CCD Polarimetry of Near-Earth Asteroid 2014 JO25 and Comet 41P/Tuttle–Giacobini–Kresák at the Prime Focus of the 2.6-m Shajn Telescope of the Crimean Astrophysical Observatory     

Rumyantsev  V. V.  Kiselev  N. N.  Ivanova  A. V. 《Solar System Research》2019,53(2):91-97

The results of the first polarimetric measurements of near-Earth asteroid 2014 JO₂₅ and comet 41P/Tuttle-Giacobini-Kresák performed on April 19, 2017, with a CCD sensor at the prime focus (f/3.85) of the 2.6-m Shajn Telescope of the Crimean Astrophysical Observatory in the R filter are reported. The degree of linear polarization of the asteroid is P = 2.69 ± 0.44% at a phase angle of 55.6°, which is typical of an S-type asteroid. Its geometric albedo is ρ_v ≈ 0.2. A digital filter applied to the direct image of the comet reveals a jet and a tail directed toward the Sun (PA = 45.1°) and away from it (PA = 241.2°), respectively, in the coma. The maximum degree of linear polarization in the near-nucleus region of the comet is 18% at a phase angle of 69.8°. The polarization decreases to 16.2–10.7% in coma regions with a radius of 865–4856 km. Various factors affecting the maximum degree of polarization and the polarization-degree distribution over the coma are discussed.

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Structural Control of Gold Mineralization of the Central Part of the Malouralsky Volcano–Plutonic Belt (the Polar Urals), Based on an Analysis of Multispectral Images from the Landsat 8 Spacecraft     

Ivanova  J. N.  Vyhristenko  R. I.  Vikentyev  I. V. 《Izvestiya Atmospheric and Oceanic Physics》2020,56(12):1537-1545

Izvestiya, Atmospheric and Oceanic Physics - The central part of the Malouralsky volcanic–plutonic belt, which includes the Manyukuyu–Vorchatinsky ore cluster, is analyzed using...  相似文献   

Transport of Air Masses and Pollutants to the Russian Arctic Islands (1986<Emphasis Type="Bold">–</Emphasis>2016): Long-Term,Interannual, and Seasonal Variations     

A. A. Vinogradova  Yu. A. Ivanova 《Izvestiya Atmospheric and Oceanic Physics》2018,54(7):688-699

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Subpollen Particles as Atmospheric Cloud Condensation Nuclei     

Mikhailov  E. F.  Ivanova  O. A.  Nebosko  E. Yu.  Vlasenko  S. S.  Ryshkevich  T. I. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(4):357-364

Izvestiya, Atmospheric and Oceanic Physics - Bioparticles constitute a significant fraction of atmospheric aerosol. Their size range varies from nanometers (macromolecules) to hundreds of...  相似文献   

Study of Lateral Sedimentation in the Western Atlantic on Cruise 53 of the R/V Akademik Ioffe     

Ivanova  E. V.  Murdmaa  I. O.  Borisov  D. G.  Ovsepyan  E. A.  Simagin  N. V.  Mutovkin  A. D.  Nemchenko  N. V.  Kornilova  M. O.  Sud’in  V. V.  Novikov  Yu. V. 《Oceanology》2018,58(6):932-934

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Granitoids of the Kongo Magmatic Zone of the Omolon Massif (Northeastern Russia): Rock Composition,Age, and Geodynamic Setting     

Glukhov  A. N.  Kotov  A. B.  Priymenko  V. V.  Sal’nikova  E. B.  Ivanova  A. A.  Plotkina  Yu. V.  Fedoseenko  A. M. 《Geotectonics》2022,56(2):178-190

Geotectonics - In our study we analyzed the composition of granitoid rocks within the Kongo magmatic zone of the Omolon median mass. The studied calc-alkaline granitoids cut through the Early...  相似文献   

The Tolud Burst of Seismicity and the Earthquake of November 30, 2012 (<Emphasis Type="Italic">M</Emphasis><Subscript>C</Subscript> = 5.4, <Emphasis Type="Italic">M</Emphasis><Subscript>W</Subscript> = 4.8) that Accompanied the Start of the 2012‒2013 Tolbachik Eruption     

Yu. A. Kugaenko  V. M. Pavlov  E. I. Ivanova  I. R. Abubakirov  V. A. Saltykov 《Journal of Volcanology and Seismology》2017,11(6):419-433

This paper reports a study of the Tolud earthquake sequence; the sequence was a burst of shallow seismicity between November 28 and December 7, 2012; it accompanied the initial phase in the Tolbachik Fissure Eruption of 2012?2013. The largest earthquake (the Tolud earthquake of November 30, 2012, to be referred to as the Tolud Earthquake in what follows, with K_S = 11.3, M_L = 4.9, M_C = 5.4, and M_W = 4.8) is one of the five larger seismic events that have been recorded at depths shallower than 10 km beneath the entire Klyuchevskoi Volcanic Cluster in 1961?2015. It was found that the Tolud earthquake sequence was the foreshock–aftershock process of the Tolud Earthquake. This is one of the larger seismicity episodes ever to have occurred in the volcanic areas of Kamchatka. Data of the Kamchatka seismic stations were used to compute some parameters for the Tolud Earthquake and its largest (M_L = 4.3) aftershock; the parameters include the source parameters and mechanisms, and the moment magnitudes, since no information on these is available at the world seismological data centers. The focal mechanisms for the Tolud Earthquake and for its aftershock are consistent with seismic ruptures at a tension fault in the rift zone. Instrumental data were used to estimate the intensity of shaking due to the Tolud Earthquake. We discuss the sequence of events that was a signature of the time-dependent seismic and volcanic activity that took place in the Tolbachik zone in late November 2012 and terminated in the Tolud burst of seismicity. Based on the current ideas of the tectonics and magma sources for the Tolbachik volcanic zone, we discuss possible causes of these earthquakes.  相似文献   

