Home – Home – Jornals – Russian Geology and Geophysics 2011 number 4

The magmatic characteristics of the Levant were investigated by combining recompiled regional scale magnetic maps, revised petrophysical and gravity databases, and previous interpretations. In the study area, the inclination of the Earth's magnetic field vector is low and the total magnetic intensity map is, therefore, difficult to interpret for location and strike of magnetic bodies. Hence, a pole-reduced magnetic map was compiled. The integrated interpretation of magnetic and local gravity anomalies allowed for the estimation of depth and size of magmatic bodies and, in some cases, permitted identification of their composition. Reliability and accuracy of the results were approximated by forward modeling and by comparison with seismic reflection and drillhole data.
The study area was divided into five regions of consistent regional-scale magnetic patterns with more or less distinct boundaries. This was based not only on recognition of formal magnetic patterns but also on correlation with known (or expected) geology. The strong coincident magnetic and positive gravity anomalies probably correspond to ophiolite massifs in the northern part of the study area and basic magmatic intrusions in the southern part. Strong magnetic anomalies, which are not associated with positive gravity anomalies, most likely correspond to Mesozoic and Cenozoic volcanics located mainly in the central part of the region. The absence of magnetic anomalies in some areas suggests the lack of basic magmatic bodies (volcanic or plutonic) but provides no information on the presence of acid magmatics (granite, etc.).

We have modeled central-loop and coincident-loop transient responses of a magnetically viscous layer sandwiched between two nonmagnetic ones. The coincident-loop transients show exponential voltage decrease (at a fixed delay time), at any thickness h ₂ of the magnetic layer, with an increasing depth to the latter ( h ₁) or the loop height if the layer is exposed on the ground surface. The patterns of central-loop transients are different from those of the coincident-loop ones and from one another for thin and thick magnetic layers. Namely, the voltage first rises to its maximum and then falls as the depth to the magnetic layer ( h ₁) increases, if it is thin: The thinner the layer, the more prominent the peak. If the layer is thick, the voltage decreases monotonically with its depth (or with loop height above the ground). Voltage grows, first rapidly and then progressively more slowly, at ever greater thicknesses of the magnetic layer in both loop configurations. At large h ₂, the effect from the magnetic layer becomes similar to that from a magnetically viscous half-space. These features of the transient responses have to be taken into account in planning and conducting TEM surveys, as well as in a geological interpretation of the TEM data affected by natural and/or man-caused magnetically viscous ground. In the general case, the turn-off of the transmitter current induces eddy current in the ground beneath the loop, which decays at a rate proportional to the ground resistivity. The eddy current decay and magnetic relaxation processes being independent at conductivities (resistivities) common to the real subsurface, the effect of the former can be allowed for using the superposition principle. This principle implies that the total response of a magnetically viscous conductor is a sum of the magnetic relaxation and eddy current components.

The large earthquake that shook the southern part of Lake Baikal on August 27, 2008 has received much scientific and public interest. The occurrence of the event in the high-seismicity Baikal rift was not surprising, but its origin time was, as usual, unexpected. We discuss the geological conditions of the earthquake, its macroseismic effects, and some data interpreted as its precursors. A special focus is made on preseismic changes in dissolved helium in Lake Baikal. Studying helium patterns in a deep freshwater lake in an active seismic area is a pioneering experience that appears to have no match in the world earthquake prediction practice.

We consider the geologic occurrence and PT -conditions of the generation and crystallization of siliceous melts that formed volcanic structures within the Altai collisional system of Hercynides. The data on the geologic occurrence, internal structure, and petrogeochemical age of rocks are presented, as well as results of the thermobarogeochemical studies of inclusions in minerals. The performed investigations showed the presence of siliceous dacitic melts in the studied volcanic structures. These melts were generated in the lower crust (~10 kbar, 1000-1200 ?C) as a result of the partial melting of crustal substrates under the influence of high-temperature mantle melts.

