Home – Home – Jornals – Avtometriya 2008 number 3

New data on geochemistry of incompatible trace elements (Nb, Zr, Hf, Ti, Y, REE) in garnets (Ga) and clinopyroxenes (Cpx) from deformed high-temperature garnet lherzolites, harzburgites, and garnet megacrysts from the Udachnaya pipe are presented. According to textures and petrographic composition, the deformed Ga-bearing peridotites are subdivided into coarse- and fine-porphyroclastic. Rocks of the first type (Ga-lherzolites) are enriched in Ga and Cpx (up to 30% each); among them, there are xenoliths with deformed Ga, Cpx, and Ol megacrysts. Deformed fine-porphyroclastic peridotites (Ga-lherzolites and Ga-harzburgites) are depleted in Ga (≤10%) and Cpx (≤3-5%). Four Ga megacrysts are typical of a Cr-poor association (0.33-1.63% Cr₂O₃; 0.56-1.05% TiO₂; Mg# = 0.67-0.86). Garnets from deformed high-temperature coarse-porphyroclastic Ga-lherzolites are similar in geochemistry to Ga megacrysts: Their chondrite-normalized REE curves rise smoothly from La to Yb, and their spidergrams show peaks of Nb, Zr + Hf, and Ti. The narrow marginal zones of Ga grains from Ga-lherzolites are enriched in LREE. The peaks of HFSE in the Ga curves are smoothed out. The element patterns of garnet from fine-porphyroclastic Ga-lherzolites and Ga-harzburgites show a sinusoidal distribution of REE and Zr + Hf and Ti minima on the spidergrams. The element patterns of Cpx from both types of rocks are nearly the same: The curves are convex in the field of LREE, drastically drop from Nd to Yb, and have minima of Nb, Zr + Hf, and Ti. The curves of melts (L) equilibrated with Ga (calculated from partition coefficients) show a drastic enrichment in LREE and peaks of Nb, Zr + Hf, and Ti for garnet from deformed coarse-porphyroclastic lherzolites and megacrysts. The L curves of fine-porphyroclastic lherzolites and harzburgites have distinct minima of Zr + Hf and more sharply slope from Nd to Yb. The L curves of Cpx have minima of Nb, Zr + Hf, and Ti and lie near the field of basaltoid kimberlites from the Udachnaya pipe. All these data are consistent with the model of percolative fractional crystallization. The matter of mantle plume arrived from the mantle transition zone might have been the source of asthenospheric liquids inducing specific magmatic metasomatism at the continental lithosphere-asthenosphere boundary. The source material was enriched in majorite and silicate-perovskite or in ancient oceanic crustal matter.

More than 1000 pyropes from the Muza (J₃) and Ivushka (D-C) (northeastern Siberian Platform, and Khorkich (Mz) (southwestern part of the platform) kimberlite pipes, alluvial deposits of the Muna-Markha area, and granular peridotites of the Udachnaya pipe have been analyzed for major and some minor elements. As a result, a group of pyropes was distinguished whose composition is not typical of the lherzolite paragenesis (LAC pyropes). They are predominant in the Muza pipe and are widespread over the world. This group is described as a separate paragenetic type. In all known cases, LAC pyropes belong to granular clinopyroxene-bearing harzburgites, and in situ conditions for this suite are typically below 50 kbar and 1000

Isotope dating of ultrapotassic magmatism in the central Chukchi region was carried out. Based on the Rb-Sr isochron age of monzonites from the Linkor stock (107 ± 2.2. Ma) and using earlier obtained geochronological isotope data, we have estimated the time of one of the stages of ultrapotassic magmatism, 107-113 Ma. Igneous rocks of this age occur throughout the central Chikchi region, which suggests their genetic relationship with some great geodynamic event there, likely, the accretion of the Mainit island arc to the Chukchi microcontinent.
The results obtained permit the reconstruction of the geologic history of the region and can be used to construct more detailed geodynamic models.

The lava sequence of the Alag-Zaar-Gol River catchment (southern Hövsgöl area, northern Mongolia) is an accretionary prism composed of metamorphosed basalt and, less often, andesite alternating with siliceous tuff. The protolith of metabasalts may have formed in island-arc or ocean-island environments, and andesites were, possibly, derived from ocean-island varieties. Volcanics of different types are found coexisting within the same thrust sheets, which may be due to thrusting in the course of postmagmatic tectonic events.

