Scientific journal “Processes in GeoMedia” № 2 (6) 2016

Аннотации статей

 

INFLUENCE OF NONLINEARITY AND BOTTOM FRICTION ON LONG WAVES IN THE CHANNELS OF A VARIABLE СROSS-SECTION

A.Yu. Bazykina, S.F. Dotsenko

Marine Hydrophysical Institute RAS

The channel model of nonlinear long waves is used for numerical analysis of transformation of a single surface long wave, which propagates in the channel of variable cross-section. It is shown that into locally expanding channels of constant depth the wave field stays weakening, but amplification of waves takes place into locally narrowing channels. The propagation of waves in a channel with a decreasing depth of wave heights influenced by the nonlinearity increases less intensive than in the linear approximation. The wave parameters are in a good agreement with the analytical estimates. The nonlinearity results in a growth of the leading wave front steepness over time and wave breaking following after that. The distance from wave origin to the breaking decreases with growth of a wave height, when the depth and width of channel are reduced. Quadratic bottom friction results in a weakening of the waves, especially for small depths.

Keywords: wave in a fluid, the waves of finite amplitude, wave propagation in channels, the channel mathematical model, numerical solutions, nonlinear effects, energy dissipation.

pp. 97-103.

 

SOLAR ACTIVITY MANIFESTATION IN THE VARIABILITY OF SEA ICE REGIONAL DISTRIBUTION IN THE ANTARCTIC

A.E. Bukatov, A.A. Bukatov, M.V. Babiy

Marine Hydrophysical Institute RAS

The investigation of relationship between climatic evolution of regional distribution of sea ice concentration, area and sea ice edge in the Southern ocean and Wolf’s sunspot numbers is done. Research is executed with use of the correlation analysis. Antarctic areas with the most considerable reaction of sea ice concentration and its total region area on change of Wolf numbers are revealed.

Keywords: Antarctic, sea ice, sea ice concentration, sea ice area, sea ice edge, Wolf number.

pp. 104-111.

 

LABORATORY STUDY OF HORISONTAL MIXING PROCESS BETWEEN TWO RIVER PLUMES AT THE KARA SEA SHELF

D.N. Elkin, V.V. Kremenetskiy, A.G. Zatsepin

P.P. Shirshov Institute of Oceanology RAS

There is usually an extensive area of waters, desalinated by Ob and Yenisey flow, in summer and autumn in the southwestern part of the Kara Sea. The thickness of the desalinated layer is about 10 m, and its salinity is less than 25 psu. Chemical analysis shows that horizontal mixing process between the interacting Ob and Yenisei plumes in the Kara Sea is not completed even after 3-4 months after their formation. The estimates of the corresponding mixing timescale based on the laboratory results give evidence that 3-4 months are not enough for complete horizontal mixing of Ob and Yenisei river plumes.

Keywords: Kara Sea, Ob and Yenisei river plumes, horizontal mixing, laboratory study.

pp. 112-119.

 

PECULIARITIES OF THERMOMAGNETIC PROPERTIES OF BOTSVANA KIMBERLITES

V.I. Maksimochkin1, R.R. Gubaydullin2

1Department of Physics, Moscow State University

2Department of Mathematics and Natural Sciences, Sterlitamak Branch,

Bashkir State University

The paper shows the results of the study of thermoremanent magnetization of Botswana kimberlites. It was found that the distinguishing feature of thermomagnetic properties of the kimberlite pipe AK06 with high concentration of diamonds (0.22 ct/t) is the presence of the effect of self-reversal thermoremanent magnetization. In samples from the kimberlite pipe VK56 with low diamonds concentration (less than 0.01 ct/t), the effect of self-reversal thermoremanent magnetization was absent. It is shown that the self-reversal magnetization is determined by the nonmagnetic cations (Mg2+, Ti4+) concentration change from the periphery to the center of the grain in magnesian titanomagnetite, formed in the late stage of crystallization at the Cr-spinel grain boundary. The presence of magnesian titanomagnetite at the Cr-spinel grain boundary and the effect of self-reversal thermoremanent magnetization can be used for a preliminary assessment of diamonds concentration in kimberlite bodies with the presence of chrome-spinels.

Keywords: kimberlites, diamonds, Cr-spinels, magnesian titanomagnetite, thermoremanent magnetization, selfreversal thermoremanent magnetization.

pp. 120-128.

 

HORIZONTAL TURBULENT FLOWS OF HEAT AND SALT IN THE BLACK SEA ACCORDING TO THE MHI NUMERICAL MODEL

A.E. Pogrebnoi

Marine Hydrophysical Institute RAS

According to the calculation of the numerical model of MHI with discreteness of 6 hours for the period from January 1, 2007 through December 31, 2008 estimations of heat and salt horizontal fluxes were made. The analysis of the spatial variability of these flows showed that the horizontal exchange in the Black Sea has a focal character, reaching values of 0.1 g·m–2·s–1 for salt and 103 W·m–2 for heat. The values of the horizontal flows generally decrease with depth, and their maximum values are in the area of the Black Sea Rim Current. For the main pycnocline (layer below 15 m), the integral values of horizontal flows. Their highs are also confined to the Black Sea Rim Current and make 25 g·m–2·s–1 for salt and 105 W·m–2 for heat.

