New data on spherules from the region of the El’gygytgyn crater     

V. N. Smirnov  N. E. Savva  O. Yu. Glushkova 《Geochemistry International》2011,49(3):314-318

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Geochemistry of paleozoic terrigenous sediments from the Oldoi terrane, eastern Central Asian orogenic belt, as an indicator of geodynamic conditions during deposition     

Yu. N. Smirnova  A. A. Sorokin  L. I. Popeko  Yu. V. Smirnov 《Geochemistry International》2013,51(4):306-325

The analysis of the major and trace element geochemistry of Paleozoic terrigenous sediments from the Oldoi terrane, eastern Central Asian orogenic belt, supports a predominantly felsic source consisting of granites and recycled sediments. The geological data suggest that detrital material could be derived from Early Paleozoic granitoids, which were identified within tectonic blocks in the Silurian and Devonian terrigenous successions. The analysis of conventional discrimination diagrams indicates that the initial stage was marked by deposition along a passive continental margin, which continued in island-arc or active continental margin environments. This interpretation is consistent with geological evidence, such as the presence of volcanic interlayers and lenses in the Middle-Late Devonian successions and granitoids with ages of 386 +/- 10 and 371+/- 5.5 Ma. The timing of changes in geodynamic settings constrained by tectonic reconstructions corresponds to the age of the inception of the Norovlya continental-margin magmatic arc.  相似文献   

Active Galactic Nuclei among Polar-Ring Galaxies     

Smirnov  D. V.  Reshetnikov  V. P. 《Astronomy Letters》2020,46(8):501-508

Astronomy Letters - Based on SDSS data, we consider the fraction of active galactic nuclei among polar-ring galaxies. We have found evidence for an excess of Seyfert galaxies and LINERS among...  相似文献   

Simulating the Propagation of Infrasonic Waves and Estimating the Energy of the Chelyabinsk Meteoroid Explosion Observed on February 15, 2013     

S.?N.?KulichkovEmail author  O.?Ye.?Popov  K.?V.?Avilov  I.?P.?Chunchuzov  O.?G.?Chkhetiani  A.?A.?Smirnov  V.?I.?Dubrovin  A.?A.?Mishenin 《Izvestiya Atmospheric and Oceanic Physics》2018,54(3):293-303

Results obtained from simulating the propagation of infrasonic waves from the Chelyabinsk meteoroid explosion observed on February 15, 2013, are given. The pseudodifferential parabolic equation (PDPE) method has been used for calculations. Data on infrasonic waves recorded at the IS31 station (Aktyubinsk, Kazakhstan), located 542.7 km from the likely location of the explosion, have been analyzed. Six infrasonic arrivals (isolated clearly defined pulse signals) were recorded. It is shown that the first “fast” arrival (F) corresponds to the propagation of infrasound in a surface acoustic waveguide. The rest of the arrivals (T1–T5) are thermospheric. The agreement between the results of calculations based on the PDPE method and experimental data is satisfactory. The energy E of the explosion has been estimated using two methods. One of these methods is based on the law of conservation of the acoustic pulse I, which is a product of the wave profile area S/2 of the signal under analysis and the distance to its source E _I [kt] = 1.38 × 10^–10 (I [kg/s])^1.482. The other method is based on the relation between the energy of explosion and the dominant period T of recorded signal E _T [kt] = 1.02 × (T [s]²/σ)^3/2, where σ is the dimensionless distance determining the degree of nonlinear effects during the propagation of sound along ray trajectories. According to the data, the explosion energy E _I,T ranges from 1.87 to 32 kt TNT.  相似文献   

Bistatic Radar Detection in the Luna-Resurs Mission     

O.?V.?YushkovaEmail author  A.?L.?Gavrik  V.?N.?Marchuk  V.?V.?Yushkov  V.?M.?Smirnov  M.?A.?Laptev  B.?V.?Chernyshev  I.?N.?Dutyshev  V.?P.?Lebedev  A.?V.?Medvedev  A.?A.?Petrukovich 《Solar System Research》2018,52(4):287-300

An overview of radiophysical investigations of the lunar soil and plasma shell by active radar detection with the use of spacecraft is presented. The possibility is analyzed of conducting bistatic measurements using the Irkutsk Incoherent Scattering Radar and the onboard radar system RLK-L which is being developed for the orbital station of the Luna-Resurs mission.  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   

Response of the electric state of the surface atmosphere to the geomagnetic storm of April 5, 2010     

S. E. Smirnov 《Doklady Earth Sciences》2014,456(1):622-626

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An Analysis of the Content of Large Bodies in Meteor and Fireball Streams     

S. I. Barabanov  M. A. Smirnov 《Solar System Research》2005,39(3):231-238

The issue of the presence of meter- and decameter-sized bodies in meteor and fireball streams is of fundamental importance in the context of the theory of disintegration of parent bodies. Our observations, which have been carried out since 1995, indicate that such bodies are present in the Perseid, α-Capricornid, Leonid, and Coma-Berenicid meteoric streams. A catalogue is presented here for the parameters of the detected bodies. The spatial density of the meter-sized bodies is estimated based on the observational material. Within the errors, our estimates agree with the estimates based on the extrapolation of meteor and fireball data. An analysis of the observations suggests some inferences on the structure of the streams under study.__________Translated from Astronomicheskii Vestnik, Vol. 39, No. 3, 2005, pp. 263–271.Original Russian Text Copyright © 2005 by Barabanov, Smirnov.  相似文献   

Abiotic ammonium formation in the presence of Ni-Fe metals and alloys and its implications for the Hadean nitrogen cycle     

Alexander Smirnov  Douglas Hausner  Richard Laffers  Daniel R Strongin  Martin AA Schoonen 《Geochemical transactions》2008,9(1):1-20

Experiments with dinitrogen-, nitrite-, nitrate-containing solutions were conducted without headspace in Ti reactors (200°C), borosilicate septum bottles (70°C) and HDPE tubes (22°C) in the presence of Fe and Ni metal, awaruite (Ni₈₀Fe₂₀) and tetrataenite (Ni₅₀Fe₅₀). In general, metals used in this investigation were more reactive than alloys toward all investigated nitrogen species. Nitrite and nitrate were converted to ammonium more rapidly than dinitrogen, and the reduction process had a strong temperature dependence. We concluded from our experimental observations that Hadean submarine hydrothermal systems could have supplied significant quantities of ammonium for reactions that are generally associated with prebiotic synthesis, especially in localized environments. Several natural meteorites (octahedrites) were found to contain up to 22 ppm N_tot. While the oxidation state of N in the octahedrites was not determined, XPS analysis of metals and alloys used in the study shows that N is likely present as nitride (N^3-). This observation may have implications toward the Hadean environment, since, terrestrial (e.g., oceanic) ammonium production may have been supplemented by reduced nitrogen delivered by metal-rich meteorites. This notion is based on the fact that nitrogen dissolves into metallic melts.  相似文献   

Seiche oscillations in the Nakhodka Gulf     

S. V. Smirnov 《Russian Meteorology and Hydrology》2016,41(1):57-62

Spatiotemporal parameters of barotropic seiche oscillations in the Nakhodka Gulf in the Sea of Japan are considered using the spectral finite-difference model. The finite-difference approximation of shallow water equations is carried out at the irregular triangular spatial grid. The sets of periods and spatial structures of seiche oscillations corresponding to the strongly pronounced maxima of energy spectrum of sea level data from Nakhodka station of the Russian tsunami warning service are computed and presented.  相似文献