排序方式： 共有12条查询结果，搜索用时 34 毫秒
1.
The results are presented of a preliminary study that aims to validate the hypothesis about the possibility of the formation of a giant dust devil resulting from the interaction of the wind with the dust clouds initiated by the impacts of meter meteoroids on the Martian surface. The laboratory experiment allowed us to examine the dynamics in the wind field of the dust ejection, whose characteristics corresponded qualitatively to the features of a dust ejection induced by the meteoroid impact. It follows from numerical computations, which are validated to some extent by comparison with the results of laboratory simulation, that the wind flowing around a dust column results in a generation of vertical eddy structures. The interaction of these structures with a convective flow, which is formed, for example, as a result of the solar heating of dusty regions, can cause the development of a dust devil. 相似文献
2.
Orlov A. M. Gorbatenko K. M. Benzik A. N. Rybakov M. O. Nosov M. A. Orlova S. Yu. 《Oceanology》2021,61(2):295-296
Oceanology - The article presents the results of hydrobiological, ichthyological, trophological, acoustic, and genetic research aboard the R/V Professor Levanidov in the Chukchi, East Siberian,... 相似文献
3.
H.-J. Götze R. El-Kelani S. Schmidt M. Rybakov M. Hassouneh H.-J. Förster J. Ebbing DESERT Group 《International Journal of Earth Sciences》2007,96(2):289-302
A 3D interpretation of the newly compiled Bouguer anomaly in the area of the “Dead Sea Rift” is presented. A high-resolution
3D model constrained with the seismic results reveals the crustal thickness and density distribution beneath the Arava/Araba
Valley (AV), the region between the Dead Sea and the Gulf of Aqaba/Elat. The Bouguer anomalies along the axial portion of
the AV, as deduced from the modelling results, are mainly caused by deep-seated sedimentary basins (D > 10 km). An inferred zone of intrusion coincides with the maximum gravity anomaly on the eastern flank of the AV. The intrusion
is displaced at different sectors along the NNW–SSE direction. The zone of maximum crustal thinning (depth 30 km) is attained
in the western sector at the Mediterranean. The southeastern plateau, on the other hand, shows by far the largest crustal
thickness of the region (38–42 km). Linked to the left lateral movement of approx. 105 km at the boundary between the African
and Arabian plate, and constrained with recent seismic data, a small asymmetric topography of the Moho beneath the Dead Sea
Transform (DST) was modelled. The thickness and density of the crust suggest that the AV is underlain by continental crust.
The deep basins, the relatively large intrusion and the asymmetric topography of the Moho lead to the conclusion that a small-scale
asthenospheric upwelling could be responsible for the thinning of the crust and subsequent creation of the Dead Sea basin
during the left lateral movement. A clear segmentation along the strike of the DST was obtained by curvature analysis: the
northern part in the neighbourhood of the Dead Sea is characterised by high curvature of the residual gravity field. Flexural
rigidity calculations result in very low values of effective elastic lithospheric thickness (t
e < 5 km). This points to decoupling of crust in the Dead Sea area. In the central, AV the curvature is less pronounced and
t
e increases to approximately 10 km. Curvature is high again in the southernmost part near the Aqaba region. Solutions of Euler
deconvolution were visualised together with modelled density bodies and fit very well into the density model structures.
An erratum to this article can be found at 相似文献
4.
Gavrilov B. G. Ermak V. M. Lyakhov A. N. Poklad Yu. V. Rybakov V. A. Ryakhovsky I. A. 《Geomagnetism and Aeronomy》2020,60(6):747-753
Geomagnetism and Aeronomy - The paper presents the results of the reconstruction of the effective height h' and the slope of the profile β of the electron concentration in the D layer of... 相似文献
5.
Recently observed features in the subsurface geology of the Haifa Bay area (northern Israel) have been evaluated using 3-D forward gravity and magnetic modeling and inversion schemes. The interpretation is based on updated petrophysical data of the Jurassic, Cretaceous and Tertiary sedimentary layers and volcanics. It has been shown that the Bouguer gravity anomalies correspond mainly to thickness variations in the Senonian to Tertiary sediments. The gravity effect of these sediments was calculated using their actual densities and structural setting as interpreted from seismic reflection data. This effect was removed from the Bouguer gravity in order to study the pre-Senonian geological structures. The pattern of residual gravity anomalies (named “stripped gravity”) is essentially different from the pattern of the Bouguer gravity. The prominent Carmel gravity high, clearly seen on the Bouguer gravity map, completely vanishes on the “stripped” gravity map. That suggests that this relatively positive anomaly is caused by the considerable thickness of the low-density young sediments in the surrounding areas and does not correspond to high-density magmatic rocks or crystalline basement uplift as previously suggested. The average densities of the Jurassic and Cretaceous volcanics are generally lower then those of the background sedimentary rocks. Volcanics are the main cause for magnetic anomalies onshore and offshore northern Israel. The magmatic root of the Asher volcanics is, most probably, located close to the Yagur fault. A large, deep-seated gabbroic intrusion is assumed to be located under the Mediterranean abyssal plain in the NW part of the study area. The Atlit marine gravity low appears to be caused by a thick Mesozoic and Tertiary sedimentary accumulation. The results presented should be of considerable assistance in delineating some aspects of hydrocarbon exploration in the area. 相似文献
6.