New data on the Late Cenozoic basaltic volcanism in Syria,applied to its origin     

V.G. Trifonov  A.E. Dodonov  E.V. Sharkov  D.I. Golovin  I.V. Chernyshev  V.A. Lebedev  T.P. Ivanova  D.M. Bachmanov  M. Rukieh  O. Ammar  H. Minini  A.-M. Al Kafri  O. Ali 《Journal of Volcanology and Geothermal Research》2011,199(3-4):177-192

New data on geology and 21 K–Ar dates of the Late Oligocene–Quaternary basalts in Syria, combined with analysis of the new and previous data are used to reconstruct the volcanic history and relations between it and tectonic events. Volcanism began at the end of Oligocene (26–24 Ma) and was concentrated in the Late Oligocene–Early Miocene along a N-trending band, which stretches from the Jebel Arab (Harrat Ash Shaam) up to Kurd Dagh and southern Turkey. Activity waned in the Middle Miocene (17–12 Ma), but was resumed in the same band in the Tortonian and increased in the Messinian and Early Pliocene (6.3–4 Ma), when volcanism spread to the Shin Plateau and its coastal extension. After a brief hiatus ～ 4–3.5 Ma, volcanism became still more intensive and spread from the N-trending band to the east into the northern margin of the Mesopotamian Foredeep and to the west into the Dead Sea Transform zone. Additional eruptions continued into the Holocene.Volcanism lasted > 25 million years in the Jebel Arab Highland and > 15 million years in the Aleppo Plateau. The long duration of volcanism in the same parts of the moving Arabian plate and absence of records of one-way migration of the activity mean that the magmatic sources moved together with the plate, i.e., they were situated within the lithosphere mantle. Coincidence of the tectonic and volcanic stages of the Arabian plate development proves that volcanic activity depended on the geodynamic situation, caused by the plate motion. Situated within the lithosphere, magmatic sources within this transverse band were possibly caused by thermal and deforming influences of the asthenospheric lateral flow, moved laterally from the Ethiopia–Afar deep superplume.  相似文献   

Snow carrots after the Chelyabinsk event and model implications for highly porous solar system objects          下载免费PDF全文

Robert Luther  Natalia Artemieva  Marina Ivanova  Cyril Lorenz  Kai Wünnemann 《Meteoritics & planetary science》2017,52(5):979-999

After the catastrophic disruption of the Chelyabinsk meteoroid, small fragments formed funnels in the snow layer covering the ground. We constrain the pre‐impact characteristics of the fragments by simulating their atmospheric descent with the atmospheric entry model. Fragments resulting from catastrophic breakup may lose about 90% of their initial mass due to ablation and reach the snow vertically with a free‐fall velocity in the range of 30–90 m s^?1. The fall time of the fragments is much longer than their cooling time, and, as a consequence, fragments have the same temperature as the lower atmosphere, i.e., of about ?20 °C. Then, we use the shock physics code iSALE to model the penetration of fragments into fluffy snow, the formation of a funnel and a zone of denser snow lining its walls. We examine the influence of several material parameters of snow and present our best‐fit model by comparing funnel depth and funnel wall characteristics with observations. In addition, we suggest a viscous flow approximation to estimate funnel depth dependence on the meteorite mass. We discuss temperature gradient metamorphism as a possible mechanism which allows to fill the funnels with denser snow and to form the observed “snow carrots.” This natural experiment also helps us to calibrate the iSALE code for simulating impacts into highly porous matter in the solar system including tracks in the aerogel catchers of the Stardust mission and possible impact craters on the 67P/Churyumov‐Gerasimenko comet observed recently by the Rosetta mission.  相似文献   

The thermodynamics of arsenates,selenites, and sulfates in the oxidation zone of sulfide ores. XI. Solubility of synthetic chalcomenite analog and zinc selenite at 25°C     

M. V. Charykova  V. G. Krivovichev  N. M. Ivanova  V. V. Semenova 《Geology of Ore Deposits》2015,57(8):691-698

The aim of this study is the synthesis of CuSeO₃·2H₂O (chalcomenite analog), ZnSeO₃·2H₂O, and ZnSeO₃·H₂O and the investigation of their solubility in water. CuSeO₃·2H₂O has been synthesized from solutions of Cu nitrate and Na selenite, while Zn selenites were synthesized from solutions of Zn nitrate and Na selenite. The samples obtained have been examined with X-ray diffraction and infrared and Raman spectroscopy. The solubility has been determined using the isothermal saturation method in ampoules at 25°C. The solubility has been calculated using the Geochemist’s Workbench (GMB 9.0) software package. Solubility products have been calculated for CuSeO₃·2H₂O (10^–10.63), ZnSeO₃·2H₂O (10^–8.35), and ZnSeO₃·H₂O (10^–7.96). The database used comprises thermodynamic characteristics of 46 elements, 47 base particles, 48 redox pairs, 551 particles in solution, and 624 solid phases. The Eh–pH diagrams of the Zn–Se–H₂O and Cu–Se–H₂O systems were plotted for the average contents of these elements in underground water in oxidation zones of sulfide deposits.  相似文献