Late Neoproterozoic (Late Vendian) basalts of the Paleo-Asian Ocean are found as fragments incorporated in the Kurai accretionary zone, Gorny Altai, Russia. Detailed study of their geochemistry and relationships with associated sedimentary rocks allowed us to recognize three types of basalts: (1) lavas depleted in REE, Nb and Ti, compositionally similar to N-MORB and associated with thin-bedded oceanic siliceous sediments; (2) basalts of transitional compositions, and (3) basalts enriched in the above elements; basalts of types 2 and 3 are similar to Pacific intraplate basalts and are associated with carbonate

Organic matter of the Upper Jurassic-Lower Cretaceous highly carbonaceous black-shale Bazhenov Formation in the central part of the West Siberian sea basin is composed of predominantly sapropelic planktonogenic material, which was earlier assumed to have derived from siliceous-skeletal microorganisms (first of all, radiolarians) and nonskeletal ones (bacteria and algae). Comparative analysis for organic carbon in the formation rocks and in radiolarites and radiolarian oozes from some other areas showed that the siliceous-skeletal organisms make up <1% of the organic matter of the Bazhenov Formation. This is confirmed by correlation analysis of two main types of Bazhenov rocks - siliceous-argillaceous (bazhenovites) and argillaceous (mudstones), - which showed the absence of correlation between the contents of organic carbon and quartz (which is mainly authigenic) for both rocks.

We study crustal deformation in the northern Tien Shan as recorded in strain rates derived from earthquake and GPS data. Geodetic strain rates indicate general shortening along the N-S component and agree with Quaternary fault slip rates and with the strain field obtained from earthquake mechanisms, all being signature of overall north-south contraction in the region.
The GPS strain field changes quickly in time, especially in the W-E direction, and is produced by a joint effect of elastic, plastic, and quasi-plastic deformation. The seismological strain field reflects the effect of external tectonic forces applied to seismogenic crust and the stress change due to crustal heterogeneity and geometry of the study area. Seismological and GPS strain rates carry information of different kinds. The former reflect formation of local structures mainly in the brittle crust, such as a local pull-apart in the center of the Lake Issyk Kul area, whereas the latter provide clues to mechanisms that drive the geological evolution of the mountain terrain as a whole. The current evolution may involve the effect of density instability at the lithosphere-asthenosphere boundary.

The Earth's surface topography disturbs the thermal field making measured superficial thermal gradients (heat flow) higher or lower than the deep value. Topographic disturbance can be removed from data by applying the respective correction. We estimated the effect of the rugged bottom of Lake Baikal on thermal gradients from the vicinity of boreholes BDP-93 and BDP-96 drilled in the lake sediments and deep borehole L-2 on the western shore of the South Baikal basin near Listvyanka Village. The corrections were computed using a Monte-Carlo simulation algorithm specially designed to quantify the effect of surface topography on the thermal field. The performance of the algorithm was checked by a test example. The corrections turned out to be vanishing in the area of underwater drilling but significant at L-2 where the thermal gradient in the upper 1 km of rocks was about 20% underestimated. The corrected heat flow in L-2 data increased from 50 to 60 mW/m² and approached the values measured in the central South Baikal basin.

The Oneka intrusive complex, recognized on prospecting for hydrocarbons in the western Siberian Platform, in the northern half of the Bakhta megablock (Tunguska syneclise), holds a special position among the known and new large-scale manifestations of intrusive trap magmatism. During the process, original data on the distribution of traps in the 4.2 km thick platform cover were obtained. Diverse in morphology and size, the intrusions are of the same genesis, composition, and character of intrachamber differentiation and form a

Experiment with poikilitic garnet at 3 GPa and 800

We present results of computations on the interaction of solid-phase electrum-argentite-pyrite (weight ratios 2·10^-5 / 2 · 10^-3 /1 and 2·10^-5 / 4·10^-2 / 1>) association with Cl-containing aqueous moderately acid solutions (0.5m NaCl, pH = 3.08) at 300

We suggest a model of the continental collisional framework of the southern Great Altai (Central Asia) produced by the convergence of the Tuva-Mongolia and Jonggaria terranes (microplates) during the latest Permian-Mesozoic and Cenozoic tectonic activity. The collisional structures in the region classified on the basis of their geometry and deformation style, dynamic metamorphism, and compositions of tectonites are of three main types: (i) mosaic terranes made up of large weakly deformed Paleozoic blocks separated by younger shear zones, (ii) collisional deformation systems involving post-Paleozoic structures, parallel faults oriented along collisional deformation systems, and relict lenses of Paleozoic orogenic complexes, and (iii) isolated zones of dynamic metamorphism composed mostly of collisional tectonites.

