Geomagnetic Storm Effects at <Emphasis Type="Italic">F</Emphasis>1 Layer Altitudes in Various Periods of Solar Activity (Irkutsk Station)     

G.?P.?KushnarenkoEmail author  O.?E.?Yakovleva  G.?M.?Kuznetsova 《Geomagnetism and Aeronomy》2018,58(2):201-206

The influence of geomagnetic disturbances on electron density Ne at F1 layer altitudes in different conditions of solar activity during the autumnal and vernal seasons of 2003–2015, according to the data from the Irkutsk digital ionospheric station (52° N, 104° Е) is examined. Variations of Ne at heights of 150–190 km during the periods of twenty medium-scale and strong geomagnetic storms have been analyzed. At these specified heights, a vernal–autumn asymmetry of geomagnetic storm effects is discovered in all periods of solar activity of 2003–2015: a considerable Ne decrease at a height of 190 km and a weaker effect at lower levels during the autumnal storms. During vernal storms, no significant Ne decrease as compared with quiet conditions was registered over the entire analyzed interval of 150?190 km.  相似文献   

CARTOGRAPHIC SUPPORT FOR REGIONAL ECOLOGICAL-GEOGRAPHIC RESEARCH     

A. G. Topchiyev  L. D. Kuznetsova  N. P. Mikhaylova  O. L. Suvorovskaya 《地理信息系统科学与遥感》2013,50(1)

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Interaction of crustal and mantle materials,sources of trace elements during the formation and evolution of Early Paleozoic Li-rich granite-pegmatite systems in southeastern Tuva     

L.G. Kuznetsova 《Russian Geology and Geophysics》2018,59(12):1660-1678

We present new data on the age, composition, and environments of formation of granites of the Kystarys complex and the associated Li-rich rare-element pegmatites of the South Sangilen pegmatite belt including the large Tastyg lithium deposit. It has been established that they formed during the Early Paleozoic collisional orogeny in the Tuva-Mongolian massif at the Cambrian-Ordovician boundary. The granites of the Kystarys complex are moderately alkaline high-K rocks and are enriched in Zr, Nb, Y, and REE; therefore, they are classified as postcollisional, transitional to within-plate (A-type). The spodumene pegmatites of the South Sangilen pegmatite belt are similar to the above granites in age and isotopic and geochemical parameters, which suggests a paragenetic relationship between these rocks. Pegmatites form several pegmatite fields within the belt, which differ in trace-element signatures. In addition to predominant Li, Cs, and Ta, specific to all spodumene pegmatites (LCT family), pegmatites of two fields have high contents of Nb, Y, REE, and Zr, which are indicator elements of NYF family pegmatites. It has been established that the formation of spodumene pegmatites with combined LCT-NYF geochemical signatures was preceded by the intrusion of dikes of monzogabbro with the geochemical characteristics of OIB and of alkali aegirine granites and by the formation of associated metasomatites enriched in Zr, Nb, Y, and REE. Based on the geological, mineralogical, and geochemical data, we substantiate the hypothesis of the formation of Li-bearing granite-pegmatite melts from a mixed source resulted from the influence of fluids of an alkaline igneous complex of mantle genesis on the crustal protolith.  相似文献   

Geochemistry of lepidolitic granitoids from the Mungutiyn Tsagaan Durulj occurrence (central Mongolia)     

L.G. Kuznetsova  A.M. Spiridonov  S.I. Dril’  Z.I. Kulikova 《Russian Geology and Geophysics》2012,53(10):1077-1089

We studied the geologic position, geodynamic setting, petrology, and geochemistry of veined lepidolitic granitoids from the Mungutiyn Tsagaan Durulj (MTD) occurrence (central Mongolia), found within the area of Mesozoic intraplate rare-metal magmatism. It has been established that their trace-element enrichment resulted from the intense effect of fluids rich in F, K, Li, Rb, Cs, Sn, Be, and W, which arrived from a deep magma chamber of rare-metal granitic melts, on leucogranites with originally weak rare-metal mineralization. Very high contents of F, rare alkali metals, Sn, Be, and W, characteristic of MTD granitoids, are close only to those in greisens of rare-metal granites and topaz-lepidolite-albitic pegmatites. The difference from the greisens in each case might be due to the features of the original rocks. The difference between the greisenized MTD leucogranites and the topaz-lepidolite-albitic pegmatites is more radical: Along with evident petrographic distinctions, it includes an evolution trend toward the albite norm decrease, not typical of Li–F igneous rocks; rock shearing and gneissosity, which must have contributed to their chemical transformation according to this trend; and stably lower contents of Nb and Ta (trace elements which usually accumulate during crystallization fractionation of F–Li granitic melts and are poorly soluble in magmatic fluids). The greisenized MTD granitoids are not only high-grade rare-metal ores of Li, Rb, F, and Sn but are also regarded as an indicator of a deep concealed pluton of rare-metal granites.  相似文献   

Ecological-Geologic Risks Related to the Development of Resource Regions     

M. I. Kuz’min  A. N. Kuznetsova 《Geography and Natural Resources》2018,39(2):95-102

The ecological functions and features of the geologic environment are investigated in terms of environmental geology. The current status of the geologic medium is characterized as a crisis, and the issues of its protection and rehabilitation are not appropriately addressed in environmental protection activity of the state and businesses. The most critical ecological-geologic risks include destruction and deformation of geologic strata, huge amounts of industrial waste, oil spills, landscape and soil degradation, air and surface water pollution, seismic and mudflow phenomena, etc. Mining operations have the greatest negative influence on the environmental parameters of the geologic medium. Inadequate attention to issues related to the present state and protection of the geologic medium leads to accidents and crises in industrial installations. Ecological-geologic hazard hotspots have emerged in areas of intense extraction and processing of mineral raw materials. On the other hand, the environmental component of active mineral resource use is neglected when formulating the prospects for a further development of resource regions. The country’s major mining companies, active participants of the world market of mineral resources, are the most proficient in sustainable mineral resource use. In recent years, Russia saw a large-scale improvement of environmental legislation. Many legal innovations focusing on the preservation of the geologic medium are scattered among different laws. The legal and financial preconditions for the ecologization of mineral resource use are examined. The state plays a key role to stimulate the sustainable mining, processing and transportation of useful minerals. It has to change significantly the system to support the geologic medium protection.  相似文献   

