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We suggest a more rigorous approach to paleogeodynamic reconstructions of the Sayan-Baikal folded area proceeding from update views of the origin and evolution of island arcs and back-arc basins. Modern island arcs and attendant back-arc basins form mainly by trench rollback caused by progressive subduction of negatively buoyant thick and cold oceanic slabs. Slab stagnation upsets the dynamic equilibrium in the subduction system, which accelerates the rollback. As a result, a continental volcanic arc transforms into an island arc, with oceanic crust production in the back-arc basin behind it. As subduction progresses, the island arc and the back-arc basin may deform, and fold-thrust structures, with the involved back-arc basin and island arc complexes, may accrete to the continent (accretion and collision) without participation of large colliding blocks. When applied to the Sayan-Baikal area, the model predicts that the Riphean and Vendian-Early Paleozoic back-arc basins were more active agents in the regional geologic history than it was thought before. They were deposition areas of sedimentary and volcanosedimentary complexes and then became the scene of collision and accretion events, including folding, metamorphism, and plutonism.

We report the first data on the contents of main oxides and REE in rocks and the compositions of pyropes and almandines from the Maiskoe kimberlite body recently discovered in the Nakyn field of the Yakutian kimberlite province.

A comparative analysis of morphology and geochemistry was made for gold from the primary ores and weathering crust of the Suzdal' gold deposit, Eastern Kazakhstan. The deposit is localized in Carboniferous carbonaceous-terrigenous strata and is of gold-sulfide type. Study of gold from primary ores showed that it occurs mainly in two species: free and so-called invisible. Free gold is crystallomorphic segregations and irregular-shaped grains up to tens of microns in size; it occurs in intergrowths with sulfides, quartz, carbonate, and mica-chlorite aggregate. Most of gold particles have a fineness of 930-980

The Berezitovoe gold-polymetallic deposit is localized in the west of the Selenga-Stanovoi superterrane composed of a wide spectrum of Early and Late Precambrian igneous rocks and abundant Paleozoic and Mesozoic intrusive and volcanoplutonic associations. The ⁴⁰Ar/³⁹Ar ages determined for metasomatites bearing gold-polymetallic mineralization are as follows: garnet-quartz-muscovite-sericite-K-feldspathic metasomatites (129.7±3.2-127.3±4.4 Ma); muscovite-quartz-sericite metasomatites (132.0±2.9-131.3±2.3 Ma). According to the age and general scheme of evolution of the Early Cretaceous magmatism in the Selenga-Stanovoi superterrane, the metasomatites of the Berezitovoe deposit are nearly coeval to the intrusive rocks of the Amudzhikan complex (132-128 Ma). The revealed platinum potential of gold-polymetallic ores and metasomatites permits ranking the Berezitovoe deposit as a specific complex gold-polymetallic-platinum deposit, which considerably increases its commercial value.

We have obtained formulas to calculate the field components of an eccentric dipole (ED) with an arbitrarily directed moment from specified coordinates of the dipole center and from its moment vector. With these formulas, the model dipole position was fitted to the observed geomagnetic field, and the approximation accuracy was estimated according to the standard deviation from IGRF along the X , Y , and Z components; the fitting procedure was checked in several tests.
We computed the ED parameters (position and moment orientation) and harmonic coefficients of the ED field for 50 years using surface IGRF components, discovered some changes, and compared them with those according to the Schmidt eccentric dipole model. It was found that the nondipolar contributions to the geomagnetic field increase as the dipole field decays with time, and the dipole center drifts north- and eastward away from the Earth's gravity center.
The main contribution of the dipole part in the Gaussian spherical harmonic expansion of the geomagnetic field turned out to come from the terms with n of 1 to 5 rather than from two first terms, and the contribution of higher harmonics increases with time. Therefore, the Schmidt ED approximation based on the first eight Gauss coefficients ( n ≤ 2) must have only relative significance indicating changes of the parameters. On the other hand, world magnetic anomalies (WMA) show up already in two first Gauss terms rather than since the third term as it has been commonly assumed.

