Color of the Corona Continuum of July 11, 1991     

Kim  I. S.  Krusanova  N. L.  Popov  V. V.  Osokin  A. R.  Mironova  I. V. 《Geomagnetism and Aeronomy》2020,60(4):441-445

Geomagnetism and Aeronomy - The color of the coronal continuum was determined from observations in order to search for manifestations of coronal expansion. A brief review of studies determining the...  相似文献   

Influence of Oxygen Ions on the Structure of the Thin Current Sheet in the Earth’s Magnetotail     

Domrin  V. I.  Malova  Kh. V.  Popov  V. Yu.  Grigorenko  E. E.  Petrukovich  A. A. 《Geomagnetism and Aeronomy》2020,60(2):171-183

Geomagnetism and Aeronomy - During geomagnetic substorms, the current sheet in the Earth’s magnetotail can transversely reduce in thickness from a few radii of the Earth (RE) to one to...  相似文献   

Paleomagnetic study of the Tunguska catastrophe epicenter     

O. G. Gladysheva  V. V. Popov 《Geomagnetism and Aeronomy》2016,56(2):229-238

The Tunguska catastrophe occurred in the area of the East Siberian magnetic anomaly on June 30, 1908. The epicenter of the explosive destruction of the Tunguska cosmic body (TCB) was above the central neck of a paleovolcano (Mt. Stoikovich). According to the paleomagnetic data available, the bedrocks on the top of Mt. Stoikovich carry remanent magnetization, which is substantially higher than that in rocks from neighboring mountains. Analysis of the results of paleomagnetic measurements of rock samples collected in the vicinity of the Tunguska catastrophe epicenter showed that the destruction of the cosmic body was accompanied by the formation of multidirectional magnetic fields, which provide disturbances spreading over a distance of 25 km from the epicenter. The chaotic distribution pattern of magnetization vectors measured in the soil in the vicinity of the Tunguska catastrophe epicenter confirms the previously expressed assumption that destruction of the TCB was accompanied with multiple discharges. According to this, we can conclude that the matter of the Tunguska cosmic body was dispersed around the epicenter in a zone approximately 25 km in diameter.  相似文献   

Solar-activity cycle from observations of magnetic characteristics of prominences     

I. S. Kim  I. V. Alekseeva  I. V. Mironova  A. R. Osokin  V. V. Popov  E. Z. Suyunova 《Geomagnetism and Aeronomy》2016,56(8):993-997

According to measurements of the magnetic fields in quiescent prominences carried out by different teams in 1964–1989, the maximum values of the field correspond to the minimum values of the Wolf numbers averaged through the corresponding periods of observations. It has been shown that the synoptic noneclipse 2D linear polarimetry of quiescent Hα-prominences can be actually implemented; this method is based on the use of a coronagraph with a primary-optics diameter equal to or larger than 100 mm, a narrow-band filter with FWHM ≤ 0.4 nm, a standard linear polariod, and a high-precision linear polarimetric technique.  相似文献   

Late Vendian postcollisional leucogranites of Yenisei Ridge     

A. D. Nozhkin  I. I. Likhanov  V. V. Reverdatto  T. B. Bayanova  S. V. Zinoviev  P. S. Kozlov  N. V. Popov  N. V. Dmitrieva 《Doklady Earth Sciences》2017,474(2):674-679

The Late Vendian (540–550 Ma) U–Pb zircon age of postcollisional granitoids in the Osinovka Massif was obtained for the first time. The Osinovka Massif is located in rocks of the island-arc complex of the Isakovka Terrane, in the northwestern part of the Sayany–Yenisei accretion belt. These events stand for the final stage of the Neoproterozoic history of the Yenisei Ridge, related to the completing accretion of the oceanic crust fragments and the beginning of the Caledonian orogenesis. The petrogeochemical composition and the Sm–Nd isotopic characteristics support the fact that the granitoid melt originated from a highly differentiated continental crust of the southwestern margin of the Siberian Craton. Hence, the granite-bearing Late Riphean island-arc complexes were thrust over the craton margin at a distance considerably exceeding the dimensions of the Osinovka Massif.  相似文献   

Environmental Radioxenon Levels in Europe: a Comprehensive Overview     

Paul R. J. Saey  Clemens Schlosser  Pascal Achim  Matthias Auer  Anders Axelsson  Andreas Becker  Xavier Blanchard  Guy Brachet  Luis Cella  Lars-Erik De Geer  Martin B. Kalinowski  Gilbert Le Petit  Jenny Peterson  Vladimir Popov  Yury Popov  Anders Ringbom  Hartmut Sartorius  Thomas Taffary  Matthias Zähringer 《Pure and Applied Geophysics》2010,167(4-5):499-515

