothrust according to seismic and modeling data. In the basement model, the suture is approximated by a zone of low magnetization and density, which is common to active fault systems. The discovery of the suture has important geological and exploration implications.  相似文献   

Tropospheric temperature interannual variations associated with decadal changes in the North Atlantic Oscillation     

G. P. Kurbatkin  V. D. Smirnov 《Izvestiya Atmospheric and Oceanic Physics》2010,46(4):401-413

This paper studies the causes and mechanisms of the formation of extreme anomalies in the tropospheric temperature associated with the North Atlantic Oscillation (NAO). Our approach is based on understanding that, in the annual cycle, continental-scale tropospheric temperature anomalies (planetary waves with longitudinal wave numbers of 1–3) can both intensify under the direct action of heat inflow as an energy source for these anomalies (radiation cooling/heating) and weaken as a result of the destructive action of heat inflow under temperature advections with the opposite (to the heat inflow) sign [4, 5]. According to the monthly mean data of the NCEP/NCAR reanalysis over the 40-year period, seasonal air temperature anomalies have been studied at the level 850 hPa (T ₈₅₀) in different regions of Eurasia. It has been confirmed that the negative NAO phase in winter is favorable for preserving negative T ₈₅₀ anomalies in the east of the continent at this time of year, whereas the positive NAO phase is favorable for negative T ₈₅₀ anomalies in the west. However, it has been revealed that this dependence was critically violated during the winter seasons approximately two years before an extreme event. This was explained by the fact that, in those years, the NAO influence on winter T ₈₅₀ anomalies was limited. This paper formally considers a certain mechanism of anomalous heat inflow as an energy source for these anomalies with functions of the formation (intensification) of negative T ₈₅₀ anomalies in winter and positive T ₈₅₀ anomalies in summer, as well as with a function of the limitation of the influence of the predominant dynamic mode on some regions of the continent. It is shown that, in the 1960s, T ₈₅₀ anomalies with negative NAO indices in the east of the continent were governed by a hypothetic mechanism of heat inflow as an energy source for anomalies; in 1980s, at prolonged positive NAO indices, T ₈₅₀ anomalies in the west of the continent could also be governed by this mechanism. This paper, within the accepted degree of detail, demonstrates the process of limitation of the NAO influence in some years (1966, 1967, 1987, and 1988), which leads to an unbalance of the anomalies and a possible extreme phenomenon. It is demonstrated that, in some seasons, the anomalies were not governed by the hypothetic mechanism of the heat inflow under the action of large NAO changes and a complete upset of the annual cycle of anomalies. Determining the first indicators of the unbalance, which can lead to extreme anomalies, is shown to be difficult if it is based only on an analysis of winter seasons (as is the case with most of the works) without invoking the annual trends of the tropospheric temperature and the NAO index.  相似文献   

Diurnal variations in the electrical field intensity under smoke from forest fires     

I. I. Ippolitov  M. V. Kabanov  P. M. Nagorskii  Yu. A. Pkhalagov  S. V. Smirnov 《Doklady Earth Sciences》2013,453(1):1137-1140

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Altitude profile of H in the atmosphere of Venus from Lyman α observations of Venera 11 and Venera 12 and origin of the hot exospheric component     

J.L. Bertaux  V.M. Lepine  V.G. Kurt  A.S. Smirnov 《Icarus》1982,52(2):221-244

Two extreme ultraviolet (EUV) spectrophotometers flown in December 1978 on Venera 11 and Venera 12 measured the hydrogen Lyman α emission resonantly scattered in the atmosphere of Venus. Measurements were obtained across the dayside of the disk, and in the exosphere up to 50,000 km. They were analyzed with spherically symmetric models for which the radiative transfer equation was solved. The H content of the Venus atmosphere varies from optically thin to moderately thick regions. A shape fit at the bright limb allows one to determine the exospheric temperature T_c and the number density n_c independently of the calibration of the instrument or the exact value of the solar flux. The dayside exospheric temperature was measured for the first time in the polar regions, with T_c = 300 ± 25°K for Venera 11 (79°S) and T_c = 275 ± 25°K (59°S) for Venera 12. At the same place, the density is n_c = 4_?2⁺³ × 10⁴ atom.cm^?3, and the integrated number density N_t from 250 to 110 km (the level of CO₂ absorption) is 2.1 × 10¹² atom.cm^?2, a factor of 3 to 6 lower than that predicted in aeronomical models. This probably indicates that the models should be revised in the content of H-bearing molecules and should include the effect of dynamics. Across the disk the value of N_t decreases smoothly with a total variation of two from the morning side to the afternoon side. Alternately it could be a latitude effect, with less hydrogen in the polar regions. The nonthermal component if clearly seen up to 40,000 km of altitude. It is twice as abundant as at the time of Mariner 10 (solar minimum). Its radial distribution above 4000 km can be simulated by an exospheric distribution with T = 10³⁰K and n = 10³ atom.cm^?3 at the exobase level. However, there are less hot atoms between 2000 and 4000 km than predicted by an ionospheric source. A by-product of the analysis is a determination of a very high solar Lyman α flux of 7.6 × 10¹¹ photons (cm² sec Å)^?1 at line center (1 AU) in December 1978.  相似文献   

On the atomic constants of ReI     

Yu. M. Smirnov 《Astronomy Reports》2003,47(3):240-247

We have experimentally studied the excitation of the rhenium atom by collisions with slow monoenergetic electrons and measured 47 excitational cross sections for lines of ReI at an electron energy of 50 eV. Previously published information about the probabilities of radiative transitions of ReI is analyzed. The data for two experimental studies of the ratios Iλ/gA for transitions with a common upper level differ by three orders of magnitude.  相似文献   

Heat flow map of the European part of the U.S.S.R.     

R. I. Kutas  E. A. Lubimova  Ya. B. Smirnov 《Pure and Applied Geophysics》1978,117(1-2):104-108

A heat flow isoline map is presented. Low and relatively constant heat flow has been observed in the old shield areas of the East European Platform (25–40 mW/m²). Increased heat flow (>50 mW/m²) has been found in the Dniepr-Donetz depression. The area south of the East European Platform is characterized by highly variable heat flow (55–100 mW/m²). Some geophysical implications are discussed.  相似文献   

Study of interaction of ELF–ULF range (0.1–200 Hz) electromagnetic waves with the earth’s crust and the ionosphere in the field of industrial power transmission lines (FENICS experiment)     

A. A. Zhamaletdinov  A. N. Shevtsov  E. P. Velikhov  A. A. Skorokhodov  V. E. Kolesnikov  T. G. Korotkova  P. A. Ryazantsev  B. V. Efimov  V. V. Kolobov  M. B. Barannik  P. I. Prokopchuk  V. N. Selivanov  Yu. A. Kopytenko  E. A. Kopytenko  V. S. Ismagilov  M. S. Petrishchev  P. A. Sergushin  P. E. Tereshchenko  B. V. Samsonov  M. A. Birulya  M. Yu. Smirnov  T. Korja  Yu. M. Yampolski  A. V. Koloskov  N. A. Baru  S. V. Poljakov  A. V. Shchennikov  G. I. Druzhin  W. Jozwiak  J. Reda  Yu. G. Shchors 《Izvestiya Atmospheric and Oceanic Physics》2015,51(8):826-857

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