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21.
V. K. Milyukov A. P. Mironov A. N. Ovsyuchenko E. A. Rogozhin A. V. Gorbatikov V. N. Drobyshev Kh. M. Khubaev A. V. Nikolaev 《Doklady Earth Sciences》2018,481(1):879-882
The results of the first GPS measurements along the geophysical profile that intersects all major geological structures of the Osetiya region of the Greater Caucasus are presented. The results of the measurements are interpreted in comparison with those of neotectonic studies and data on the deep structure. 相似文献
22.
K. M. Mirzoev A. V. Nikolaev A. A. Lukk S. L. Yunga 《Izvestiya Physics of the Solid Earth》2009,45(10):885-904
Natural and anthropogenic impacts on seismicity are considered. Taking into account the importance of the discussed problem,
the authors propose to open the discussion on the questions considered. In this connection a wide circle of known experimental
data is considered, which are indicative of the possibility in principle of active impact on the seismogenic medium for the
smooth relieving of accumulated tectonic stresses in the Earth’ s crust. The reasoning is presented of one of the promising
ways of the smooth controlled relaxation of the accumulated tectonic stresses in the Earth’s crust at the places of the probable
onset of strong earthquakes due to a considerable increase in the plastic slips, which facilitate the decrease of the number
and energy of earthquakes. The approach proposed is based on the results of the works on the excited seismicity, obtained
in different regions of the Earth. Special attention is given to the most detailed long-term investigations of the excited
seismicity in the region of the reservoir of the Nurek hydroelectric station in Tadzhikistan and in the neighborhood of the
actively mined Romashkinskoe oil deposit in the Republic of Tatarstan. The results of the laboratory investigations of the
behavior of samples made of materials of crystalline and amorphous structures under the action of pressure and vibration are
invoked for the substantiation of the physical nature of the observed effects. For the reduction of seismic hazard, it is
proposed to use vibration actions and water injection in the bore holes at the places of the expected seismic catastrophes
in a time mode matched with the tidal motions of the Earth. 相似文献
23.
Modifications of integral bubble and jet models including the pressure force are proposed. Exact solutions are found for the modified model of a stationary convective jet from a point source of buoyancy and momentum. The exact solutions are compared against analytical solutions of the integral models for a stationary jet that are based on the approximation of the vertical boundary layer. It is found that the modified integral models of convective jets retain the power-law dependences on the altitude for the vertical velocity and buoyancy obtained in classical models. For a buoyant jet in a neutrally stratified atmosphere, the inclusion of the pressure force increases the amplitude of buoyancy and decreases the amplitude of vertical velocity. The total amplitude change is about 10%. It is shown that in this model there is a dynamic invariant expressing the law of a uniform distribution of the potential and kinetic energy along the jet axis. For a spontaneous jet rising in an unstably stratified atmosphere, the inclusion of the pressure force retains the amplitude of buoyancy and increases the amplitude of vertical velocity by about 15%. It is shown that in the model of a spontaneous jet there is a dynamic invariant expressing the law of a uniform distribution of the available potential and kinetic energy along the jet axis. The results are of interest for the problems of anthropogenic pollution diffusion in the air and water environments and the formulation of models for statistical and stochastic ensembles of thermals in a mass-flux parameterization of turbulent moments. 相似文献
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Until now, the age of deep-water scleractinians was determined based only on rare finds of these corals in terrestrial sequences,
which constitute <10% of their known diversity. Inasmuch as most of the non-zooxanthellate coral species dwell in the ocean
beyond the shelf zone (up to the abyssal depths) and their fossil remains are missing from terrestrial sections, we propose
a new approach to the assessment of their age based on paleoecological features: the seawater temperatures in the geological
past and the habitat temperature ranges established for 53 coral species. The study confirmed our previous assumption concerning
the very young age of the deep-water fauna. 相似文献
27.
L. Genoni P. Iacumin V. Nikolaev Yu. Gribchenko A. Longinelli 《Earth and Planetary Science Letters》1998,160(3-4):587-592
58 samples of fossil mammoth and reindeer teeth and bones of various ages and coming from different locations were studied for the oxygen isotopic composition of their phosphate. Samples from Siberia have interstadial (Marine Isotope Stage 3), stadial (MIS 2), late-glacial and post-glacial ages. Russian and Ukrainian samples refer to the late-glacial and transitional (between the interstadial and glacial stages) time. The δ18O of palaeoenvironmental waters were calculated from the δ18Op obtained from fossil samples by means of the isotope equations calibrated on modern specimens of elephants and deer respectively. The δ18Ow obtained are generally lighter than those measured nowadays in the same areas and not far from those measured on ice cores of Holocene age, the isotopic differences being not greater than a few δ units. The calculated values are also in fairly good agreement with some isotopic values obtained from Siberian permafrost samples. According to the results obtained it seems that the elephant and deer equations can be reasonably used respectively in the case of fossil mammoth and deer skeletons to evaluate environmental palaeowaters. 相似文献
28.
Conclusions Our study shows the universality of the power-law spectrum with =3 in PTR in the presence of a magnetic field. This result is important to astrophysical applications because there is no doubt that magnetic fields are present in many different types of cosmic objects. This universality can be compared with the known statistical analysis of the spectra of various cosmic radio sources (Fig. 5); the most probable value is close to =3. The spread in the observed values of could be due to the escape of particles, nonuniformity, and so on, and requires further study.Moscow Institute of Engineering Physics. Translated from Astrofizika, Vol. 12, No. 1, pp. 107–120, January–March, 1976. 相似文献
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Doklady Earth Sciences - 相似文献
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Tsvetkov Yu. P. Kuznetsov V. D. Golovkov V. P. Brekhov O. M. Pelle V. A. Krapivnyi A. V. Nikolaev N. S. 《Doklady Earth Sciences》2011,436(1):117-121
The solution to the problem of extraction of the anomaly Earth’s magnetic field (EMF) from stratospheric balloon magnetic
surveys with the help of global analytical models of the normal EMF is proposed. In the problem solution, errors for the analytical
models of the normal EMF and its secular variation at a set moment of time are assessed; the found error is introduced as
a correction to the extracted anomaly EMF. The error of the model is determined in the places where significant magnetic anomalies
are absent. In this case, the error of the model corresponds to deviations of the normal EMF components, synthesized by coefficients
of analytical models, and to deviations of the EMF secular variations from the measured values at quite a low value of the
variable EMF or one being taken into account. These places are determined when carrying out additional measurements in vertical
gradients of the EMF with the use of scalar magnetometers at the gauge length of 6 km. It has been shown that the found places
can be considered as nonanomaly, if the difference of values of the anomaly EMF at the gauge length of 6 km does not exceed
1.5 nT within the profile’s portion of about 100 km in length. An experiment in nature has revealed that errors for the IGRF-2005
and IGRF-2010 models, corrected for secular variation of the EMF, can reach 200 and 140 nT, respectively, within the limits
of the territory where the Kama-Emba magnetic anomaly is located; these errors are determined by the considered causes. Comparison
of aerostatic profiles of magnetic anomalies with data on the anomaly EMF, derived from the maps, has shown that the realizations
derived from the maps contain overestimated negative values of the anomaly EMF, because they reflect processes in the near-surface
layer of the Earth’s crust. This fact causes the situation when attempts to recalculate the anomaly EMF into the upper half-space
by the near-surface data still have not been successful. Only realizations derived at the altitudes comparable to the thickness
of the Earth’s crust can give an adequate model of the anomaly EMF in the circumterrestrial space and enable us to recalculate
magnetic anomalies reliably into any altitude levels. 相似文献