The paper presents new data on geochemistry (major and trace elements, isotopes) and petrology (composition of phenocrysts and mineral thermometry) of basalts from the Early Cambrian Katun' accretionary complex of the Kuznetsk-Altai island arc (Gorny Altai). We also discuss the geodynamic settings of the formation of basalts based on petrological, geochemical, and isotope data taking into account their relationships with associated sedimentary rocks of oceanic origin and with terrigenous sedimentary rocks of the accretionary complex. The Late Neoproterozoic basalts associated with siliceous sediments are characterized by medium TiO₂ and Zr/Nb, flat REE patterns and Nb/La_PM < 1 (MORB). The oceanic floor basalts are represented by high- and low-magnesium varieties. The Early Cambrian basalts (Manzherok Formation) formed in an oceanic island setting (OIB). They occur in sections consisting of paleo-oceanic island basalts alternating with siliceous-terrigenous-carbonate sediments of slope facies. The Manzherok basalts are characterized by high crystallization temperatures (1175? C) and are enriched in incompatible elements (LREE, Ti, Nb), whose variations suggest a mantle plume source and variable degrees of partial melting in the spinel and garnet stability fields. The low- to high-Mg Middle Cambrian basalts of the Ust'-Sema Formation occur as subparallel dikes and lava flows, which cut and overlap the accretionary complex. The basalts are characterized by low TiO₂, Nb, LREE, high Zr/Nb and, compared to the OIB, lower temperatures of crystallization, 1047? C and 1138? C for the low- and high-Mg varieties, respectively. Geochemically, the low-Mg basalts of the Ust'-Sema Formation are close to MORB, and the high-Mg basalts, to island-arc tholeiites. Such a combination of geochemical and geological data suggest that the low-Mg basalts of the Ust'-Sema Formation formed during ridge subduction, and the high-Mg basalts formed in a suprasubduction setting, at the crust-mantle boundary.

Gold and silver sulfides were synthesized from melts Ag_{2- x} AuxS ( x = 0.1, 0.4, 0.8, 1.6) in the system Au-Ag-S with Au/Ag = 0.1-7.4. Optical microscopy, X-raying, electron probe microanalysis, and scanning electron microscopy were used to identify and analyze the solid products. It has been established that aсanthite, solid solutions Ag_{2- x} Au _x S ( x < 0.5), and electrum are produced in the Ag-rich binary system Ag₂S-Au₂S. Petrovskaite, high-fineness gold, and sulfur are produced in the systems with low Ag contents ( x > 1). The systems with an intermediate composition produce petrovskaite, uytenbogaardtite, and solid solutions Ag_{2- x} Au _x S (0.5 < x < 1). The results of experimental studies together with data on the compositions of natural gold and silver sulfides suggest that the wide variations in Au and Ag contents in uytenbogaardtite and petrovskaite from different deposits are, most likely, due to the inhomogeneous structure of mineral grains and the presence of solid solutions Ag_{2- x} Au _x S. It is assumed that gold and silver sulfides crystallizing from Au-Ag-containing sulfide melts might be of magmatic genesis. Poorly extractable gold in sulfide ores might be present as microinclusions of Au-Ag sulfides.

Experimental results concerning the radon exhalation rate from samples of building materials which were collected from the districts of Muzaffarabad and Neelum Valley, Azad Kashmir, Pakistan are presented. The study aims at assessing the contribution of building materials toward the total indoor radon exposure to the inhabitants of the studied area. In this context, samples of building materials, namely, soil, sand, gravel aggregates, and bricks, were collected from different parts of the districts of Muzaffarabad and Neelum Valley. After processing, the samples were placed in plastic containers, and box type radon detectors were installed in it at heights of 25 cm above the surface of the samples. The containers were then hermetically sealed. After 80 days of exposure to radon, CR-39 detectors were etched in 25% NaOH at 80? C for 16 h and counted under an optical microscope. The measured track densities were related to radon concentrations. Radon exhalation rate from soil, gravel aggregates, sands, and bricks varied from 171 ± 11 to 344 ± 11, 168 ± 17 to 322 ± 11, 366 ± 8 to 649 ± 8 and 184 ± 14 to 231 ± 14 mBq/(m²·r), respectively. Present data have been compared with the published data for other parts of the world.

