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91.
The January 6, 2006, Balei earthquake as a reflection of the present tectonic activity of the east Trans-Baikal Region 总被引:1,自引:0,他引:1
Mel’nikova V. I. Radziminovich Ya. B. Gileva N. A. Radziminovich N. A. Papkova A. A. 《Doklady Earth Sciences》2011,437(2):552-556
The results of detailed studies of the January 6, 2006, Balei earthquake (K
p = 13.1, M
b = 4.7 [7]), which occurred in an almost aseismic area of the east Trans-Baikal Region, are presented. The focal mechanism
and dynamical characteristics of the focus are considered, and the structural-tectonic position of the focus is analyzed.
It is supposed that the focus of this seismic event coincides with an activated segment of the northwest-striking Balei-Darasun
fault. The maximal observed macroseismic intensity was 5–6 points by the MSK-64 scale (in the town of Baleis). The origination
of foci for the earthquake with such intensity and magnitude takes place substantially owing to subhorizontal northeastern
compression, the varied-rank block structure of the medium, and low rate values of tectonic motions; on aggregate, all these
factors promote the accumulation of stresses in the Earth’s crust. The obtained data can be useful for the purpose of assessment
in seismic danger of the region. 相似文献
92.
Rock fragments from the deepest parts of a buried hydrothermal system belonging to the Mesozoic Tethys Ocean entered as xenoliths in a Miocenic diatreme,hence brought to the surface,in the Hyblean Plateau(Sicily).Some xenoliths consist of strongly serpentinized ultramafic rocks bearing blebs of abiotic organic matter,where clusters of amorphous carbon nanoparticles,including nanodiamonds,are immersed.Such an occurrence conjures up established hypotheses that diamond surfaces are suitable catalytic platforms stimulating the assemblage of complex bio-organic molecules relevant to the emergence of life on Earth.The appearance of bio-organic molecules under primitive Earth conditions is one of the major unsolved questions on the origin of life.Here we report new micro-Raman spectra on blebs of abiotic organic matter from a selected xenolith.Diamond bands were related to hydrogenated nanocrystalline diamonds,with size of nearly 1-1.6 nm,formed from organics at low pressures and temperatures.In particular,diamond surfaces can give rise to crystalline interfacial water layers that may have played a fundamental role in the early biosphere evolution as a good medium for rapidly transporting positive charges in the form of hydrated protons.Nowadays,proton gradients in alkaline hydrothermal vents along oceanic ridges are generally viewed as key pre-biotic factors.In general,serpentinites span the entire geological record,including prebiotic times.These hydrous ultramafic rocks often display evidence of abiotic carbon species,both organic and inorganic,including nanodiamonds,being also capable to give rise to chemiosmotic processes and proton gradients necessary to the organisms,such as the"Last Universal Common Ancestor"(LUCA),in the prebiotic Earth. 相似文献
93.
94.
A. A. Konovalenko A. A. Stanislavsky E. P. Abranin V. V. Dorovsky V. N. Mel’nik M. L. Kaiser A. Lecacheux H. O. Rucker 《Solar physics》2007,245(2):345-354
Here we report a radio burst in absorption at 9?–?30 MHz observed with the UTR-2 telescope. This event occurred on 19 August 2003 about 11:16?–?11:26 UT, against solar type IV/II emission background. It is the first event where absorption was observed below 30 MHz. The absorption region, comparable with the solar radius size, traveled a long distance into the upper corona from the Sun. We show that the burst minimum corresponds to the almost full absorption of the solar radio emission up to a background level of the quiescent Sun. This supports the interpretation of the phenomenon as an absorption. The result is examined independently with the Nançay Decameter Array measurements and the Wind WAVES instrument records. 相似文献
95.
L. N. Gagarina M. Yu. Vozhdaeva L. I. Kantor I. A. Mel’nitskii N. V. Trukhanova 《Water Resources》2009,36(5):513-517
It is shown that gasolines in water can be identified by the relative concentrations of the major aromatic components that
are most stable and typical of gasolines (references components): meta- + para-ethyltoluenes, 1,3,5-trimethylbenzene, ortho-ethyltoluenes,
and 1,2,4-trimethylbenzene. Three most widespread grades of gasoline are used as an example to show that the lower detection
limit of gasoline water pollution by chromatographic analysis with dynamic concentration of sample is 0.01 mg/dm3. 相似文献
96.