We investigated space-time lithospheric stress patterns of the Baikal rift system according to the hierarchy of earthquakes using mechanisms of 265 K _P ≥ 10 events recorded from 1950 to 1998 and seismic moments of 802 K _P ≥11 events from 1968 to 1994. The lithosphere of the region was confirmed to undergo rifting with mostly normal-slip events, while local areas of frequent strike-slip and reverse motions may record stress heterogeneity. The dominance of rifting, although being evident in the stress dynamics, is unstable, which is indicated by increase in strike-slip and reverse motions to as many as normal slip events in the latest 1980s-earliest 1990s. The lithospheric stress patterns inferred from seismic-moment data are generally consistent with those derived from the classical focal mechanism method. The suggested approach of seismic zoning according to earthquake slip geometry may provide a more reliable background for successful mitigation of seismic hazard in the region.

The mechanics of the ice cover of Lake Baikal has been studied through monitoring of its deformation and seismic effects and full-size uniaxial compression and shear tests in 2005-2007. We measured the shear strength of ice specimens and large in situ blocks (σ = 0.2-1.9 MPa) and investigated it as a function of air temperature and ice structure. Deformation was analyzed in terms of various natural controls, such as air temperature and pressure, wind, sub-ice currents, and local earthquakes. Precise strain measurements along ice cracks were used to explore the strain behavior of ice, including the cases of dynamic failure (ice shocks). Measurements by seismic station Baikal-12 were used to monitor diurnal background microseismicity variations and to record an ice quake with its magnitude ( M = 0.3-0.8; E = 10⁴-10⁵ J) comparable to a medium-size rock burst or a small earthquake. Ice quakes were studied in terms of their nucleation, dynamics, and aftereffects, as well as the strain and seismic responses of the ice, using sub-ice explosions in the latter case. The natural conditions of deformation in the elastoviscoplastic Baikal ice are similar to lithospheric processes and thus can be employed in tectonophysical modeling with scientific and practical implications for hazard mitigation.

Ungrounded horizontal loop responses at low frequencies and/or late times can be modeled in terms of an equivalent circuit with lumped elements, but a loop in a general case is a distributed system. At high frequencies and/or early times, the wire in combination with the underlying earth makes a transmission line in which current behaves according to the wave equation. Solving the equation for current turn-off is quite difficult because the primary parameters of the wire-earth system depend, in an intricate way, on earth conductivity (resistivity) and frequency (or time). In modeling the current turn-off process, the loop was simulated as a symmetrical combination of two identical transmission lines with shorted outputs. Modeling was performed in the frequency domain with subsequent transformation into the time domain. Comparison of measured and computed transient self responses showed that good fit requires taking into account (1) interaction of each line with its own image current, (2) mutual inductance of the two lines, and (3) skin effect in the wire. As a result of mutual inductance, the parameters of the lines and, hence, of the whole loop depend on local conductivity, which, at least in principle, may allow one to infer the resistivity of shallow subsurface from current turn-off responses. A real ungrounded horizontal loops lacks symmetry at early times and its magnetic field differs from that predicted by the conventional methods of induction soundings.

An algorithm for estimating the parameters and correcting the geometric distortions for the unknown focal length is obtained. A relationship between the directional field and the values of geometric distortion parameters is found. The relationship makes it possible to transform straight scratch images into horizontal lines. Results of experimental investigation are presented. They prove the possibility of using the directional field for solving the problem of correcting the geometric distortions of images obtained in track or ballistic investigations.

Measuring crystal diameters during Czochralski growth is investigated. An image of the crystallization meniscus zone is analyzed. Informative parameters are determined for finding crystal diameters. An algorithm for calculating the diameter of meniscus applied for crystal growth control is described. Results on operation of a sensor using the algorithm during real crystal growth are presented.

Applying the ant colony algorithm for solving the problem of parametric fuzzy model identification is presented. Transition from continuous optimization to discrete one via constructing a complete oriented decision-search graph is determined. A gradient algorithm is considered as the second optimization step. Experiments for analyzing the performance of the algorithms for optimization and fuzzy system are described.

The algorithm for reconstructing a 2D input signal (the image measured) by a finite realization of a 2D signal at the digital optical recording system output with the use of the fast Fourier transform is analyzed. The image reconstruction error is estimated.