Cloudburst floods in mountains: State of knowledge,occurrence, factors of formation     

L. V. Kuksina  V. N. Golosov  Yu. S. Kuznetsova 《Geography and Natural Resources》2017,38(1):20-29

A detailed analysis is made of the current ideas concerning floods of a special type. We examine short-lasting torrential flash floods, one of the most widespread and hazardous natural phenomena in the world characterized by a high rate of development, and by a short duration. It is established that such floods are in a primitive stage of study, which is testified by the fact that there is no general consensus as to what should be treated as a flash flood. It is pointed out that a special term designating them is also absent in many countries. It is determined that the key formation conditions for flash floods include intense short-lasting cloudbursts, the occurrence of a river basin in mountainous regions and a small drainage area; on this basis, it is suggested that they be termed flash floods. It is shown that such floods are of the most widespread occurrence in the northern hemisphere in regions with a temperate and subtropical climate. We suggest the scheme of natural factors for formation of flash floods and their differences from debris flows and floods of other types. It is determined that the main problems of investigating the formation mechanisms and forecasting the aforementioned floods are associated with the small spatiotemporal scale of these phenomena.  相似文献   

Ozone content over the Russian Federation in the first quarter of 2017     

A. M. Zvyagintsev  N. S. Ivanova  I. N. Kuznetsova  V. A. Lapchenko 《Russian Meteorology and Hydrology》2017,42(5):353-356

The review is based on the results of the operation of the total ozone (TO) monitoring system in the CIS countries. The system is functioning in the operational regime at the Central Aerological Observatory (CAO) and uses the data from the national network equipped with M-124 filter ozonometers being under the methodological supervision of the Main Geophysical Observatory. The quality of the entire system functioning is under operational control based on the observations obtained from neighboring countries and the OMI satellite equipment (NASA, USA). Basic TO observation data are generalized for each month of the first quarter of 2017 and for the first quarter. Data on surface ozone values in the Moscow region and Crimea are also provided.  相似文献   

Normative quartz as an indicator of the mass transfer intensity during the postmagmatic alteration of the Botuobinskaya pipe kimberlites (Yakutia)     

V.B. Vasilenko  A.V. Tolstov  V.A. Minin  L.G. Kuznetsova  N.V. Surkov 《Russian Geology and Geophysics》2008,49(12):894-907

The intensity of postmagmatic processes in the Botuobinskaya pipe kimberlites was estimated from the calculated content of normative secondary quartz (Q). Several simple algorithms are proposed to calculate the Q content from chemical analyses of kimberlites. Ten groups of altered kimberlites have been recognized from the Q contents. The contents of MgO, some trace elements, and LREE in the groups, the contents of Cr and Ca of crimson garnets, the diamond contents of kimberlites, and the average weight of diamonds decrease as the Q content increases. It is shown that the negative SiO₂–MgO correlation is the most effective indicator of the postmagmatic alteration of kimberlites. As the degree of their secondary alteration increases, the kimberlites transform into an assemblage of quartz and clay minerals enriched in some trace elements and almost completely lacking REE and diamonds.  相似文献   

The fluid phase evolution during the formation of carbonatite of the Guli massif: Evidence from the isotope (C,N, Ar) data     

A. I. Buikin  A. B. Verchovsky  L. N. Kogarko  V. A. Grinenko  O. V. Kuznetsova 《Doklady Earth Sciences》2016,466(2):135-137

The first data on variations of the isotope composition and element ratios of carbon, nitrogen, and argon in carbonatites of different generations and ultrabasic rocks of the Guli massif obtained by the method of step crushing are reported. It is shown that early carbonatite differs significantly from the later ones by the concentration of highly volatile components, as well as by the isotope compositions of carbon (CO₂), argon, and hydrogen (H₂O). The data obtained allow us to conclude that the mantle component predominated in the fluid at the early stages of formation of rocks of the Guli massif, whereas the late stages of carbonatite formation were characterized by an additional fluid source, which introduced atmospheric argon, and most likely a high portion of carbon dioxide with isotopically heavy carbon.  相似文献   

Ozone content over the Russian Federation in the second quarter of 2016     

A. M. Zvyagintsev  N. S. Ivanova  I. N. Kuznetsova  V. A. Lapchenko  N. V. Tereb 《Russian Meteorology and Hydrology》2016,41(9):662-664

The review is compiled on the basis of the operation of the total ozone (TO) monitoring system in the CIS and Baltic countries that functions in the operational regime at the Central Aerological Observatory. The monitoring system uses the data from the national network equipped with M-124 filter ozonometers under methodological supervision of the Main Geophysical Observatory. The quality of the functioning of the entire system is under the operational control based on the observations obtained from the OMI satellite equipment (NASA, the United States). The basic TO observation data are generalized for each month of the second quarter of 2016 and for the quarter as a whole. The data of routine observations of surface ozone content carried out in the Moscow region and Crimea are also presented.  相似文献