An analysis of the residual-velocity field of OB associations within 3 kpc of the Sun has revealed periodic variations in the radial residual velocities along the Galactic radius vector with a typical scale length of λ = 2.0 ± 0.2 kpc and a mean amplitude of f R = 7 ± 1 km s?1. The fact that the radial residual velocities of almost all OB associations in rich stellar-gas complexes are directed toward the Galactic center suggests that the solar neighborhood under consideration is within the corotation radius. The azimuthal-velocity field exhibits a distinct periodic pattern in the 0°<l<180° region, where the mean azimuthal-velocity amplitude is f θ = 6 ± 2 km s?1. There is no periodic pattern of the azimuthal-velocity field in the 180°<l<360° region. The locations of the Cygnus arm, as well as the Perseus arm, inferred from an analysis of the radial-and azimuthal-velocity fields coincide. The periodic patterns of the residual-velocity fields of Cepheids and OB associations share many common features. 相似文献
97.
O. A. Mel’nikov 《Journal of Volcanology and Seismology》2011,5(6):409-420
Visual observations of the activities of three gas-water-lithoclast (“mud”) volcanoes in the Pugachevo group in the Makarov
District of Sakhalin Island were used to analyze the dynamics of these volcanoes. Our analysis confirmed the previous inference
that a multirank periodicity is present in the eruptions of the volcanoes, with the periodicity being comparatively frequent
and low in magnitude for the eruptions (every 1–2 years) at the Glavnyi or Central volcano and a very long but violent (every
65–70 years) at all the three volcanoes. Comparison of this periodicity with a similar periodicity observed in natural seismicity
in the adjacent, highly seismic Uglegorsk District shows that the two phenomena are relatively independent. The natural seismicity
in the form of large earthquakes is superimposed upon the gas-water-lithoclast volcanism mostly to serve as a trigger. The
high-rank periodicity of 65–70 years noted above may be related to 11–22-year cycles of solar activity. Analysis of the orohydrographic
setting in the area shows that the location of the present low-lying basin with volcanoes inside was formerly occupied by
a dome uplift with a major gas field that controlled the generation of these volcanoes; it continues to drive their activity,
causing a continued gradual subsidence or collapse of the deep basin with volcanoes, thus providing evidence of the high gas
potential in the area of study. 相似文献
98.
The upper Amur region comprises weathering crusts (waste mantle developed at copper-nickel sulfide deposits included), which
appreciably hamper the prospecting for such deposits. In order to develop their prospecting criteria, the composition of linear
weathering crusts above a nickeliferous cortlandite dike and barren pyroxenite dike, as well as in the fracture zone above
metamorphic rocks, was investigated. The chemical composition of material in the weathering crust and the mineral composition
of newly formed clay fractions and heavy concentrate were determined. It was established that weathering crust in the nickeliferous
cortlandite dike is characterized by the prevalence of fine jarosite fraction with crystobalite admixture. The heavy concentrate
samples contain jarosite along with a small amount of relict sulfides (pyrite and galena) and native gold. These criteria
can be used in the prospecting for copper-nickel sulfide mineralization in the upper Amur region and other similar regions. 相似文献
99.
100.
O. V. Mingalev G. I. Mingaleva M. N. Mel’nik V. S. Mingalev 《Geomagnetism and Aeronomy》2010,50(5):643-654
Using a mathematical modeling method, evolutions of super-small-scale irregularities of electron concentration stretched along
the geomagnetic field which could be formed in the magnetized ionospheric plasma of the F2 layer both in a natural way and at an artificial impact on it, in particular, during heating experiments, are studied. Evolution
in time of the initially formed irregularities of two types having different shape of the cross sections lateral to the magnetic
field (types of direct narrow long band and with a circular cross section) is calculated. It is found that such irregularities
during times tens of times shorter than the time of the electron free path time spread out and disappear, accomplishing thereby
periodic attenuating oscillations. The period of these oscillations can be equal to both the period of Langmuir oscillations
of electrons and the period of cyclotron oscillations of electrons depending on the irregularity type and its initial parameters. 相似文献