Reconstructing the phase distribution of scalar speckle fields arising under light-induced scattering in a photorefractive  crystal is considered. A phase distribution reconstruction method based on simultaneous processing of two interferograms obtained for orthogonal planes of converging reference and signal beams is proposed. The method is more advantageous than single-interferogram methods for analyzing interferograms in the frequency domain because it enables to reduce the number of false-detected optical vortices and increase the SNR in phase reconstruction.

A method for physical process approximation using the differential Taylor transformation is substantiated. The power basis is transformed to bases of orthogonal Chebyshev polynomials. It is shown that the convergence of series is substantially increased by transition to expansion in Chebyshev polynomials of first kind and shifted Chebyshev polynomials. An algorithm for calculating differential spectrum discretes is formulated. It is observed that in the Chebyshev bases, the value of spectrum discretes decreases constantly as their number grows. In this case, it is possible to stop computing the discretes as they achieve the required small value, but this cannot be done in the power basis. Numerical examples illustrate the advantage of the proposed approach.

The average and maximum number of positive overshoots of the multiparticle Doppler signal envelope for the given threshold and also the average durations of positive and negative overshoots as a function of threshold are found. It is shown that the average duration of the positive envelope overshoots is inversely proportional and the average duration of the negative overshoots is proportional to the relative threshold. A tradeoff threshold value that ensures the required measurement accuracy for an admissible level of signal information loss is found.

The paper presents Petrushevskaya

The paper is concerned with a topical direction in studying A.P. Platonov

The article considers the functioning of folklore citations, allusions, reminiscences in the stylistic system of

This paper investigates the problems of functional-artistic significance of mythologemes in the narrative

The paper attempts to apply the methods originally employed in psychology, philisophy, and cultural studies to studying epos. The value system reconstructed on the basis of the analysis of the Siberian peoples epos is described. Having compared the specimens of epos of various peoples (Altaic, Buryat, Khakas, Shor, Yakut ) the author concludes that the loci communes

The paper analyzes the language peculiarities of the Khakas heroic epos which form the basic stock of artistic-poetic tradition. It is shown that the vocabulary of the Khakas heroic legends contains archaic words reflecting certain epochs, loan words resulting from language contacts and, of course, spoken language words for the epic legends are a genuine genre of oral folklore poetics. As a whole, all these language means form a folklore language.

Based on the field investigations and the materials published, the modernization of the shaman initiation rite and the shaman rite accessories by means of

The paper is devoted to the description of a music component of the shaman rite practice. The author deals with the rite plot structure, the particular features of mu

The paper investigates the role of the verbal com

The accumulating abilities of various natural indicators of mercury pollution present in marsh and urban ecosystems are compared. The experimental data on mercury content in the atmospheric air, urban soil, peat, lichens, mosses, mushrooms and berries are reported.

The forms of zinc compounds under the polyelement and zinc kinds of pollution of light- and dark-chestnut soil are studied. It is established that the initial relations between the element forms changes under any kind of pollution. Zinc accumulation in the most mobile forms with an increase in soil pollution was detected for both kinds of pollution. In the case of the polyelement soil pollution, the mobility of the element is much higher than that in the case of the monoelement pollution. Different capacities of the soil kinds under investigation to zinc fixation were determined. It was revealed that the basic mechanism of zinc fixation in polluted soil is ion exchange absorption.

The results of reconnaissance estimation of the occurrence and scattering of uranium over different environmental components (bedrock, soil, bottom sediments, surface water) of Pribaikalia are reported.  Wide occurrence and high variability of the content of this element in the environment of this region are demonstrated; in some anomalous regions the uranium content many times exceeds the regional background level. A dual genesis of anomalous fields was established; it is natural and industry-related. The re-distribution of uranium between different components of the environment of Pribaikalia is essential.

The ground polluted with oil products was analyzed at a depth of 0,5-7,8 m (loamy soil), 11,5-13,0 m (gravelite), 13,0-15,0 m (siltstone). It was shown that the distribution of oil products and microorganisms in the ground over the profile depends on the hydrogeological properties of the rock (porosity, filtration coefficient). The number of aerobic heterotrophic microorganisms varied from 10-10 ufc/g, the fraction of hydrocarbon-oxidizing ones increased with depth from 30 to 85 %. The number of anaerobic microorganisms was comparable with the number of aerobic ones. The number of psychrotrophs and psychrophiles increases with depth; in the lower horizon these organisms prevail over the number of mesophiles.

