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The Noion-Tologoi polymetallic deposit corresponds to the Akatui type of polymetallic deposits of eastern Transbaikalia. These deposits are associated with volcanoplutonic rocks of the Akatui complex. In element contents the polymetallic ores of the Noion-Tologoi deposit are similar to ores of volcanohydrothermal (VHMS type) deposits of southern Siberia. The orebodies are tabular, stockwork- and vein-like. They are localized in fault zones. The ores contain, on the average, 4.9% Pb, 6.8% Zn, and 272 ppm Ag. The most common ore minerals are pyrite, galena, arsenopyrite, and sphalerite. The δ¹⁸O (SMOW) values in the ore quartz range from -3.9 to +10.6‰. The isotopic composition of oxygen in the fluid (at 250-275 ºС) varies from -12.80 to +2.79‰, indicating the participation of meteoric waters in mineralization. The enclosing rocks are the volcanoterrigenous deposits of the Mulino Group (J₂-₃) and syenite porphyry of the Akatui complex (J₂-₃). In geochemical characteristics the syenite porphyry is similar to adakite intrusions. The Rb-Sr isotopic age of syenite-porphyry is 150 ± 9 Ma. The initial ratio of strontium isotopes in these rocks is (⁸⁷Sr/⁸⁶Sr)0 = 0.70698 ± 0.0004, which indicates their mantle-crustal source.

The Afontova Gora II archaeological site located within two geologically and geomorphically different areas has been studied in terms of geology and Quaternary deposition history. Both areas lie upon alluvial terrace II of the Yensei River. At the time when terrace I alluvium was deposited, aeolian and slope-wash facies accumulated on the surface of terrace II and a slope-wash apron formed on the gently sloping surface of terrace III. It is at these different levels of the Yenisei River bank that the latest Paleolithic Afontov culture of Siberia has been found. At the Late Glacial-Holocene boundary, the slope-wash apron upon terrace III was involved in landsliding and thrust over terrace II, which deformed the subaerial deposits over both terraces II and III. As shown by detailed analysis, the landslide deposits are either strongly deformed to the degree of losing of their primary sedimentary textures and structures or form imbricated blocks with deformed margins but minor deformation in their interior. The preserved textures and structures of sediments inside the imbricated landslide blocks provide stratigraphic and genetic constraints and prove the in situ origin of anthropological, archaeological, and paleontological finds. This division also explains the archaeological sterility and abnormal thickness of the subaerial cover upon the landslide blocks.

Morphostructural modeling of the block structure of part of the Scandinavian crystalline shield has shown that the ring structure of the Siljan Ring impact crater is located in the center of a morphostructural node, a ring structure with a diameter of 300 km, marking a large disjunctive knot. The crater area consists of a central block, which is a granite massif, and of a surrounding mobile morphostructural boundary forming a wide small-block ring depression zone, where oil and gas shows have been revealed. This zone is regarded as the most promising one for the search for migration channels and atypical shows of hydrocarbons.

The Bathonian Stage in the Sokur Tract section on the periphery of the city of Saratov (Central Russia) contains both Tethyan and Boreal fossils. This makes the section a key object of research aimed at solving the problems of detailed correlation of the Bathoman between different paleobiogeographic provinces and calls for integrated studies involving both paleontological (based on different groups of fauna) and physicochemical (paleomagnetic and isotope-geochemical) methods. The results of study of carbon isotopes in belemnite (Cylindroteuthididae) rostra from the Sokur Tract section show that the Subboreal Oraniceras besnosovi Zone and Boreal Arcticoceras harlandi Subzone are correlated with the standard Zigzag Zone, whereas the Boreal A. ishmae Subzone is totally or mostly comparable to the standard Tenuiplicatus Zone. We have recognized analogs of the chrons of the geomagnetic-polarity time scale (GPTS): e-Bath N, M-Bath R, and lt-Bath N, corresponding to the Lower-Middle Bathonian and, possibly, lower Upper Bathonian.

The seismic effective quality factor ( QC ) and its frequently dependences or the frequency parameter ( n ) and attenuation coefficient (δ) for the Earth’s crust and upper mantle of the North Tanzanian divergence zone (East African rift system) were estimated from an analysis of the earthquake coda waves recorded in the SEISMO-TANZ’07 French-Tanzanian seismic experiment. The QC values increase and the n and δ values decrease with increasing frequency and length of the lapse time window. This behavior of the attenuation parameters may be evidence that the degree of heterogeneity of the lithosphere decreases with depth. Comparison of the depth variations in the attenuation coefficient δ and the frequency parameter n with the velocity structure of the region shows that there is a distinct change in the behavior of seismic wave attenuation at velocity discontinuities. The obtained attenuation parameters were compared with the same parameters obtained in our previous studies for other continental rift systems - the Baikal rift system (Eurasia) and the Basin and Range Province (North America).

This paper presents the results of physical and mathematical modeling performed to evaluate the potential of transient electromagnetic sounding in areas of salt-dome tectonics. Two geoelectric arrays are considered: an array with an inductive source (a horizontal loop) and an array with a mixed-type source (a horizontal current line). It is shown that the transient electromagnetic method provides important information on the relief of the top of salt deposits.

A setup with free oscillations containing a transverse sting for holding the test model and possible test regimes are described. The method of testing and data processing is presented. Aerodynamic characteristics of the pitching moment of the model in a wide range of Mach numbers are obtained. Comparisons of quasi-steady data with numerical predictions and of damping derivatives with those obtained previously in tests of the model mounted on the base sting and with calculated results are performed. The model is found to be statically and dynamically stable except for regimes with М = 1.75 and 2.25, where nondecaying oscillations are excited.

The flow past an axisymmetric body with laminar boundary-layer separation in a low-velocity air stream has been studied. The hot-wire technique was employed to identify the variation of velocity field induced by a local stationary perturbation of separation region at the stern of the experimental model. A large-scale influence upon the near-wall flow due to a cylinder roughness element provided on the model surface was observed. The obtained data substantiate the possibility of controlling the laminar boundary-layer separation on an axisymmetric body using a local external forcing.

Direct numerical simulations of linear and nonlinear stages of the evolution of unstable disturbances of various modes and initial stages of the laminar-turbulent transition in the boundary layer on a flat plate at the freestream Mach number M = 6 are performed on the basis of full unsteady Navier–Stokes equations for a compressible gas. A considerable effect of three-dimensional unstable disturbances on initiation of the laminar-turbulent transition is demonstrated.

The work studies the flow characteristics in a channel with periodic hills on the basis of three algorithms for calculating the flow velocity fields through the images: Particle Image Velocimetry, Particle Tracking Velocimetry, and Pyramid Correlation. Descriptions of algorithms, detailed information about the experiment and parameters of the received data processing, as well as the results of calculations of instantaneous velocity fields at selected time points obtained by corresponding methods are provided. In addition, the presented techniques are compared on the basis of experimental data.