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Using the Selector PC application and a stationary flow reactor, we studied the process of formation of magnesian skarns at the contact of dolerites with carbonate-salt deposits. The physicochemical parameters of metasomatic processes were estimated by studying the localization of skarn ore shoots and mineral assemblages in the deposits of the Angara-Ilim type. The action of magmatic fluids on the system dolerite-magnesian salt deposits and dolerite-carbonate-salt deposits resulted in zonal columns of infiltration magnesian skarns. The computation was carried out using a dynamic multireservoir model of a flow reactor with a constant temperature gradient and a uniform pressure. We have established that changes in the C/H ratio and Cl content in the fluid source affect the composition of the produced mineral assemblages. Depending on the temperature during the formation of skarns, different mineral assemblages are produced: diopside, enstatite, anorthite, quartz, ilmenite, hercynite, and pyrrhotite at 1040-1010 ºC; monticellite, forsterite, magnetite, geikielite, periclase, spinel, calcite, and graphite at 980-740 °C; and calcite, dolomite, phlogopite, halite, and graphite at 710-380 °C. Wollastonite is observed in the rear zone of magnesian skarns. We examined the temperature-dependent sequence of formation of different types of silicates, spinels, and Ti-containing minerals in the metasomatic column. The computation results show that during crystallization, the tholeiitic magma releases a fluid phase with C/H = 0.1-1.0, amounting to 1.5-2.0 wt.%.

Comprehensive studies of mineralogy, fluid and melt inclusions, and gas phase in minerals from a representative collection of peridotite xenoliths that underwent metasomatism and convective partial melting in the mantle wedge beneath Avacha Volcano were used to simulate interactions between mantle wedge material and magmatic fluids of constant and variable compositions at different depths, as well as metasomatic effects of fluids derived from subduction slabs. The obtained virtual dynamic patterns of metasomatic zoning across the mantle wedge show how composition variations of fluids and PT conditions at their sources influence the facies of metasomatized mantle wedge harzburgite. The compositions of the Avacha xenoliths and crustal rodingite from Kamchatka compared with results of physicochemical modeling suggest that eruptions of Avacha Volcano brought metasomatized material of the upper mantle wedge to the surface. The rocks underwent multistage metasomatism along cracks in a relatively narrow temperature range. Such processes are apparently common to seismically deformed permeable lithosphere above magma reservoirs. However, the mineralogical zoning of the Kamchatka crustal rhodingites differs from that in cracked metasomatic peridotite above the sources of magmatic fluids in the mantle wedge beneath the Kamchatka arc.

Modeling of fluid-magmatic systems in a suprasubduction mantle wedge is considered for the case of Kamchatka with reference to data on peridotites from other known subduction and oceanic rock complexes. This modeling has to take account of magma storage in several intermediate reservoirs at different depths, up to six such reservoirs, as in the case of Avacha Volcano. Comparison of available data on melt inclusions in spinels indicates crystallization of the Avacha peridotites in magmatic systems progressively decreasing in temperature (>1200 °C → >1100 °C → >900 °C) and pressure (from 13.8 to 4.5 kbar) in intermediate reservoirs at depths of 30-40 and 15-20 km. The Avacha harzburgites do not belong to primary oceanic mantle as they lack both signatures of high-temperature plastic flow and effects of mantle melts known for sheared mantle peridotites from ophiolite suites. The vP / vS ratio estimated from jointly analyzed P - and S -wave velocities ( vP and vS , respectively), an important indicator for seismic tomographic reconstructions of subduction zones, allows discriminating between regions saturated mainly with liquid (melts) and gas phases beneath volcanoes. Only specially tested tomographic data can provide reliable reference for modeling of mantle wedge processes.

We investigated organic matter (OM) of the Lower Cambrian Sinyaya Formation in the southeast of the Siberian Platform. The studied collection of rocks was divided into groups according to the contents of organic carbon, bitumens, and sulfur and lithologic characteristics. The content and distribution of saturated biomarkers were examined. Lanostanes C30, norlanostanes C29, 28,30-bisnorhopanes, and 2α- and 3β-methylhopanes have been identified in the bitumens. Relationships between the content of organic carbon and the distribution of hopanes, hopane ratios, and 2α-methylhopane index have been established. The conditions of sedimentation, diagenesis, and catagenesis of OM and the generation potential of the rocks have been estimated. It is showb that lanostanes, 28,30-bisnorhopanes, and methylhopanes can be used as biomarkers of the source rocks of the Sinyaya Formation and thus can help to determine the source of bitumens on the northern slope of the Aldan anteclise of the Siberian Platform.

