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A brief summary of different viewpoints on the sedimentation model for the Achimov rock unit in West Siberia is presented. The differences in the concepts of the rock unit structure have led to ambiguous approaches to mapping of the boundaries of its area. Our study of the clinoform structural model for Neocomian section yielded geological and geophysical data substantiating the positions of the western and eastern boundaries of the Achimov rock unit.

Granite pegmatites are a unique natural object that makes it possible to study magmatic processes that lead to the formation of ore-generating media and systems. This paper summarizes modern views on phase transformations in aqueous silicate systems at parameters close to those of the transition from magmatic to hydrothermal crystallization. Comparison of phase diagrams and the results of study of pegmatite-forming media permits making conclusions about the crystallization of the water-saturated magmas of miarolitic granite pegmatites. The fluid regime of aqueous granite systems of simple composition, not enriched in fluxing components, is determined mainly by magma degassing or the supply of volatiles with flows of transmagmatic fluids. These processes cause the separation of essentially carbon dioxide or essentially hydrous fluid. During the crystallization of such magmas, crystallization from silicate melt is separated in PT -space and, possibly, in time from the crystallization from aqueous or mixed carbon dioxide-aqueous super- and subcritical solutions. The evolution of chambers of water-saturated granitic and pegmatitic magma enriched in F, B, and alkali metals presupposes the formation of a heterogeneous mineral-forming medium in which crystallization occurs in the magmatic melt at high-temperature stages; as temperature decreases, crystallization can proceed in hydrous fluid, hydrosilicate, and/or hydrosaline simultaneously. Hydrothermal crystallization can also take place in a heterogeneous medium consisting of aqueous solutions of different salinities and vapor or water-carbon dioxide gas mixture. The relationship between different fluid regimes during the evolution of volatile-saturated granitic and pegmatitic magmas determines the variety of postmagmatic rocks accompanying granite massifs.

This paper presents the first geochemical data on Cr-spinels from ultramafic rocks of the Alkhadyr terrane, which were obtained on a representative collection of samples using modern research methods. The compositional data on melt inclusions allowed the identification of three generations of Cr-spinels on the basis of their morphology, composition, and relationships with the rock-forming minerals. Different types of geochemical zoning were recognized in heterogeneous Cr-spinel grains. The composition of parental melt and crystallization temperatures of the minerals in ultramafic rocks were derived from the compositional data on Cr-spinels and trapped melt inclusions.

Computer inversion of measurement data based on the equation of particle transport is a topical component of the modern nuclear-geophysical technologies. In this work we have elaborated an approach and iterative methods for this inversion according to the gamma-gamma method data. In the framework of the “successive approximations by characteristic interactions” approach, typical interactions have been established and iterative methods for the solution of two problems have been elaborated, namely, the problem of evaluation of the formation density and the problem of evaluation of two parameters - the formation density and the mud cake thickness. The numerical experiments confirm the theoretical concepts of the properties of iterative processes and convergence of methods.

Toxic element distribution in ash-and-slag wastes from the fuel-and-energy complex of the enterprises of Kemerovo Region was studied. The mobile species of copper, nickel, zinc, lead are revealed to migrate into the groundwater. It is demonstrated that the ash-and-slag wastes in the case of contacting with water become a source of toxic elements (vanadium, molybdenum, arsenic, nickel, zinc, manganese and chromium). The content of these elements in groundwater in the territory of ash-and-slag dumps and adjacent natural water sources significantly exceeds the maximum permissible concentration thereof in water.

The results of experiments on DTGA of black coal from the Tavantolgoy deposit (Mongolia) are presented. It was discovered that intense voluminous expansion and at the same time agglomeration of coal material occur during thermal decomposition. This process is accompanied by the removal of gaseous, low melting and boiling components of coal. The effect of preliminary mechanical activation and its duration on the character of separation of thermolysis products was demonstrated. The suitability of coal without additional binding additives for briquetting was established.

Thermolysis of brown coal from the Baganur deposit (Mongolia) was studied. It was established that this coal is distinguished by the high content of gaseous component (up to 40 %) and low content of the liquid fraction (up to 7 %). The decomposition of the material starts at a temperature of about 200 °С. Within the whole heating temperature range (up to 650 °С) the material does not get agglomerated; the final product of thermolysis is loose graphite-like material.

Direct and indirect methods for studying the gas content of coal seams are considered. Advantages and disadvantages of volumetric, gravimetric and dynamic methods are demonstrated with respect to the estimation of potential methane content.

An elemental composition inherent in the ripe fruits of the Siberian sea buckthorn (Hippophae rhamnoides L. ssp. mongolica Rousi) endemically growing in West Siberia was studied. By means of X-ray fluorescence analysis with the use of synchrotron radiation, a quantitative content of K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Y, Zr, Nb, Mo, Pb in the fruits of sea buckthorn and in the soil, as well as biological absorption coefficients for these elements were determined. It has been found that sea buckthorn fruits accumulate titanium, niobium, chromium, zirconium at relatively high quantities with respect to averaged over-ground phytomass, whereas they accumulate manganese, cobalt, vanadium, calcium, lead, strontium, copper, rubidium, scandium, and zinc at relatively low quantities. It has been established that the fruits of sea buckthorn do not concentrate toxic chemical elements such as lead and arsenic.