Specific features of microbial colonies in frozen mountainous taiga industry-affected landscapes in the Elkon uranium ore region at the territory of Southern Yakutia are revealed: the high number of ecological trophic groups of microorganisms (2,0  10 - 7,6  10 c/g), comparable with the density of microbes in meadow steppe soil of Central Yakutia, and a special character of their distribution over the soil profile depending on the uranium content of the soil. In the soil of uranium-polluted pit, an increase in the number of individuals in al the investigated groups of microorganisms with a decrease in uranium content to 161 mg/kg. In other samples of this pit, disappearance or a decrease in the number of microorganisms by 1-2 orders of magnitude with an increase in uranium content of soil is observed. Unlike for the polluted pit, the number of microorganisms in the soil of native landscape remains high over the entire soil profile. Estimated correlation of the number of individuals of the basic ecological trophic groups of microorganisms with such factors as uranium content, temperature and humidity of soil showed that the connection with the concentration of this radionuclide was strongly negative in the radiation-polluted alluvial soil ( = -0,6), while a strict dependence between the number of microorganisms and soil temperature was revealed for the non-polluted soil ( =

The structure and function

For roove beetles in the Shelekhovo district of the Irkutsk Region as an example, the effect of industrial pollution on the forest communities is demonstrated. The taxonomic composition, relic categories, life forms, ecological and size groups, biotope membership are revealed, the degree of generality of roove beetle complexes at the investigated grounds are analyzed. It is stated that the number of ubiquists and saprophages decreases with an increase in the distance from the source of pollution; the index of species sensitivity to the anthropogenic stress is close to the critical one at the ground laid in Shelekhovo.

The element composition of seven species of pileate fungi from the Ust-Koksa region of Mountainous Altay was investigated by means of X-ray fluorescence analysis involving the synchrotron radiation (SRXRF method) for the purpose of revealing the species concentrating heavy metals and evaluating the ecological status of the territory.

The ecological features of some faunistic groups of hydrobionts of the Baikal and Siberian faun

Peculiarities of the post-fire development of larch () phytocenosis in the north of Central Siberia in Evenkia are considered. Morphological parameters of trees, the structure, growth and biological productivity of the larch tree stand, shrub layer, ground floor vegetation, and the accumulation of dead organic mass are analyzed and discussed.

The data on the recovery of soil as the component of the ecosystem on the experimental grounds differing from each other in the methods of recovery works are presented. It is shown that a substantial intensification of soil recovery occurs when a set of methods aimed at the recovery of the biological circulation of the plant material is used, n

The data on the qualitative and quantitative composition of zooperiphyton from the Ob river in its mid- and downstream are reported, revealing the basic factors affecting its growth. Over the major part of the river length, the zooperiphyton constitutes a continuum which is disturbed at the regions subject to pollution. It is found that the communities with the domin

It is shown by means of gas chromatography - mass spectrometry and IR spectrometry that the formation of the composition of organic impurities in the water system of the Tom river basin occurs under the influence of natural and anthropogenic factors. The precedence of the latter is evidenced by the prevalence of the organic impurities originating from oil in the river region under investigation (paraffins, isoparaffins, naphthenes, aromatic hydrocarbons); other pollutants of anthropogenic origin are also present (phthalates, carboxylic acids and their esters, phosphates). The qualitative and quantitative composition of organic pollutants disposed into the river from each industrial zone is investigated.

The features of the phytocenotic organization of algae groupings of dumps in the Kuznetsk Basin are considered. Algae groupings differing in composition of dominant species and biological spectra were revealed. In addition, some features of the vertical distribution of algae species were detected.

The problems concerning mutual relations of the sea colonial birds and plants on the northern coast of the Okhotsk sea are considered. The birds form huge flocks on small islands thus transforming the island landscape and forming specific vegetation in nesting sites. Depending on the intensity of ornithogenic load, different relations between the productivity of plant communities and their species richness are observed. As a rule, flora depletion occurs. Specific ecobiomorphs are formed for the plants which are prosperous at rookeries as a response to the intensive action of birds. On the islands of the northern part of the Okhotsk sea, hummocky gramineous plants represented by pine purple grass existing on the majority of nesting colonies are of the highest significance.

On the basis of an