We present results of study of organic matter in the coastal and bottom sediments of the Laptev Sea (Buor-Khaya Gulf). The study has shown the regularities of organic-matter distribution in the shelf zone adjacent to the glacial coast. The coast composed of a glacial rock complex supplies the largest amount of organic material to the sea as compared with other types of the coast. The average content of organic matter in these strata is ~2-3 wt.%. The bottom sediments of the shallow littoral zone are significantly depleted in organic carbon (0.1-0.3%) as a result of their active rewashing and the transition of finely dispersed material (mainly organic one) toward the deep sea zones. The content of organic carbon in the bottom sediments increases to 1-2% as the sea deepens to 7-10 m at 5-12 km from the coast. There are frequent local anomalies of organic-carbon contents (up to 4-5%) in the deltaic zones of the sea. The highest contents of organic carbon (up to 3%) have been found in the recent marine sediments in the central, relatively deep zones of the bays.

The fact that uranium, coal, oil, and other ores occur in the same sedimentary basin has been extensively recognized. By comparing the spatial and temporal relationships among uranium, coal, and hydrocarbons, we found that the ore-bearing uranium and coal layers within the same basin are commonly interbedded or adjacent to each other. In general, however, uranium deposits are spatially distant from oilfields. We analyzed the genetic relationship among oil, coal, and uranium by compiling numerous geological surveys, test analyses, and previous studies of the Ili, Songliao, and other basins in North China. It is considered that the mild and humid paleoclimate should be an important factor affecting the formation of coal reservoir, mudstone as the upper and lower aquifuges, and the host rocks with rich organic matter. Thus, these coal-mining areas occurring at the edges of basins deserve to be studied in detail for uranium exploration. In addition, the metallogenic epochs are roughly similar to the epochs of hydrocarbon migration and tectonic events. These existing data of oil exploration can be used to unravel the regional and local tectonic evolutions of the basin related to uranium mineralization. Finally, a rough relationship between uranium mineralization and hydrocarbons was presented. Note that hydrocarbon is not just beneficial for the formation of uranium deposits but may also inhibit the transportation and mineralization of uranium-bearing materials. Regions with shallow hydrocarbon fields or large quantities of hydrocarbon dissipation are not the ideal exploration locations for uranium.

The paper presents results of 2D mathematical modeling of induced polarization (IP) in the cases of profiling and tomography for piecewise media containing orebodies with different structures, sizes, depths, relaxation times, chargeability, and electrical resistivity. The standard and spectral approaches to data analysis are compared. The cases when analysis of transient IP characteristics yields new information of practical importance are considered. The main features of transient IP characteristics in 2D inhomogeneous media are determined from the modeling results. Analysis of transient IP characteristics yields the best results when the depth of occurrence of polarizable bodies is minimum and their electrical conductivity is an order of magnitude lower than that of the host rock.

Thermal conductivity of R–410A mixture in the vapor phase (314–428 К and 0.1–2.0 MPa) has been studied by the steady-state method of coaxial cylinders. Experimental uncertainties of temperature, pressure, and thermal conductivity measurements did not exceed 0.05 K, 4 kPa, and 1.5–2.5 %, respectively. The approximating equation has been obtained for thermal conductivity depending on temperature and pressure. Thermal conductivity on dew line and in ideal-gas state has been calculated.

Results of experimental studies of electrode erosion in high-current arc discharges are presented. Available data on the service life of electrodes in the arc plasma generators sometimes are contradictory and do not give the whole pattern on the relationship of specific erosion of the electrode material with the basic determining parameters of the plasmatorch. The real ways to increase the duration of plasmatorch operation before electrode replacement have been proposed.

The article considers some aspects of the research methodology of micro heat power plants based on internal combustion engines with air cooling and cogeneration based on energy balance equations and the laws of heat transfer. The research is conducted for such a setup based on the Hitachi internal combustion engine with 2.4 kW capacity. It has shown the efficiency of cogeneration use in the form of useful heat flow from air, cooling the cylinder head, with its further heating by utilizing the heat of flue gases in an additional plate heat exchanger. It has been shown that the cogenera-tion can save fuel costs 3–10 times compared with heat guns, depending on the duration of the setup use.