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1.
The main features of upper atmosphere dynamics as an important part of upper atmosphere climatology are presented. The dynamics
of the mesosphere and lower thermosphere (MLT) are of special interest. The results are based on the long series of investigations
in East Siberia and data from a world-wide network of observatories. We present the regional climatic norms for the prevailing
wind and semi-diurnal tide and the main features of the quasi-periodic structure of the wind field. The non-zonality of MLT
dynamics is demonstrated as well as regional differences in the response of the wind field to stratospheric disturbances,
solar activity variations and geomagnetic storms. 相似文献
2.
This paper considers volcanogenic exhalation mineralization using data from 35 years of observation of fumarole activity during an earlier phase of the posteruptive activity of the Second Cone, which is one of the New Tolbachik volcanoes that were formed during the eruption at the North Vent of the Great Tolbachik Fissure Eruption (Kamchatka, 1975–1976). We describe the main types of mineral associations, identify the key mineral species and the secondary and accessory minerals, as well as the sequence of mineral generation. We provide a summary of minerals and compounds that have been identified in ejecta of fumaroles on the Second Cone. 相似文献
3.
Sergey V. Krivovichev Stanislav K. Filatov Lidiya P. Vergasova 《Mineralogy and Petrology》2013,107(2):235-242
The crystal structure of ilinskite, NaCu5O2(SeO3)2Cl3, a rare copper selenite chloride from volcanic fumaroles of the Great fissure Tolbachik eruption (Kamchatka peninsula, Russia), has been solved by direct methods and refined to R 1?=?0.044 on the basis of 2720 unique observed reflections. The mineral is orthorhombic, Pnma, a?=?17.769(7), b?=?6.448(3), c?=?10.522(4) Å, V?=?1205.6(8) Å3, Z?=?4. The The CuOmCln coordination polyhedra share edges to form tetramers that have 'additional' O1 and O2 atoms as centers. The O1Cu4 and O2Cu4 tetrahedra share common Cu atoms to form [O2Cu5]6+ sheets. The SeO3 groups and Cl atoms are adjacent to the [O2Cu5]6+ sheets to form complex layers parallel to (100). The Na+ cations are located in between the layers. A review of mixed-ligand CuOmCln coordination polyhedra in minerals and inorganic compounds is given. There are in total 26 stereochemically different mixed-ligand Cu-O-Cl coordinations. 相似文献
4.
The results of a periodogramanalysis of the variations in the ionospheric parameters, measured using the vertical radio sounding
method at midlatitude Irkutsk observatory (Eastern Siberia), are presented. The 1984–1986 period of observations was used.
It has been indicated that the statistically significant oscillations with periods typical of planetary waves are present
in the variations in f
0Es, f
bEs, h′Es, f
min, f
0F2, and h′F. 相似文献
5.
The results of a periodogramanalysis of the variations in the ionospheric parameters, measured using the vertical radio sounding method at midlatitude Irkutsk observatory (Eastern Siberia), are presented. The 1984–1986 period of observations was used. It has been indicated that the statistically significant oscillations with periods typical of planetary waves are present in the variations in f 0Es, f bEs, h′Es, f min, f 0F2, and h′F.
相似文献6.
L. P. Vergasova S. V. Krivovichev S. K. Filatov S. N. Britvin P. C. Burns V. V. Anan’ev 《Geology of Ore Deposits》2007,49(7):518-521
Parageorgbokiite, β-Cu5O2(SeO3)2Cl2, has been found at the second cinder cone of the Great Fissure Tolbachik Eruption, Kamchatka Peninsula, Russia. Ralstonite, tolbachite, melanothallite, chalcocyanite, euchlorine, Fe oxides, tenorite, native gold, sophiite, Na, Ca, and Mg sulfates, cotunnite, and some copper oxoselenites are associated minerals. The estimated temperature of the mineral formation is 400–625°C. The color is green, with a vitreous luster; the streak is light green. The mineral is brittle, with the Mohs hardness ranging from 3 to 4. Cleavage is not observed. The calculated density is 4.70 g/cm3. Parageorgbokiite is biaxial (+); α = 2.05(1), β = 2.05(1), and γ = 2.08(1); 2V (meas.) is ～03, and 2V (calc.) = 0(5)°. The optical orientation is X = a; other details remain unclear. The mineral is pleochroic, from grass green on X and Y to yellowish green on Z. The empirical formula calculated on the basis of O + Cl = 10 is Cu4.91Pb0.02O1.86(ScO3)2Cl2.14. The simplified formula is Cu5O2(ScO3)2Cl2. Parageorgbokiite pertains to a new structural type of inorganic compounds. Its name points out its dimorphism with georgbokiite, which was named in honor of G.B. Bokii, the prominent Russian crystal chemist (1909–2000). 相似文献
7.