Pollen and AMS¹⁴C analyses of bottom sediments from the upper nine meters of the Lake Kotokel' section were carried out. The regional climate and landscape dynamics during the Late Glacial and Holocene have been reconstructed with an average time resolution of ~120 years. It is shown that the climatic conditions in the Kotokel' basin during Termination I (~15.5-11.0 ka) were characterized by short drastic changes resulting in reorganization of landscapes and vegetation. Five short (400-1200 years) intervals have been recognized: 15.5-14.7, 14.7-14.3, 14.3-13.2, 13.2-12.5, and 12.5-11.7 ka. In the early Holocene (~11 ka), the climate became less continental and stayed such till ~7 ka. Later on, it again became more continental, which led to a significant decrease in average annual precipitation and winter temperatures and an increase in average summer temperatures.
The pollen record from Lake Kotokel' agrees with the general climatic trend for the Northern Hemisphere. The amplitude of vegetation and climate variations during the Late Glacial is best expressed as compared with the previous regional pollen records. This is probably because the ecosystem of the small lake localized deep inside the continent, at the boundary of two large ecotones (forest and steppe), is highly sensitive to moisture deficit.
The new dated detailed pollen record from the Kotokel' bottom sediments might be regarded as a key for the reconstruction of variations in regional vegetation and climatic dynamics for the last 15-15.5 kyr. The results obtained refined the character of changes in regional vegetation, and the reliable age model permitted intra- and interregional correlations of environmental changes.

One analytical relation needed for calculating the probability of errorless readout of random discrete images by integrators with two threshold levels is proved. A specific feature of this study is the fact that the relation proved in this paper has been first obtained through analytical calculations on a computer.

Operation principles of locally spatial filtration algorithms and wavelet filtration algorithms are described. Numerous computational experiments are performed with filtration of two different images distorted by noise with different statistical natures (white, color, and pulsed). Based on the analysis of the results obtained, recommendations on using the image filtration algorithms considered are given.

A new algorithm for detecting abandoned objects is proposed. The algorithm is based on analyzing the space and time characteristics of the overall background, background consisting of stationary objects, and current image of the video sequence. The algorithm can operate under conditions of short-time overlapping of the abandoned object, has a moderate computational complexity, and is designed for application in video surveillance systems

A method of digital filtration of experimental data sequences with the use of approximation spline functions is proposed. A problem of digital filtration on the basis of such functions is posed, and its general solution is given. An example of constructing approximation spline functions with control at the ends of observation intervals is considered. Results of digital filtration of aerodynamic experimental data with the use of the method developed are described.

Approximation of structure functions (SFs) using orthogonal polynomials in most cases, leads to an incorrect determination of the spectral power density for the obtained orthogonal model. A method for constructing orthogonal models of SFs is proposed based on preliminary shifting of the analyzed SF and using orthogonal functions as the bases. In this method, the expansion coefficients are determined using a numerical-analytical approach, which allows one to determine orthogonal models of SFs with a small approximation error and calculate spectral power density with greater accuracy. The implementation of the algorithms for constructing orthogonal models of SFs in the Laguerre and Legendre bases is considered.

We consider one of the important problems of information theory-the compression of data, in particular images, without loss of quality. An efficient image compression algorithm based on two-step coding. A comparison of experimental results of this algorithm and the JPEG-LS halftone image compression standard confirms the efficiency of the proposed method.

A modified quasioptimal method is proposed to control multielement antenna arrays by optimizing its integral parameters in controlling the complex current amplitudes in some of the array elements. Analytical estimates showing a significant reduction in computational effort were supported by calculations

A regularization method for estimating the directions to sources of coherent radio signals was developed which takes into account the vector nature of the electromagnetic field of incident waves and complex radiation patterns of antenna elements and does not depend on the incident wave polarization.

Implementation of a coupled finite element method of modeling of diffraction of electromagnetic waves on periodic inhomogeneities on substrates and in free space is discussed. The region including a periodic distribution of permittivity and permeability is covered with a finite element mesh. The variational equation incorporating field values in mesh nodes is minimized in accordance with the finite element method. The Rayleigh expansion is applied to field values in homogeneous half-space domains below and above the calculation domain including the inhomogeneity. Numerical experiments are performed to analyze the solution convergence dependence on the element size.

