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The Aeronian clastic sediments in the Gorny Altai area bear signatures of past seismic effects (paleo-seismites). Sedimentary structures produced by brittle deformation (breccias) span the level of the upper convolutus graptolite zone and the lower sedgwicki zone. They coexist with soft-sediment deformation structures (SSDS), such as turbated and rolled layers, bumpy layer boundaries, etc. At the final deposition stage, the rocks were deformed during seismically-triggered landsliding and were shed into a submarine canyon, with formation of rolls (pseudo-conglomerate).

Studies of the mineral-petrographic and geochemical compositions of high-potassic lamprophyric dikes of the Tobuk complex, manifested at the Ryabinovyi plutonic massif (Central Aldan Mesozoic magmatic province, Russia), have shown that these dikes compose a single fractionation series formed from a high-Mg lamproitic parental melt in an intermediate chamber. The composition of the rocks ranges from olivine-diopside-phlogopite and diopside-phlogopite lamproites through minettes to microsyenites and syenite-porphyry. Early crystallization of high-Mg olivine and chromite in an intermediate chamber could produce cumulative dunites similar to those of the Inagli intrusion. Crystallization of olivine and chromite was followed by cotectic crystallization of olivine and clinopyroxene, then that of clinopyroxene and phlogopite, and, finally, eutectic crystallization of Na-rich clinopyroxene, phlogopite, and K-feldspar. Crystallization and gravitational differentiation of lamproitic melt was complicated by silicate-carbonate immiscibility, which is texturally manifested in minettes as carbonate-silicate globules and interstitial calcium and magnesium carbonates. Furthermore, compositional zoning of Sr in apatite and Ba in phlogopite and K-feldspar is considered to have resulted from the immiscibility. Separation of the carbonate-fluorite melt fraction might have led to formation of the carbonatite and fluorite-carbonatite schlieren and gangues which have been described in drill cores from the Ryabinovyi massif. In most of the geochemical and mineralogic features, the Ryabinovyi massif lamproites are similar to the low-Ti lamproites of the Mediterranean postcollisional belt and northern Vietnam and differ from typical high-Ti within-plate lamproites.

The best source of information about the specific features of magmatism in collision zones is the late collisional tectono-magmatic stage, which is associated with the largest volume and diversity of the resulting magmatic associations. In this paper, granitoid and mafic late collisional magmatism is considered using the example of Early Caledonian igneous complexes of Western Sangilen (Tuva-Mongolian massif). Results of geochronological, petrographic, petrogeochemical, and mineralogical studies of the rocks of the Saizyral mingling dike and salic dikes are presented. Approximately ~485 Ma, high-potassium granitoid massifs formed simultaneously with the intrusion and occurrence of a complex of granitoid and mingling dikes. The Saizyral mingling dike resulted from the joint intrusion and mixing of basic and silicic magmas in a low-pressure region within the Erzin shear zone at a middle crust depth level. Interaction of contrasting magmas is comprised of two stages. The first stage occurs during the transport of a contrast mixture and comes down to intensive mechanical mixing and the introduction of LIL and HFS elements, as well as Th and U from granitoids into the mafic rocks. This changes the geochemical characteristics of the mafic rocks. The second stage is when the joint crystallization of magmas is accompanied by gravitational sedimentation of denser mafic magmas and the formation of narrow zones of intermediate composition at the contact of contrasting rocks.

The results of comprehensive studies of terrigenous rocks of the Khabarovsk Sikhote-Alin accretionary complex are presented. It is established that the fragments of Jurassic and Permian-Triassic sandstones are dominated by poorly rounded and poorly separated material mainly from local provenance areas. The detrital part of the rocks is mainly represented by quartz, in a smaller amount by feldspar and rock fragments. Sandstones are characterized by high silica content, moderate alumina content, low concentrations of femic elements and calcium, moderate alkali content with significant varia-tions in the K/Na ratio. Both Jurassic and Permian-Triassic rocks are typically characterized by reduced contents of LILLE, REE, to a lesser extent HFSE and negative values of the ɛ_Nd(T) parameter - compared to PAAS. The model Nd age of Jurassic sandstones varies from 1.36 to 1.71 Ga, Permian-Triassic - from 1.14 to 1.35 Ga. Most of the detrital zircon population is of late Paleozoic-early Mesozoic age, approximately 25% are older (pre-Paleoproterozoic). The studied sandstones are mainly rocks of the first cycle of weathering (petrogenic), formed during the erosion of igneous rocks of felsic composition. The synthesis of the obtained data suggests that the main source of the cluster material for the Mesozoic sedimentary rocks was the geological formations of the northern part of the Bureya-Khanka superterrane (Bureya and Malokhingan blocks), as well as, possibly, the east-ern part of the Mongol-Okhotsk belt. The Khabarovsk terrane has not drifted significantly along the Tan Lu stike-slip system and is an “autochthonous” block in the present-day struc-ture of Sikhote-Alin.