Regular measurements of the velocity and direction of the horizontal wind in the mesosphere/lower thermosphere (MLT) region
at a height of ∼95 km have been conducted since 1975 over Eastern Siberia (Badary observatory near Irkutsk), using the spaced-diversity
reception method in the LF range. The accumulated database of measurement results (for more than 20 years, from 1974 to 1996)
makes it possible to get information on the impact on wind in the MLT region from both below (stratospheric warmings) and
above (geomagnetic storms as a consequence of magnetospheric disturbances) with sufficient statistical reliability. Effects
of stratospheric warmings and strong geomagnetic storms in the prevailing wind and amplitude of the semidiurnal tide are evaluated
by the superposed epoch method. It is shown that the effects of stratospheric warmings depend on the type (intensity) of stratospheric
warming and on the phase of quasi-biennial oscillations of the wind in the equatorial stratosphere at the 30 hPa level. The
response of MLT winds to external impacts is different for the 21st and 22nd cycles of solar activity. Effects of geomagnetic
storms (A
p > 100) are manifested in the decrease in the eastward prevailing wind and increase in the semidiurnal tide amplitude. 相似文献
8.
This paper presents an empirical model for space-time distribution of the basic parameters of the general circulation of the atmosphere at ionospheric levels (E-and F-regions). The model is based on the results of a physico-statistical analysis of experimental data on the measurement of horizontal ionospheric drifts by close spaced receivers, carried out by the world network of stations in 1958–1970. This model allows an evaluation of the motion parameters at a given latitude, local time, season and the level of solar activity to be made. The limitations and shortcomings of the model are discussed, the results are compared with theoretical and semi-empirical schemes of the atmospheric general circulation, as well as with data of both rocket measurements of wind and drift measurements of plasma by the method of incoherent scatter of radio waves. The physics of the results obtained are stressed. The characteristics of the model are tested and defined using the materials af the coordinated program of drift measurements in the E-region from 8 stations of the northern hemisphere in 1971–1974. The characteristics of motions at higher latitudes and the longitudinal effect are discussed. 相似文献
9.
G. V. Vergasova E. S. Kazimirovskii N. M. Polekh J. Xiong L. Liu 《Geomagnetism and Aeronomy》2011,51(6):762-773
Results of studies of the wave structure of the critical frequencies of the ionospheric F2 layer with periods of planetary waves for two Asian stations—Irkutsk and Wuhan (China)—are presented. Estimates of the appearance
frequency, amplitudes, and the lifetime of oscillations with periods typical of planetary waves (2–25 days) are obtained.
It is shown that these characteristics depend on the season and place of observation. The appearance of joint periodicities
in the critical frequencies at both stations, as well as in the planetary index of geomagnetic activity Ap, is noted. 相似文献
10.
G. A. Karpov S. V. Krivovichev L. P. Vergasova A. P. Chernyat’eva L. P. Anikin S. V. Moskaleva S. K. Filatov 《Journal of Volcanology and Seismology》2013,7(6):362-370
Samples from the surface of lava flows discharged by the 2012–2013 Tolbachik Fissure Eruption were found to contain oxysulfates of copper, sodium, and potassium: K2Cu3O(SO4)2 (fedotovite), NaKCu2O(SO4)2, and Na3K5Cu8O4(SO4)8. The last two phases have no naturally occurring or synthetic analogues that we are aware of. They form flattened crystals of prismatic to long-prismatic habits. The crystals of Na3K5Cu8O4(SO4)8 have a chemical composition corresponding to the empirical formula Na2.22K5.47Cu8.02S8.05O36. An X-ray analysis of this compound showed that it has a monoclinic symmetry, P2/c, a = 13.909(4), b = 4.977(1), c = 23.525(6) Å, β = 90.021(5)°, V = 1628.3(7) Å3. The crystal structure was determined by direct techniques and refined to yield R 1 for 3955 reflexes//web// with F 2 > 4σF. The compound NaKCu2O(SO4)2 also belongs to the monoclinic system, P2/c, a = 14.111(4), b = 4.946(1), c = 23.673(6) Å, β = 92.052(6)°, V = 1651.1(8) Å3. The structure was determined by direct techniques to yield a tentative structural model that has been refined up to R 1 = 0.135 for 4088 reflexes with F 2 > 4σF. The crystal structure of Na3K5Cu8O4(SO4)8 is based on chains of [O2Cu4]4+ consisting of rib-coupled oxy-centered tetrahedrons of (OCu4)6+. The chains are surrounded by sulfate radicals, resulting in columns of {[O2Cu4](SO4)4}4? aligned along the b axis. The interchain space contains completely ordered positions of Na+ and K+ cations. The principle underlying the connection of NaKCu2O(SO4)2 columns in the crystal structure of {[O2Cu4](SO4)4}4? is different, in view of the relation Na:K = 1 as contrasted with 3:5 for the compound Na3K5Cu8O4(SO4)8. The presence of oxy-centered tetrahedrons in the structure of these new compounds furnishes an indirect hint at the importance of polynuclear copper-oxygen radicals with centering oxygen atoms as forms of transport of copper by volcanic gases. 相似文献