A noiseless algorithm for analyzing phase-shifting interferograms is proposed

A stereoscopic visual space constructed on the basis of a three-dimensional Trehub's retinoid is considered. For the eye model used, this space is demonstrated to correspond to the Renaissance perspective observed by a cyclopean eye, with the sight range being proportional to the linear parallax of points. Advantages and drawbacks of proposed models of visual perception are analyzed

A gas-droplet flow generated by a pneumatic injector with internal mixing is studied by optical methods. The fractional composition and the spatial distribution of liquid droplets for different fractions are measured, as well as the mean velocity field.

A laboratory system for recording and analyzing acoustic emission was designed and experimentally investigated (tested). A block diagram and the operation algorithm of the system are presented. The relationship between the results of low-frequency, high-frequency, and statistical processing of recorded data and the physical features of input signals is shown using as an example simulated acoustic signals in the various units of the designed system. The system was tested on real test objects in the case of three-point bending of nitrided steel specimens with various thicknesses of the hardened surface layer. It is shown that crack formation leads to emission of signals with an amplitudes of up to 4 V, whereas during deformation in the absence of pronounced cracking, the amplitude of the amplified signal does not exceed 0.5 V.

The author analyzes the level of  military art development among the Russian soldiers and  Siberian Tatars as well as the role of military factor in defending the southern boundaries of Western Siberia from Turkic and Mongolian nomads in the end of the XVI - first third of the XVII centuries when there was a real possibility of the Siberian Khanate's restoration.

The article deals with the management of the West Siberian yams during the Late Middle Ages. The author determines the order of appointment to management positions of the yam prikazchiks; reveals the scope of their authority; the level of their independence; forms of material support. The conclusion is drawn that these functionaries played an important role in organizing the transport routes in Siberia.

The article deals with analysis of the reasons underlying the crisis in the Nerchinsk Mining District which led to liquidation of the silver-refining industry in Eastern Siberia. Based on the archival materials the author proves that the pre-Cabinet era paved way for the future crisis of the Nerchinsk plants.

The paper studies the process of cattle-breeding development in the Kudinsk district in the XIX century. The author considers the Buryats' cattle numbers, the structure of their herds, the correlation between different types of agricultural lands and buildings in the Kudinsk district in the XIX century. He also determines factors that influenced the Buryats' cattle-breeding development, including the natural environment, state policy, technological innovations.

This article considers the authorized and real staff size of the Yeniseisk provincial administration in 1822-1917. Based on the previously unknown documents and archival materials the author considers peculiarities of the Yeniseisk government administration, the actual and relative number of officials holding the higher ranks of field and non-commissioned officers. The author also describes trends of the Yeniseisk administration development and shows how its size changed over time.

This paper attempts at analyzing the array of special architectural documentation, catalogues of museum collections and unpublished archival data in order to create a well-built model which will help emphasize typical features of the Christian churches architecture in one of the Western heterodox confessions of Siberian Region of the Russian Empire. The author finds out to what extent the church architectural canon depended on the directives from the state authorities and local administrations.

The paper deals with some aspects of resettlement policy in Siberia in the end of the XIX - the beginning of the XX centuries. The author considers main undertakings and contradictions that existed in the resettlement policy. The article is written on the wide range of archival materials for the first time introduced for scientific use.

The article deals with newspapers published in the end of May - the middle of November 1918 in Siberia under the rule of the anti-Bolshevik government. The author studies the circumstances under which the newspapers were published, shows changes in quantity and contents of the local press. It is stated that liquidation of the Soviet power in Siberia led to reestablishment of the freedom of speech and radical changes in the sphere of periodical press. Newspapers as a social institute preserved their independence from the authorities despite the escalation of Civil War and evolution of the political regime of democratic counter-revolution towards authoritarianism.

The article analyzes the 1920s discussions in the Yakut ASSR between the Sakha Omuk' (the Sakha People) cultural-educational society members and the Party-Soviet organs in which they put forward the questions of interrelations between the power and intelligentsia; activities of national associations in the period of NEP, et al.