Direct numerical modeling is used to study the effect of wall heating on the characteristics of reverse wall flow that occurs during turbulent flow of various coolants in a channel with a square cross-section. The temperature field is considered both in the passive impurity approximation and in the low Mach number approximation. Qualitative and quantitative results were obtained characterizing the probability of the occurrence of reverse wall flows in all considered cases at the Reynolds number Re = 3150, calculated from the average flow velocity and half-height of the channel. It has been established that in the considered cases, heating of the walls leads to an increase in the probability of the formation of reverse wall flows by an average of 2-3 times.

Using previously obtained analytical formulas for the natural frequencies and vibration modes of inhomogeneous rods with a variable cross-section (corset shape), the geometric and elastic characteristics of the samples were determined, and the amplitudes of axial stresses obtained during experimental studies of the fatigue strength of metal alloys under high-frequency cyclic loading were assessed. Based on a three-mode model of fatigue failure, a numerical method is proposed for calculating the kinetics of damage under high-frequency cyclic tensile-compression loading of corset-shaped specimens at different values of the cycle asymmetry coefficient. The results of calculations using the proposed model are compared with the results of experiments on corset-shaped samples made of titanium alloy. The proposed model and calculation method make it possible to construct fatigue curves with sufficient accuracy for various cyclic loading modes and cycle asymmetry coefficients. To do this, it is enough to know the base points of the bimodal fatigue curve for the reverse cycle.

Nonlinear vibrations, buckling, and aeroelasticity of a thin nonlinear orthotropic composite plate have been analyzed. The types of symmetric and antisymmetric sheet layering, the number of layers, the fiber angle ranging from 0 to 90°, the effect of constant and variable thermal loads, the temperature dependence of the specific heat coefficient and the elastic modulus of the material, along with the local geometrical defects have been investigated. Using Galerkin's weighted residual theory, partial differential equations have been transformed into nonlinear ordinary differential equations, which are solved by the Runge-Kutta method.

The heat conduction equation of the coupled dynamic theory of thermoelasticity is considered. An assessment is made of the connectivity in the heat conduction equation for a space with a constant initial temperature, containing a flat semi-infinite crack moving at a constant speed, on the sides of which a constant temperature is instantly established, less than the initial one (thermal shock). The movement of a crack and thermal shock on its shores determine dynamic effects that must be taken into account to assess connectivity in the thermal conductivity equation. It is shown that, under real conditions of thermal impact on massive bodies with cracks, dynamic effects and cohesion for materials that satisfy certain conditions imposed on their thermomechanical constants can be neglected, which makes it possible to significantly simplify the solution of problems of thermoelasticity for such bodies.

The problem of forced bending vibrations of a rod-strip with two consoles and a fixed section of finite length on one of the front surfaces is solved. To describe the processes of deformation of consoles, the Timoshenko model is used without taking into account transverse compression and a fixed section - the same deformation model taking into account transverse compression, modified by taking into account the presence of a fixed fixed section. The conditions for the kinematic coupling of the consoles and the fixed section are formulated. Based on the Hamilton-Ostrogradsky variational principle, the equations of motion and boundary conditions, as well as the force conditions for the coupling of sections of the rod, are formulated. Exact analytical solutions of the equations of motion under the influence of a harmonic transverse force at the end of one of the rod consoles are obtained. Numerical experiments were carried out in which the passage of resonant vibrations through a fixed section of finite length in rods made of duralumin and fiber composite was studied, with and without taking into account the transverse compression of the fixed section. A significant increase in the vibration amplitude of the end of the unloaded cantilever of a duralumin rod was discovered due to transverse compression of the fixed section. For a composite rod, the vibration amplitude increased slightly.

The results of experimental measurements of the flame temperature in the presence of an impact surface and a liquid phase added to the flow are presented. Methods based on laser-induced fluorescence were used to measure temperature. For a flame of a pre-mixed methane-air mixture with values of the stoichiometric coefficient Φ = 0.92 and Reynolds number Re = 1000, a reverse flow zone was detected near the impact surface in the case when this surface is located at a distance from the nozzle exit equal to three calibers. The temperature field of a gas-droplet flame was measured using the laser-induced fluorescence method