Study of morphostructures and Cenozoic deposits is important for reconstructing the history of the recent evolution of East Sayan and search for buried gold placers. Regional positive morphostructures of mountains with well-pronounced relief stages have been recognized in the Altai-Sayan area. The upper stage is referred to the Cretaceous-Paleogene; the middle one, to the Miocene-Pliocene; and the lower stage is dated at the Late Pliocene-Early Pleistocene. Negative morphostructures are recognized as a chain of intramontane basins and graben-like valleys of the Transbaikalian type. Troughs in the section bottom are filled with Cretaceous-Paleogene clayey crusts of weathering overlain by Neogene-Pleistocene deposits of complex composition. We studied the sections of Cenozoic deposits in the valleys of the Shinda and Verkhnyaya Chinzheba Rivers and made their palynological description.

High-density array MT soundings of the crust in the seismically active northern Tien Shan were performed using Phoenix MTU-5 stations in the Bishkek Geodynamic Polygon, at the junction of the Chu basin and the Kyrgyz Range. The MT transfer functions were determined to an accuracy of 1-2% (amplitude) and about 0.5-0.8 deg (phase) in most of 145 soundings. Preliminary analysis of the collected data aimed at estimating the geoelectrical dimensionality. The Bahr decomposition analysis indicated the presence of local 3D structures in the crust of the area superposed on the regional 2D structure.

The energy balance of a solid subject to fracture has been explored using heat and mass transfer equations with regard to the volumetric and superficial components. In the suggested model, brittle fracture of a cracked solid considered as a heterogeneous two-phase medium is described by an equation analogous to the Griffith's criterion for propagation of a single crack. The derived equation is used, together with estimates of relative change in specific interface area, to study the respective change of free strain energy and pressure in rocks associated with failure.

Obtaining an analytical model of a spatial group point object is considered in terms of quaternion analysis. The point ordering procedure consists in numbering vertices of a convex polyhedron associated with the object. The wire model is a spatial polygonal line passing through all object points without brunching.

A Bayes formulation for the problem of rapid detecting appeared disorders in the probability characteristics of the observed stochastic jump process with values in a sufficiently general phase space is presented. It is supposed that the time of disorder appearance does not depend on the evolution of the observed process and coincides with the moment of one of the process jumps. Recurrent equations for a posteriori disorder probability are obtained. The lower bound for the optimal moment of alarming the happened disorder for minimizing the sum of false alarm probability (without disorder) and the mean time of alarm delay is found.

A uniform approach to constructing intellectual data analysis, or data mining is proposed. The approach is based on using a rival similarity function (FRiS function) representing the way of human estimation of similarity and dissimilarity. A brief description of data mining methods based on this approach is presented. Examples of solving model and real problems by these methods are illustrated.

Sine-cosine transformations on the interval -0.5T ≤ t ≤ 0.5T, which are equivalent to a cosine transformation on the interval 0 ≤ t ≤ 0, are considered. Relationships for the error variance of signal reconstruction are obtained. Depending on the a priori information on the signal, the relationships make it possible to choose for its representation the most suitable orthogonal expansion. A stationary random signal model is used for comparing the expansion with a conventional sine-cosine transformation.

Two methods for increasing the sampling rate in digital oscilloscopes are analyzed. The equivalent-time sampling is carried out via measuring and accumulating a series of oscillograms with a random phase and leads to nonuniform sampling. As a result, for few accumulations, the output noise level increases and the effective number of bits decreases. Interpolation in digital oscilloscopes is performed by sinx/x functions and its errors are determined by the length of the interpolating FIR filter. A table for choosing the filter length, depending on the interpolation coefficient and the normalized band of the reconstruction filter is presented. Obtaining a high interpolation coefficient requires considerable computational power.

The paper analyses the causes and factors of building the economic research institute in Siberia in the 1950th, describes mechanisms for creating the new research center, and formulates the management principles that provided the emergence of a scientific school and long successful work of the institute.

The paper summarizes the theoretic and methodological experience of economic-mathematical modeling and the practice of creating not separate models but a complex of the models of national, sectoral, regional and an enterprise levels. This approach proved to be innovative for the practice of national planning.

The paper reviews the researches made by the Department for Territorial Systems Studies, IEIE SB RAS for nearly 40 years. The author puts emphasis on those which were of actual continuity during all the period of the Department

The paper reviews basic stages in shaping the regional administration school of Siberian researchers who studies issues of regional economic self-sufficiency, regional pre-planning, a programming approach to regional economic policies, complex planning in regions, building regional markets and competitive positions of regions. The author proposes major  ways of how to build a system of regional administration allowing for the present-day conditions when many different regional economic units operate in market and may have economic conflicts, the relationship between governmental and market structures, and a system of forecasting and planning for regional development.