Keywords: turbulent exchange, heat and salt fluxes, MHI numerical model.

pp. 129-134.

 

THE DISTRIBUTION OF RADON VOLUMETRIC ACTIVITY ABOVE THE SURFACE OF THE TAMAN PENINSULA

I.S. Podymov, T.M. Podymova

Southern branch of the P.P.Shirshov Institute of oceanology RAS

The work is devoted to solving the problem of the radon mapping of the Taman peninsula as a problem of the interaction between the region’s ecosystems and population. An express method of calculating the radon volumetric activity for decay energy of secondary products is designed and implemented. The data of 3-year field investigations allowed us to plot the map of the distribution of radon volumetric activity in the coastal zone of the Azov and Black seas of the Taman Peninsula, as well as over its surface. The average values of radon volumetric activity are determined in the zones of tectonic disturbances and for the main territory of the Taman.

Keywords: Taman peninsula, radon, radon volumetric activity.

pp. 135-140.

 

MODELING AVERAGE ANNUAL VERTICAL EXCHANGE IN THE BLACK SEA COLD INTERMEDIATE LAYER

A.S. Samodurov1, V.A. Ivanov1, V.N. Belokopytov1, O.E. Kulsha2

1Marine Hydrophysical Institute RAS

2Sebastopol Branch of M.V. Lomonosov Moscow state university

On the basis of long-term hydrological observations data, a model of average annual contributions to vertical exchange of local turbulent diffusion, the lower part of the Bosporus current, as well as inflows of cooled water from different areas which penetrates at the corresponding density levels for the Black Sea cold intermediate layer is constructed in the paper. The modeling is realized in the framework of inverse stationary 1.5D problem. In consequence of initial excess of unknown functions, two models for investigated system are considered successively in selected approach: a model including the lower part of the Bosporus current and vertical diffusion with lack of the winter inflows, as well as a model which takes in consideration all above mentioned contributors to vertical exchange. In the process of adding the results of the first model equations analysis to the equations set for the second model, the vertical distributions of unknown vertical exchange functions (diffusion coefficients, advection velocities) are calculated for the layer under consideration.

Keywords: Black Sea, cold intermediate layer, vertical exchange, turbulent diffusion, advection.

pp. 141-147.

 

EXPERIMENTAL INVESTIGATION OF DEFORMATION OF ROCKS IN PLANE STRAIN AND PLANE STRESS

Yu.V. Sidorin1, K.B. Ustinov1, A.A. Sirotin1, Yu.F. Kovalenko1, V.I. Karev1, A.V. Zaitsev2, A.B. Zhuravlev1

1A. Ishlinsky Institute for Problems in Mechanics RAS

2Perm National Research Polytechnic University

A series of tests has been carried on determining deformational characteristics of rocks in plane strain and plain stress using the Triaxial Independent Loading Test System (TILTS) IPMech RAS. Cubic specimens with 40 mm edges have been loaded according to chosen piecewise linear loading trajectory (plane strain and plain stress) on each of three directions independently. The obtained curves are expected of importance for verifying various governing equations describing inelastic deformation of rocks while non-proportional triaxial loading.

Keywords: rocks, stress-strain curve, inelastic deformation, true triaxial loading, piecewise linear loading trajectory.

pp. 148-155.

 

HIGH-RESOLUTION GEOACOUSTIC SYSTEM FOR GEOLOGICAL AND ARCHAEOLOGICAL STUDY OF THE BOTTOM

A.A. Schreider, Al.A. Schreider, M.S. Klyuev, E.I. Evsenko

P.P. Shirshov Institute of Oceanology RAS

In the Laboratory of Geophysics and Tectonics of the Ocean Floor at the P.P.Shirshov Institute of Oceanology, a complex for search, identification and monitoring of objects in water, on the bottom surface and in the thickness of the unconsolidated sediments is assembled. The complex includes the low-frequency parametric bottom profiler, high-frequency sonar, GLONASS/GPS satellite navigation receiver, control unit, personal computer, software, connecting cables and the electric power device. The results of sensing the environment are digitally stored and simultaneously displayed in the form of a pseudocolor sonogram. First results of the research by the complex on the waterfront in the Moscow region show the effectiveness of the developed method of studying and are of great geological and archaeological importance, because they allow to develop previous knowledge of near-surface sediments structure and on objects of cultural heritage found in the various ponds.

Keywords: high-resolution marine geoacoustics, marine geological and archaeological investigations, shelf areas.

pp. 156-161.

 

THE FLUORESCENT QUALITY CONTROL OF PURIFICATION OF WATER POLLUTED BY OIL BASED ON SHEEP WOOL SORBENTS

T.O. Chaplina1,2, O.V. Voloshina1, E.V. Stepanova2, V.V. Fadeev1

1M.V. Lomonosov Moscow State University, Physics department

2A. Ishlinsky Institute for Problems in Mechanics RAS

The method of water purification from oil by sheep wool-based sorbent is presented in the paper alongside with the possibility of evaluation of water purification quality by measuring the fluorescence intensity of oil in water and hexane extract from it by means of the internal reference method – normalization of the oil fluorescence intensity on the intensity of the range of Raman scattering of water or hexane.

Keywords: sorption capacity, oil, sheep wool, fluorescence analysis.

pp. 162-173.