Activity concentration data from ambient radioxenon measurements in ground level air, which were carried out in Europe in the framework of the International Noble Gas Experiment (INGE) in support of the development and build-up of a radioxenon monitoring network for the Comprehensive Nuclear-Test-Ban Treaty verification regime are presented and discussed. Six measurement stations provided data from 5 years of measurements performed between 2003 and 2008: Longyearbyen (Spitsbergen, Norway), Stockholm (Sweden), Dubna (Russian Federation), Schauinsland Mountain (Germany), Bruyères-le-Châtel and Marseille (both France). The noble gas systems used within the INGE are designed to continuously measure low concentrations of the four radioxenon isotopes which are most relevant for detection of nuclear explosions: ^131mXe, ^133mXe, ¹³³Xe and ¹³⁵Xe with a time resolution less than or equal to 24 h and a minimum detectable concentration of ¹³³Xe less than 1 mBq/m³. This European cluster of six stations is particularly interesting because it is highly influenced by a high density of nuclear power reactors and some radiopharmaceutical production facilities. The activity concentrations at the European INGE stations are studied to characterise the influence of civilian releases, to be able to distinguish them from possible nuclear explosions. It was found that the mean activity concentration of the most frequently detected isotope, ¹³³Xe, was 5–20 mBq/m³ within Central Europe where most nuclear installations are situated (Bruyères-le-Châtel and Schauinsland), 1.4–2.4 mBq/m³ just outside that region (Stockholm, Dubna and Marseille) and 0.2 mBq/m³ in the remote polar station of Spitsbergen. No seasonal trends could be observed from the data. Two interesting events have been examined and their source regions have been identified using atmospheric backtracking methods that deploy Lagrangian particle dispersion modelling and inversion techniques. The results are consistent with known releases of a radiopharmaceutical facility.  相似文献   

Distribution of Ixodes ricinus L., 1758 and Ixodes persulcatus Shulze, 1930 (Parasitoformes,Ixodidae) in Russia and adjacent countries in view of observable climate changes     

Yasyukevich  V. V.  Kazakova  E. V.  Popov  I. O.  Semenov  S. M. 《Doklady Earth Sciences》2009,427(2):1030-1034

Possible changes in the area inhabited by the ticks Ixodes ricinus and Ixodes persulcatus, the main transmitters of tick-borne encephalitis and Lyme disease in Russia, caused by temperature changes in 1976–2005 compared to 1946–1975 are discussed. It is shown that these changes could result in some areal expansion of these species. In the European part of Russia, I. ricinus expanded its areal boundaries to the east 100–300 km. I. persulcatus expanded its areal in the Asian part of Russia. Its boundary moved to the north and northeast 100–300 km. Areal expansion both of species has not been observed.  相似文献   

Kyanite–sillimanite metamorphism of the Precambrian complexes,Transangarian region of the Yenisei Ridge     

I.I. Likhanov  V.V. Reverdatto  P.S. Kozlov  N.V. Popov 《Russian Geology and Geophysics》2009,50(12):1034-1051

Four Precambrian metamorphic complexes in the vicinity of regional faults in the Transangarian region of the Yenisei Ridge were examined. Based on geothermobarometry and P-T path calculations, our geological and petrological studies showed that the Neoproterozoic medium-pressure metamorphism of the kyanite–sillimanite type overprinted regionally metamorphosed low-pressure andalusite-bearing rocks at about 850 Ma. A positive correlation between rock ages and P-T estimates for the kyanite-sillimanite metamorphism provide evidence of the regional structural and tectonic heterogeneity. The medium-pressure metamorphism was characterized by (1) the development of deformational structures and textures, and kyanite-bearing blastocataclasites (blastomylonites) with sillimanite, garnet, and staurolite after andalusite-bearing regional metamorphic rocks; (2) insignificant apparent thickness of the zone of medium-pressure zonal metamorphism (from 2.5 to 7 km), which was localized in the vicinity of the overthrusts; (3) a low metamorphic field gradient during metamorphism (from 1–7 to 12 °C/km); and (4) a gradual increase in lithostatic pressure towards the thrust faults. These specific features are typical of collisional metamorphism during overthrusting of continental blocks and are evidence for near-isothermal loading. This event was justified within the framework of the crustal tectonic thickening model via rapid overthrusting and subsequent rapid uplifting and erosion. The results obtained allowed us to consider medium-pressure kyanite-bearing metapelites as a product of collision metamorphism, formed either by unidirectional thrusting of rock blocks from Siberian craton onto the Yenisei Ridge in the zones of regional faults (Angara, Mayakon, and Chapa areas) or by opposite movements in the zone of splay faults of higher orders (Garevka area).  相似文献   

Two stages of high-pressure metamorphism in the Main Uralian Fault area (northern Urals)     

G.A. Petrov  Yu.L. Ronkin  N.V. Popov  N.I. Tristan  P.S. Kozlov 《Russian Geology and Geophysics》2009,50(1):43-45

Metamorphism in the northern sector of the Main Uralian Fault (MUF) area, northern Urals, is considered by the example of the Salatim glaucophane-schist and Belokamenka kyanite-staurolite complexes. New isotope-geochronological dates for metamorphic rocks of the MUF area are presented. The obtained data evidence the existence of two metamorphic events, of Early and Late Devonian ages, which apparently correspond to the wedging-up of subduction paleozones.  相似文献   

The first find of rapakivi granite in the Yenisei ridge: Age, <Emphasis Type="Italic">PT</Emphasis> conditions,and tectonic settings     

I. I. Likhanov  V. V. Reverdatto  N. V. Popov  P. S. Kozlov 《Doklady Earth Sciences》2012,443(1):365-370

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