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101.
102.
S. Z. Smirnov V. G. Thomas V. S. Kamenetsky O. A. Kozmenko R. R. Large 《Petrology》2012,20(3):271-285
Consideration of the existence of hydrosilicate liquids (HSL) in nature can help in understanding the accumulation and transport of some mineral- and ore-forming components at the transition from magmas to hydrothermal fluids. We studied the experimental formation of HSL using a base system Na2O-SiO2-H2O with addition of NaF, NaCl and metallic Ta. The interaction between quartz and aqueous solution, performed at 1.5 kbar and 600°C and followed either by cooling or by quench, showed that the formation of HSL occurred when initial Na2O exceeded 2 wt %. Neither NaF nor NaCl have a significant effect on the formation of HSL. The HSL concentrates F, whereas Cl partitions into the aqueous fluid. With addition of Ta to the system, the HSL becomes metal-enriched. Natural analogs of experimental HSL can be found among ??melt/fluid?? inclusions entrapped in quartz and other minerals of miaroles in granite pegmatites and raremetal granites. The HSL is a novel medium enabling extreme concentrations of lithophile ore metals at the magmatic-hydrothermal transition. 相似文献
103.
104.
A method for determining quiet daily variations (Sq curve) in automatic mode and calculating the K index of geomagnetic activity based on wavelet packets has been proposed. The method makes it possible to reproduce the Bartels
technique and includes the separation of geomagnetic signal informative components, determination of geomagnetic field disturbances,
and the formation of quiet daily variations. The method effectiveness was proved experimentally. 相似文献
105.
The effect of sunrise in time variations in the electric field in the near-Earth atmosphere at the Kamchatka Paratunka observatory has been studied. Twenty-nine records under fair-weather conditions have been selected. It has been indicated that the estimated effect parameters—the times of the effect’s onset and field strength maximum relative to the sunrise time, as well as the ratio of the strength maximum to its value before sunrise and the effect duration—coincide with the previously published data. Thereby, the conclusion is confirmed that the sunrise effect in diurnal variations in the electric field in the near-Earth atmosphere is related to the turbulence and convection processes in the atmospheric boundary layer at a change in atmospheric temperature. 相似文献
106.
We perform spectral analysis of records of meteorological (temperature, humidity, pressure of the atmosphere) and electrical (strength of quasi-static electric field and electric conductivity of air) parameters observed simultaneously at the Paratunka observatory during the solar events of October 21–31, 2003. Also, we use simultaneous records of X-ray fluxes of solar radiation, galactic cosmic rays, and the horizontal component of the geomagnetic field. We show that the power spectra of the meteorological parameters under fine weather conditions involve oscillations with a period of thermal tidal waves (T ~ 12 and 24 h) caused by the influx of thermal radiation of the Sun. During strong solar flares and geomagnetic storm of October 29–31 with a prevailing component of T ~ 24 h, their spectra involve an additional component of T ~ 48 h (the period of planetary-scale waves). With the development of solar and geomagnetic activities, the power spectra of atmospheric electric conductivity and electric field stress involve components of both thermal tidal and planetary-scale waves, which vary highly by intensity. In the power spectra of galactic cosmic rays accompanying the strong solar flares, components with T ~ 48 h were dominant with the appearance of additional (weaker by intensity) components with T ~ 24 h. The simultaneous amplification of components with T ~ 48 h in the power spectra of electric conductivity and electric field strength provides evidence of the fact that the lower troposphere is mainly ionized by galactic cosmic rays during strong solar flares and geomagnetic storms. The specified oscillation period with T ~ 48 h in their spectra, as well as in the spectra of X-ray radiation of the sun, is apparently caused by the dynamics of solar and geomagnetic activities with this time scale. 相似文献
107.
V. Smirnov R. K. Chadha A. Ponomarev D. Srinagesh M. Potanina 《Journal of Seismology》2014,18(3):587-603
Two strong M?>?5.0 earthquakes within a span of six months occurred in a triggered seismicity environment in the Koyna–Warna region in western India in 2000. The region is experiencing continued seismicity since the last five decades indicating that this region is close to critical stresses and minor perturbations in the stresses due to reservoir loading and unloading can trigger earthquakes. In the present study we applied the technique developed for identification of prognostic anomalies for tectonic earthquakes to the Koyna–Warna catalogue prior to these two earthquakes with an aim to study the process of source preparation for triggered earthquakes. In case of tectonic earthquakes, unstable conditions in a source zone develop gradually leading to a metastable zone which shows variations in certain seismicity parameters known as prognostic anomalies. Our results indicate that the variations in seismicity parameters before the two strong earthquakes in the Koyna region have a pattern of prognostic anomalies typical of tectonic earthquakes. We conclude that initiation of failure in a metastable zone can be caused both, by external impacts, reservoir loading and unloading in our case, and internal processes of avalanche-like failure development. 相似文献
108.
Butsenko V. V. Poselov V. A. Zholondz S. M. Smirnov O. E. 《Doklady Earth Sciences》2019,488(2):1182-1185
Doklady Earth Sciences - The purpose of this work was to study the seismic attributes of the Podvodnikov Basin basement. It was found that these attributes, first of all, P-wave velocities of... 相似文献
109.
E. N. Poludetkina M. B. Smirnov N. P. Fadeeva E. V. Kozlova 《Geochemistry International》2017,55(8):726-736
Samples of carbonate and siliceous-carbonate deposits of Semiluk—Sargaev horizons of the N?NE slope of the South Tatar uplift, Volga-Ural petroliferous basin, have been studied. Specific feature of the source rocks—high concentration of compounds—anoxia testifiers in the photic layer has been identified. That is, organic matter has been deposited under the conditions of the constant presence of anoxia in the photic layer of the sedimentation basin at sufficiently high thickness of the water column contaminated with hydrogen sulfide. Since by the composition of saturated hydrocarbons the studied samples are typical for deposits of the Semiluk horizon of the central part of the Volga-Ural basin, we can assume a fairly wide prevalence of such conditions within the South-Tatar arch. Changes in the concentrations of the components—anoxia markers—show cyclical changes in output layer contaminated with hydrogen sulfide or its bioproduction within the studied time. 相似文献
110.
Based on the concept of the Wiener&–Granger causality, a seasonal trivariate analysis of directional couplings between sea surface temperature variations in tropical latitudes of the Pacific, Atlantic, and Indian Oceans has been performed. These variations are related to significant modes of regional and global climatic variability. We have analyzed time series of monthly indices of Pacific Ocean processes of the El Ni&ño/Southern Oscillation (ENSO), equatorial Atlantic mode (EAM), and Indian Ocean Dipole (IOD)&—along with its western and eastern poles for the period of 1870&–2015. A scheme of interactions between the processes under study where coupling strength estimates are presented, along with estimates of the season of its maximal value and the coupling coefficient sign, has been developed. We have found the seasonal influences of ENSO on the western and eastern poles of IOD, the eastern pole of IOD on ENSO, EAM on ENSO, and IOD on EAM to be the most significant couplings. 相似文献