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21.
Based on observations of mesopause emissions, namely, emissions of hydroxyl (band (6-2)) and molecular oxygen (band (0-1)
of the atmospheric system), their systematic nighttime and seasonal variations are determined at Zvenigorod Observatory in
2000–2008. It is shown that the intensity of hydroxyl emission decreases during the entire night or first half-night, probably
due to the influence of the chemical sink of atomic oxygen on the nighttime behavior of hydroxyl emission. The nighttime behavior
of the intensity of molecular oxygen emission is explained by the action of atmospheric tides. The seasonal behavior of emissions
is characterized by two minima, in April–May and December; it is caused by the annual behavior of the atomic oxygen content,
temperature, and atmospheric density in the emitting layer. Based on the emission data, we determined the seasonal variations
of atomic oxygen at heights of ∼87 km (maximum of hydroxyl emission) and ∼95 km (maximum of molecular oxygen emission). 相似文献
22.
The role of normal atmospheric modes in the beginning and development of sudden stratospheric warming (SSW) events is studied on the basis of calculations with the use of the general circulation model of the middle and upper atmosphere. The analysis of the effect of a phase of quasi-biennial oscillations on the dynamics of the extratropical stratosphere has shown that the conditions for SSW commencement are more favorable and the SSW events are more intense during the easterly phase of these oscillations as compared to the westerly phase. The conclusion has been drawn that fundamental normal atmospheric modes can be recorded in the temperature field at mesopause altitudes during ground-based optical measurements. 相似文献
23.
A. I. Grabezhev N. N. Pertsev A. E. Zadov S. V. Pribavkin V. V. Murzin 《Petrology》2007,15(5):514-522
The body of hydroxylellestadite metasomatic rock penetrated by a borehole drilled at the Gumeshevsk deposit at depths of 530–534 m includes a thin interval of younger lower temperature tobermorite-plombierite metasomatic rock with subordinate amounts of Ca-Si gel, tacherenite, cubic lime, and thaumasite. Hydroxylellestadite has never before been found in calc skarns. The hydroxylellestadite metasomatic rock is cut by gypsum and fukalite veinlets, and the tobermorite-plombierite metasomatic rock is intersected by thaumasite veinlets. The pristine rock of the metasomatics was marble, and the metasomatic rock replaced andradite-bearing wollastonite skarn (with wollastonite replaced by foshagite). The ore minerals (chalcopyrite, valleriite, sphalerite, and others) were formed after the hydroxylellestadite metasomatite but most probably before the tobermorite-plombierite metasomatic rock and the veinlets of calcic minerals. The metasomatic rock was produced at significant variations in the oxygen, sulfur, and carbon dioxide fugacities. The composition of the hydroxylellestadite is, according to its microprobe analysis, as follows (wt %): SiO2 17.10, TiO2 0.01, Al2O3 0.02, FeO 0.20, MnO 0.00, MgO 0.04, CaO 55.40, Na2O 0.14, K2O 0.09, P2O5 0.12, CO2 1.90 (chemical analysis), SO3 21.60, F 0.16, Cl 0.14, total 96.92. The plombierite (SiO2 43.8–44.1 wt %, CaO 30.5–31.1 wt %) in the metasomatic rock notably differs from rare plombierite (SiO2 48.18 wt %, CaO 39.19 wt %) contained in the veinlets of thaumasite (SiO2 12.70 wt %, CaO 30.69 wt %, SO3 17.78 wt %). 相似文献
24.
Skolotnev S. G. Sanfilippo A. Peyve A. A. Nestola Y. Sokolov S. Yu. Petracchini L. Dobrolybova K. O. Basch V. Pertsev A. N. Ferrando C. Ivanenko A. N. Sani C. Razumovskii A. A. Muccini F. Bich A. S. Palmiotto C. Brusilovsky Y. V. Bonatti E. Sholukhov K. N. Cuffaro M. Veklich I. A. Ligi M. Dobrolybov V. N. 《Doklady Earth Sciences》2021,497(1):191-194
Doklady Earth Sciences - The geological and geophysical data obtained during the 50th cruise of R/V Akademik Nikolaj Strakhov on the Charlie Gibbs megatransform system structure... 相似文献
25.