The paper describes the basic theoretical and application-oriented results obtained by scientists of the Novosibirsk school of economic sociology over 1988-2008 and analyzes the logic and peculiarity of the results. The author specifies three periods of the studies concerning the social processes taken place in Russia at that periods and being some answer to the challenges of that time - monitoring of economic reforms, evolution of institutions and the development of new theoretical and methodological frames to analyze Russian society regarded as an integral socio-economic object.

The authors describe the history of the Institute of Economics and Industrial Engineering from the moment of its foundation, and comment the facts and statistics about its 50 years history.

The paper reviews the studies, made for passed years, concerning the multiregional systems applied interregional and intersectoral models; describes basic types of models and characters of their solutions, and discusses how such instruments could be applied to the analysis of the interregional economic interactions, a nuclear and a balance of multiregional systems and identifying effective and non-effective regional coalitions. We also present and analyze the studies concerning the methodology of double-level system modeling

The paper proposes a technique to measure differences in socio-economic indicators for regions. The author applies this technique not only to assessing changes in distance of regional socio-economic indicators but also to describing the nature of shifts and how each indicator defines a relative position of a region. The allowance for measures of inaccuracy of the statistical data used was made.

The major difficulty in modeling federal support is to combine the equalizing fiscal capacities of regions with building conditions and incentives for regional authorities to accumulate their economic (fiscal) potential. The paper analyses one of possible variants of such model where the attempt to harmonize these, generally speaking, contradictory targets was made. To imitate different variants of fiscal capacities in regions which reflect both the production scopes in regions and the horizontal and vertical tax flows, and to find the situations of equilibrium in one or another sense is a key idea of our model concept.

The paper considers a number of provisions of the world and domestic concepts on the regional development which concern the evaluation of Russia regional development or being regarded as basis for a regional policy and proposed officially.

The paper considers how proportions in the large macroregions development have changed in the context of the country

The paper considers a key problem of consumer

The paper analyses the Northern Siberia Trunk-railway Concept developed by the Institute for Regional Policy. It is shown that the Concept does not contain those required provisions which could make the Concept a scientifically valid document going before the implementation of this project and allowing for an uncertainty factor as the project is of a unique scope and complexity. The institutional aspects also require proper elaboration. The technical and economic indicators applied to validate the project proved to be disputable. We suggest that the expected effectiveness of the Project should be compared with other projects concerning the development of the Siberian railway system, and then the priorities of such projects be determined.

The paper analyzes certain aspects of competitiveness between regions on the base of the data obtained by questioning the representatives of authorities and business in Ural region. We focus on the nature and directions of competitive struggle between regions, identifying the indicators of regional competitiveness, the roles which regional administrations play in regional competition and the gist of regional competitive advantages. We also state that the atmosphere of trust should be necessarily built in the society as well as the good relationship between authorities of different levels and business. The important tools to enhance the competitiveness of regions are public-private partnership, clusterization of economies and logical and continuous shaping of regional images and reputations.

The paper describes the character of a hydrocarbonic resource base in Western Siberia and the Republic of Sakha (Yakutia), an economic-geographical location of this area, its economic development, a governmental policy towards it and institutional barriers for developing the oil-and-gas potentials under hazardous climatic conditions of this remote and underpopulated area. The factors why there are many problems in the development of this area are the same that impede the overall development of the oil-and-gas industry in Russia at present.

The paper presents and validates the quantitative estimations and principles of gas supply to new Eastern markets, and describes the problems and threats connected with this. Having analyzed the conditions and perspectives of the natural-gas industry development in Russia, and using analytical data and quantitative information about the systems of gas supply in counties of the Asia-Pacific Region, first of all in the Northeast Asia, we could show the prospects of our cooperation with such countries. In our analysis we used publicly available information of Russian and overseas mass-media including electronic ones, as well as those obtained through our study of the production enterprises and infrastructure in Northeast Asia countries.

To balance the operating rates of an enterprise or corporation is one of the most important factors for building an effective management system. The paper presents one of such methodological approaches. To build such system which include the coordinated management indicators used in different functional subsystems and at different management levels, we propose the use of the optimization models involving innovations to enhance corporate competitive advantages in markets as well as to balance those rates concerning the inside corporate operation.

The paper-presentation analyzes Canadian practices of federal support, the Aboriginal self-development, relations between the federal and Northern governments and mechanisms aimed at better use of natural resources  in the North.

The paper summarizes the output of the Russia-Canada Workshop on "Strategic Planning and Assessment of Regional Programs". The author analyzes the practices of strategic planning in Russia and Canada as well as the possible evolution of strategic planning in Russia in case we would apply the best Canadian practices.