Oxygen isotopic composition and nature of fluid during the formation of high-Al corundum-bearing rocks of Mt. Dyadina,northern Karelia     

D. P. Krylov  V. A. Glebovitsky 《Doklady Earth Sciences》2007,413(1):210-212

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Metamorphic evolution of ultrahigh-temperature Fe- and Al-rich granulites in the south Yenisei Ridge and tectonic implications     

I. I. Likhanov  A. D. Nozhkin  V. V. Reverdatto  A. A. Krylov  P. S. Kozlov  V. V. Khiller 《Petrology》2016,24(4):392-408

This study provides the first evidence for the occurrence of ultrahigh-temperature (UHT) granulite-facies metamorphism in the Yenisei Ridge (Angara–Kan block). UHT metamorphism is documented in Fe-Al-rich metapelites on the basis of the garnet–hypersthene–sillimanite–cordierite–plagioclase–biotite–spinel–quartz–K-feldspar assemblage. Microtextural relationships and compositional data for paragneisses of the Kan complex attest to three distinct metamorphic episodes: (M1) pre-peak prograde (820?900°C/5.5–7 kbar), (M2) peak UHT (920–1000°C/7–9 kbar), and (M3) post-peak retrograde (770?900°C/5.5–7.5 kbar). The observed counterclockwise P–T evolution at a high geothermal gradient (dT/dP = 100–200°C/kbar) suggests that UHT metamorphic assemblages were formed in an overall extensional tectonic setting accompanied by underplating of mantle-derived mafic magmas, which may be sourced from ~1750 Ma giant radiating dike swarms linked to the Vilyuy mantle plume as part of the Trans-Siberian LIP. The broad synchroneity of UHT metamorphism (1744 ± 26 Ma; monazite–zircon isochron age) and rift-related endogenic activity in the region can provide an additional line of evidence for the two-stage evolution of granulite-facies metamorphism in the Angara–Kan block. The Aldan–Stanovoy, Anabar, and Baikal basement inliers of high-grade metamorphic rocks within the Siberian craton record two Paleoproterozoic peaks (1.9 and 1.75 Ga) of granulite-facies metamorphism. The synchronous sequence of tectonothermal events at the periphery of the large Precambrian Laurentian, Baltica, and Siberian cratons provide convincing evidence for their spatial proximity over a wide time interval, which is consistent with the most recent paleomagnetic reconstructions of the Proterozoic supercontinent Nuna.  相似文献   

Calculation of Stable Isotope (O,C, Ca) Fractionation Factors for Apatite     

Krylov  D. P.  Kuznetsov  A. B.  Akimova  E. Yu. 《Doklady Earth Sciences》2018,482(2):1354-1356

The isotope fractionation β-factors have been determined for hydroxyapatite, fluorapatite, and carbon–apatite upon ¹⁸O/¹⁶O, ¹³C/¹²C, and ⁴⁴Ca/⁴⁰Ca substitutions depending on the temperature. Calculations were performed based on density functional theory (DFT). The results are expressed in terms of cubic polynomials against x = 10⁶/T(K)² and can be utilized as geothermometers if combined with β-factors of the coexisting phases. The new values of β-factors completely supersede the conventional semi-empirical (estimated by the method of increments) calibrations of isotopic equilibria involving apatite.

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New Data on Seismotectonics of the Laptev Sea from Observations by Ocean Bottom Seismographs     

Krylov  A. A.  Lobkovsky  L. I.  Rukavishnikova  D. D.  Baranov  B. V.  Kovachev  S. A.  Dozorova  K. A.  Tsukanov  N. V.  Semiletov  I. P. 《Doklady Earth Sciences》2022,507(1):936-940

Doklady Earth Sciences - The results of new local seismic observations in the Laptev Sea obtained using ocean bottom seismographs were compared with actual data from global and regional earthquake...  相似文献   

The First Petrological Evidence for Subduction at the Western Margin of the Siberian Craton     