Sholukhov K. N. Prokofiev V. Yu. Solovova I. P. Pertsev A. N. Aranovich L. Ya. Borisovsky S. E. Bortnikov N. S. 《Doklady Earth Sciences》2021,500(2):838-841
Doklady Earth Sciences - Despite the local occurrence of silicic magmatism during the formation of the oceanic crust, the nature of felsic granitoid veins (“oceanic plagiogranite”)... 相似文献
26.
Ivanova E. V. Skolotnev S. G. Borisov D. G. Demidov A. N. Bich A. S. Gippius F. N. Gryaznova A. S. Dobroliubova K. O. Zinger T. F. Korshunov D. M. Levchenko O. V. Mashura V. V. Muccini F. Nemchenko N. V. Peyve A. A. Pertsev A. N. Sani K. Sanfilippo A. Simagin N. V. Sokolov S. Yu. Ferrando C. Chamov N. P. Shakhovskoy I. B. Sholukhov K. N. 《Oceanology》2020,60(3):424-426
Oceanology - Herein we provide information on the integrated geological, geophysical, sedimentological, paleoceanographic, hydrophysical and biological investigations in the Central Atlantic during... 相似文献
27.
A. N. Pertsev N. S. Bortnikov L. Ya. Aranovich E. A. Vlasov V. E. Beltenev V. N. Ivanov S. G. Simakin 《Petrology》2009,17(2):124-137
Peridotites (diopside-bearing harzburgites) found at 13°N of the Mid-Atlantic Ridge fall into two compositional groups. Peridotites P1 are plagioclase-free rocks with minerals of uniform composition and Capyroxene strongly depleted in highly incompatible elements. Peridotites P2 bear evidence of interaction with basic melt: mafic veinlets; wide variations in mineral composition; enrichment of minerals in highly incompatible elements (Na, Zr, and LREE); enrichment of minerals in moderately incompatible elements (Ti, Y, and HREE) from P1 level to abundances 4–10 times higher toward the contacts with mafic aggregates; and exotic mineral assemblages Cr-spinel + rutile and Cr-spinel + ilmenite in peridotite and pentlandite + rutile in mafic veinlets. Anomalous incompatible-element enrichment of minerals from peridotites P2 occurred at the spinel-plagioclase facies boundary, which corresponds to a pressure of about 0.8–0.9 GPa. The temperature and oxygen fugacity were estimated from spinel-orthopyroxene-olivine equilibria. Peridotites P1 with an uniform mineral composition record the temperature of the last complete recrystallization at 940–1050°C and FMQ buffer oxygen fugacity within the calculation error. In peridotites P2, local assemblages have different compositions of coexisting minerals, which reflects repeated partial recrystallization during heating to magmatic temperatures (above 1200°C) and subsequent reequilibration at temperatures decreasing to 910°C and an oxygen fugacity significantly higher than FMQ buffer (Δlog $ f_{O_2 } Peridotites (diopside-bearing harzburgites) found at 13°N of the Mid-Atlantic Ridge fall into two compositional groups. Peridotites
P1 are plagioclase-free rocks with minerals of uniform composition and Capyroxene strongly depleted in highly incompatible
elements. Peridotites P2 bear evidence of interaction with basic melt: mafic veinlets; wide variations in mineral composition;
enrichment of minerals in highly incompatible elements (Na, Zr, and LREE); enrichment of minerals in moderately incompatible
elements (Ti, Y, and HREE) from P1 level to abundances 4–10 times higher toward the contacts with mafic aggregates; and exotic
mineral assemblages Cr-spinel + rutile and Cr-spinel + ilmenite in peridotite and pentlandite + rutile in mafic veinlets.