The article written on the paperwork and documents of the Communist party bodies analyzes activities of the twenty-five-thousanders - the workers, who were sent to the Siberian region from industrial centers for conducting the forced collectivization. The author reveals positive and negative factors that affected these workers' adaptation to the new social functions and comes to conclusion that about one fourth of all mobilized workers could not manage their task.

The article deals with legal collisions driven by the notorious law of spikelets passed in 1932. The author shows the scale of repressions connected with execution of this law in Western Siberia; explains reasons of its gradual exclusion from legal practice.

The paper is devoted to the deportation of Armenian population from the southern regions of the Soviet Union to the Altai territory in 1949. For the first time in historiography the author clarifies the numbers of this particular category of forced migrants, as well as the structure of their settlement and local authorities' activities providing adaptation and distribution of the migrants within the region. The paper is written on the basis of new data from the declassified documents kept in the State Archives of the Altai Region.

The article considers activities of the governmental bodies and geological survey organizations searching and developing the Far Eastern ore deposits of uranium, thorium etc., needed for production of the nuclear and thermonuclear weapons. The author reveals the level of financial and logistical support of the geological exploration, mining and smelting enterprises and shows the results of their activities.

The paper deals with some of the social characteristics of the technocratic elite of the Angara-Yenisey region in the 1960-80s. The author identifies trends of the technocratic elite's socio-demographic development in the second half of the twentieth century and explains the reasons of this process.

The article's purpose is to examine the prospects of demographic development in rural areas near small towns in the context of Russia's urbanization. The urgency of the problem is determined both by the consequences of the rural area's active depopulation in the second half of the XX century and by the necessity to clarify the role of small towns in the urbanization process. The author considers main types of the Russian small towns and analyzes the specific features of their formation and functioning. He also defines different types of demographic modernization of rural areas adjacent to small towns. The author concludes that the most natural model of demographic modernization of rural area is offered by small satellite towns located near metropolitan agglomerations.

The present article deals with a fundamental work of A.I. Levshin «Description of Kirghiz-Cossack or Kirghiz-Kaisatsk hordes and steppes», published in 1832. The work is often cited by the researchers so it proves the book's relevance and importance for studying history and culture of Kazakhstan. Its author presents different archival materials, the results of his field surveys, gives a detailed geographical description of Kazakhstan. For the first time in historiography he referred to the issues of the Kazakhs ethnogeny, their material and spiritual culture. Levshin's book has been an important source of data on politics, economy, culture and family life of the Kazakhs.

The aim of publication is to study the history of ornamented items production in the 1920s-1930s at the Zlatoust factory. Problems of industrial culture are analyzed on the basis of the interdisciplinary approach which allows studying the history of Zlatoust artistic metal production - a special sphere of the Urals metallurgical production, an original phenomenon, which appeared as an alloy of science, production process, craft and art. Being the artifact of industrial heritage it also belongs to the field of art. The research is based on facts and events supported with documentary witnesses and archival sources, which were published for the first time.

The article is devoted to one of the groups of special deportees which appeared in the Stalinist state and consisted of the frontiersmen of Belorussia and Ukraine. These groups were deported to the Far East in transit through Siberia. The author shows distinction between these deportees and the majority of exiled kulaks; reveals the specific character of interregional relationships between different OGPU bodies being in charge of resettlement. The author investigated the reasons of temporary separate resettlement of family heads (in Yakutia) and other family members (in DVK), describes a painful process of their reunification, their living conditions in special settlements and their labor in the areas of gold mines.

For the first time in historiography the author analyzed how the museums of the SB RAS and their activities were represented in a specialized periodical Almanac «Museums of the Russian Academy of Sciences. She highlighted several groups of articles based on their contents - museographical, analytical, topical and doctrinal articles. It was established that active publication of materials contributed to determining the role and significance of Siberian museums in the system of science museums, reflecting their role in the process of formation of scientific collections and translation of scientific knowledge about the Siberian region. It also provided realization of their adaptive capacity and integration into the Russian museum community.