Likhanov  I. I.  Kozlov  P. S.  Savko  K. A.  Zinoviev  S. V.  Krylov  A. A. 《Doklady Earth Sciences》2019,484(1):79-83

Doklady Earth Sciences - The discovery of relics of glaucophane schist in high-pressure tectonites of the suture zone of Yenisei Ridge has provided evidence for a Cordillera-type convergent...  相似文献   

Effect of a Shift in Diurnal Geomagnetic Variation on the Activity and Sensitivity of Digestive Glycosidases in Roach Underyearlings to Heavy Metals     

Golovanova  I. L.  Filippov  A. A.  Chebotareva  Yu. V.  Urvantseva  G. A.  Krylov  V. V. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(11):1623-1628

Izvestiya, Atmospheric and Oceanic Physics - The effect of temporal shifts in diurnal geomagnetic variation with 6- and 12-h intervals relative to the day–night cycle on the activity of...  相似文献   

Isotope Fractionation and the Pressure Effect on 18O/16O in Kyanite-Sillimanite-Andalusite Polymorphs (Al2SiO5): Ab-Initio Modelling     

Krylov  D. P.  Kuznetsov  A. B.  Gavrilova  A. A. 《Doklady Earth Sciences》2020,491(2):235-237

Doklady Earth Sciences - The β-factor dependences on temperature upon 18O/16O substitution have been originally deduced in andalusite, sillimanite and kyanite accounting for pressure effect:...  相似文献   

Petrogenesis,U–Pb Age,and Lu–Hf Systematics of Rocks of the Garevka Complex (Northern Yenisei Ridge): Evidence of the Grenville Events at the Western Margin of the Siberian Craton     

Likhanov  I. I.  Reverdatto  V. V.  Kozlov  P. S.  Savko  K. A.  Krylov  A. A. 《Doklady Earth Sciences》2022,507(2):1071-1079

Doklady Earth Sciences - It is established for the first time that biotite plagiogneisses from the Garevka metamorphic complex of the North Yenisei Ridge have geochemical characteristics of C-type...  相似文献   

Analysis of accumulation factor of cesium 137 in bottom sediments of surface water bodies     

A. L. Krylov  A. V. Nosov  V. P. Kiselev 《Russian Meteorology and Hydrology》2011,36(1):33-39

The accumulation factor of radionuclides in river and water body bottom sediments K is an integral magnitude and depends on many parameters. With a two-compartment migration model (water-bottom sediments) an analytical relation is established for the conditions of a steady-state process of radioactive transfer for calculating K depending on the known parameters of radionuclide migration in the aquatic environment. With a reference to cesium 137 the calculated factor value is found for silty sediments in rivers and water bodies under characteristic summertime parameters of migration. The numerical analysis showed that the coefficient of radionuclide distribution in the water-suspension system and turbidity influence mostly the K value for cesium 137. For the practical use of this coefficient, a scheme of its correction is suggested depending on turbidity. An example of its practical use for calculating cesium 137 in water is considered. The calculated and measured volumetric activity values are intercompared.  相似文献   

Neoproterozoic and Lower Cambrian rock complexes in central areas of the Siberian Craton: Their structure and petroleum prospects     

S. V. Frolov  E. E. Karnyushina  N. I. Korobov  N. P. Fadeeva  G. G. Akhmanov  O. V. Krylov 《Moscow University Geology Bulletin》2008,63(6):386-392

The paper summarizes data on the geology, lithology, and geochemistry of petroliferous Riphean, Vendian, and Lower Cambrian rocks in the central parts of the Siberian Craton. The petrological-geological properties of these sediments have been assessed based on results of paleogeographic analysis of these rocks, discrimination of oil reservoirs and oil-source successions, determination of secondary alterations of the rocks, and sources of oil generation and regional migration of hydrocarbons into various traps in zones of possible oiland-gas accumulation.  相似文献