Anomalous incompatible-element enrichment of minerals from peridotites P2 occurred at the spinel-plagioclase facies boundary,
which corresponds to a pressure of about 0.8–0.9 GPa. The temperature and oxygen fugacity were estimated from spinel-orthopyroxene-olivine
equilibria. Peridotites P1 with an uniform mineral composition record the temperature of the last complete recrystallization
at 940–1050°C and FMQ buffer oxygen fugacity within the calculation error. In peridotites P2, local assemblages have different
compositions of coexisting minerals, which reflects repeated partial recrystallization during heating to magmatic temperatures
(above 1200°C) and subsequent reequilibration at temperatures decreasing to 910°C and an oxygen fugacity significantly higher
than FMQ buffer (Δlog = 1.3–1.9). Mafic veins are considered to be a crystallization product from basic melt enriched in Mg and Ni via interaction
with peridotite. The geochemical type of the melt reconstructed by the equilibrium with Ca-pyroxene is defined as T-MORB:
(La/Sm)N ≈ 1.6 and (Ce/Yb)N ≈ 2.3, which is well consistent with compositional variations of modern basaltic lavas in this segment of Mid-Atlantic Ridge,
including new data on quenched basaltic glasses.
Original Russian Text ? A.N. Pertsev, N.S. Bortnikov, L.Ya. Aranovich, E.A. Vlasov, V.E. Beltenev, V.N. Ivanov, S.G. Simakin,
2009, published in Petrologiya, 2009, Vol. 17, No. 2, pp. 139–153. 相似文献
28.
A. E. Zadov V. M. Gazeev N. N. Pertsev A. G. Gurbanov E. R. Gobechiya N. A. Yamnova N. V. Chukanov 《Geology of Ore Deposits》2009,51(8):741-749
Calcioolivine has been included into the MDI mineral database in the list of grandfathered minerals. Its history, together
with related artificial compounds, is extremely complex: various minerals and compounds received this name, including natural
orthorhombic Ca orthosilicate. In this paper, the crystal structure and properties of natural calcioolivine are described
for the first time. The new mineral has been found at Mt. Lakargi, Upper Chegem Plateau, the northern Caucasus, Kabarda-Balkaria
Republic, Russia. It has been identified in skarnified, primary carbonate xenoliths entrained by middle to late Pliocene silicic
ignimbrites of the Upper Chegem caldera. These xenoliths of a few centimeters to a few meters in size are located close to
the volcanic vent. Calcioolivine rims relics of larnite and occurs as relict grains among crystals of spurrite, rondorfite,
wadalite or secondary hillebrandite, afwillite, thaumasite, and ettringite. Hillebrandite is the major product of alteration
of calcioolivine; larnite is relatively more resistant to low-temperature alteration. Spurrite, larnite, tilleyite, kilchoanite,
cuspidine, wadalite, rondorfite, reinhardbraunsite, lakargiite (CaZrO3), members of ellestadite series, afwillite, ettringite, katoite, and thaumasite are associated minerals. It is inferred that
calcioolivine has been produced as a result of interaction of host carbonate rocks in xenoliths with volcanic lava and gases
during eruption. The name calcioolivine was approved by the Commission on New Minerals and Mineral Names, International Mineralogical Association, September 6, 2007
(no. 07-B). 相似文献
29.
30.
A. A. Peyve S. G. Skolotnev M. Ligi N. N. Turko E. Bonatti S. Yu. Kolodyazhnyi N. P. Chamov N. V. Tsukanov Yu. E. Baramykov A. E. Eskin N. Grindlay J. G. Sclater D. Brunelly A. N. Pertsev A. Cipriani G. Bortoluzzi R. Mercuri E. Paganelli F. Muccini Ch. Takeuchi F. Zaffagnini K. O. Dobrolyubova 《Doklady Earth Sciences》2007,416(1):991-994