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   

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)

  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   

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   

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   

Microbiological Processes in the Gor'kovskoe Reservoir     

Dzyuban  A. N.  Kosolapov  D. B.  Kuznetsova  I. A. 《Water Resources》2001,28(1):42-53

The abundance of various groups of bacteria and the rate of microbiological processes of organic decay and methane cycle in the water and soils of the Gor'kovskoe Reservoir are determined, and the ecological characterization of its river reach is presented. The autochthonous and allochthonous impact on the bacterial community of the reservoir was found to be tolerable; however, some restricted areas were revealed, where the ecosystem is strongly affected by domestic and industrial wastewater, and where the abundance and activity of anaerobic methane-producing and sulfate-reducing soil bacteria increase.  相似文献   

Ozone content over the Russian federation territory in 2006     

A. M. Zvyagintsev  N. S. Ivanova  G. M. Krutchenitskii  I. N. Kuznetsova  E. A. Lezina 《Russian Meteorology and Hydrology》2007,32(2):142-146

The review is compiled based on the results of the operation of the Total Ozone (TO) Monitoring System in the CIS and Baltic countries, functioning in the operational regime at the Central Aerological Observatory (CAO). The monitoring system used the data from the national network of filter ozonometers, type M-124, operating under the methodological control of the Main Geophysical Observatory (MGO). The quality control of the entire system is performed based on the observations with the satellite OMI (NASA) equipment. The basic results of TO observations for each month of the fourth quarter of 2006 and for a year as a whole are generalized. Results of regular surface ozone observations in the Moscow region are considered as well.  相似文献   

Magnetospheric plasma discontinuity by the geostationary version of the differential phase method during storms     

J. V. Kovalevsky  T. V. Kuznetsova 《Planetary and Space Science》1977,25(12):1145-1150

It is shown that the dynamics of the plasmapause, the plasmasphere plasma tails, the plasma sheet and the magnetosheath boundaries of the geomagnetosphere may be investigated by means of the geostationary version of the differential phase method, by which a signal transmitted from a sounding station (a geostationary satellite) and received by a response station on the Earth may be transformed, allowing the sign of the frequency shift and of the phase lag to be changed. Information on the location, the motion of the magnetospheric plasma discontinuities and the concentration drop at their boundaries may be obtained from measurements carried out on board the geostationary satellite of the phase difference of the sounding and response signals ΔΦ, the time of its increase Δt and the phase difference change rate (fast beating frequency Δƒ = ΔΦ/2π Δt). The establishment of communication between appropriately spaced ground stations and a satellite with a quasi-polar orbit allows the midlatitude plasmapause dynamics, and those of the ionosphere trough, polar cusp boundaries and of polar cap inhomogeneities to be studied. Equipment with a stability of 10⁻¹¹–10⁻¹² is needed for the most dynamical events (for ΔΦ= 10⁻⁴ tens of rad. and for Δƒ= 10⁻⁵ tens of Hz) occurring in the radio path during storms.  相似文献   

Ozone content over the Russian federation in the second quarter of 2008     

A. M. Zvyagintsev  N. S. Ivanova  G. Kakadzhanova  G. M. Kruchenitskii  I. N. Kuznetsova 《Russian Meteorology and Hydrology》2008,33(8):537-540

  相似文献   

On the Mechanisms of Variability of the Atlantic Meridional Overturning Circulation (AMOC)     

Kuznetsova  D. A.  Bashmachnikov  I. L. 《Oceanology》2021,61(6):803-814

Oceanology - In this paper we investigate the relationship between the long-term variability of the Atlantic Meridional Overturning Circulation (AMOC) and the intensity of deep convection in the...  相似文献