The structure, isostasy and gravity field of the Levant continental margin and the southeast Mediterranean area 总被引：1，自引：0，他引：1
Amit Segev Michael Rybakov Vladimir Lyakhovsky Avraham Hofstetter Gidon Tibor Vladimir Goldshmidt Zvi Ben Avraham 《Tectonophysics》2006,425(1-4):137-157
A 3-D layered structure of the Levant and the southeastern Mediterranean lithospheric plates was constructed using interpretations of seismic measurements and borehole data. Structural maps of three principal interfaces, elevation, top basement and the Moho, were constructed for the area studied. This area includes the African, Sinai and Arabian plates, the Herodotus and the Levant marine basins and the Nile sedimentary cone. In addition, an isopach map of the Pliocene sediments, as well as the contemporaneous amount of denuded rock units, was prepared to enable setting up the structural map of the base Pliocene sediment. Variable density distributions are suggested for the sedimentary succession in accord with its composition and compaction. The spatial density distribution in the crystalline crust was calculated by weighting the thicknesses of the lower mafic and the upper felsic crustal layers, with densities of 2.9 g/cm3 and 2.77 g/cm3, respectively. Results of the local (Airy) isostatic modeling with compensation on the Moho interface show significant deviations from the local isostasy and require variable density distribution in the upper mantle. Moving the compensation level to the base of the lithosphere ( 100 km depth) and adopting density variations in the mantle lithosphere yielded isostatic compensation (± 200 m) over most of the area studied. The spatial pattern obtained of a density distribution with a range of ± 0.05 g/cm3 is supported by a regional heat flux. Simulations of the flexure (Vening Meinesz) isostasy related to the Pliocene to Recent sedimentary loading and unloading revealed concentric oscillatory negative and positive anomalies mostly related to the Nile sedimentary cone. Such anomalies may explain the rapid subsidence in the Levant Basin and the arching in central Israel, northern Sinai and Egypt during Pliocene–Recent times. Comparison between the observed (Bouguer) gravity and the calculated gravity for the constructed 3-D lithospheric structure, which has variable density distributions, provided a good match and an independent constraint for the large-scale structure suggested and confirmed an oceanic nature for the Levant Basin lithosphere. 相似文献
7.
R Srinivasan K Naha Y J Bhaskar Rao A B Vrevsky S I Rybakov A I Golubev M Efimov 《Journal of Earth System Science》1993,102(4):567-585
The middle to late Archaean rocks of Kola and Karelia in the eastern Baltic shield consist of the Infracomplex overlain by the Saamian complex, and the Lopian greenstone belts. The Infracomplex which forms the basement is a polymigmatite, parts of which are at least 3100 Ma old. The Saamian in the central Belomorian region comprises granite gneiss, amphibolite, garnet-kyanite gneiss and high alumina gneisses which belong to the Keret, Hetolombina and Chupa suites. The Lopian greenstone belts ranging in age from 3000 to 2700 Ma are composed of peridotitic, pyroxenitic and basaltic komatiites, tholeiitic basalts, andesites, dacites and rhyolites, together with tuffs, graywackes and iron formations. Whereas there is a dominance of volcanic over sedimentary rocks in the greenstone belts of the Baltic shield, a significant proportion of detrital and chemogenic sedimentary rocks characterizes the Dharwar succession of approximately the same time span in the southern Indian shield. Association of mature and immature detrital sedimentary rocks with bimodal volcanic assemblages points to a back-arc setting for the Dharwar belts. This contrasts with the association of immature sediments with calc-alkaline volcanic rocks in the greenstone belts of the eastern Baltic shield, suggesting an island arc environment there. 相似文献
8.
The measurements of the critical frequencies of the ionospheric F2 layer based on vertical radiosounding, which was performed with a CADI digital ionosonde at the Voeykovo magnetic–ionospheric observatory in February 2013, have been considered. The observations have been compared with the upper atmosphere numerical model (UAM) data for three days that differ in the amplitude and the character of solar and magnetic activity and correspond to quiet and moderately disturbed states of the ionosphere. The work was performed in order to improve the methods for determining the ionospheric state by vertical sounding ionograms. The time variations in the F2 layer critical frequency, electric field vector zonal component, and thermospheric wind velocity meridional component have been analyzed. Calculations were performed with three UAM variants. The UAM version providing the best agreement with the CADI ionosonde data was the version in which the neutral temperature, neutral composition, and pressure gradients are calculated according to the MSIS empirical model and the horizontal neutral wind velocity is determined by the equation of motion with pressure gradients from MSIS. The calculated values corresponded to the measurements, except those for the evening, because the electron density at the ionospheric F2 layer maximum depends more strongly on electric fields and thermospheric wind velocities during this period. Thus, the indicated UAM version with the above limitations can be used to determine the state of the subauroral ionosphere. 相似文献
9.
G. V. Givishvili L. N. Leshchenko V. V. Alpatov S. A. Grigor’eva S. V. Zhuravlev V. D. Kuznetsov O. A. Kusonskii V. B. Lapshin M. V. Rybakov 《Solar System Research》2013,47(4):280-287
The data, obtained for the first time, permit the conclusion to be drawn, with a high degree of probability, that large meteors similar to the Chelyabinsk meteor, while entering the Earth’s atmosphere, are able to cause perturbations within the whole ionospheric stratum, rather than only at the sporadic Es layer altitudes, as previously thought. 相似文献
10.
V. F. Fateev A. I. Zharikov V. P. Sysoev E. A. Rybakov F. R. Smirnov 《Doklady Earth Sciences》2017,472(1):91-94
The results of the Russia’s first ground-based experiment for determination of the difference in the Earth’s gravitational potentials on the basis of the measurement of the gravitational effect of the time delay with the help of a high-stability transportable atomic clock are provided. The reference atomic clock was placed in Moscow oblast, and a transportable quantum clock with an instability of 3 × 10–15 was placed in the Caucasus Mountains, with a difference in height of the clocks of 1804 m. The measured difference in the gravitational potentials between the positions of the two quantum clocks was (182.0 ± 3.1)102m2s-2 at a relative measurement error of no more than 1.7%. 相似文献