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The general evolution of planets in the Solar System is discussed with a focus on the structure and history of Venus compared with the Earth. The history of the planets of the terrestrial group has been similar and included at least six correlated stages. Many common features the terrestrial planets shared in their early and late evolution have been due to their common origin from the protoplanetary gas-and-dust nebula and plume magmatism widespread on all the planets of the terrestrial group. The characteristic features of the structure and evolution of Venus are most brightly manifested in the specific composition of its atmosphere and of plume magmatism. Venus, with its surface as hot as 450 ºC and the near-surface pressure of 92-93 bars, has a hot and dense atmosphere 93 times that of the Earth in mass. Most of its atmospheric mass (99%) belongs to the 65 km thick troposphere consisting of CO2 (96.5%) and N2 (3.5%). The upper troposphere includes a 25-30 km thick cloud layer composed mainly of sulfuric acid droplets, water vapor, and SO2. At the height of 49.58 km, the clouds approach the conditions of the terrestrial surface and might be hospitable to bacterial life. Volcanism, the most active and widespread process of Venusian geology, maintains continuous SO2 emission. There are diverse volcanic edifices on Venus, which are most often large and are similar to the Earth’s plume-related volcanoes. The evolution before 1 Ga, as well as the share and the role of alkaline rocks and carbonatites among its volcanics, are among the most debatable issues about Venus. Being located closer to the Sun, Venus cooled down more slowly and less intensely than the Earth after the primary accretion. In the Proterozoic, it began heating and reached its present state at ~1 or 2 Ga. In the future, as the Sun becomes a red giant, the Earth is predicted to begin heating up in 500-600 Myr to reach the temperature of present Venus in about 1.5 Gyr.

The Novosibirsk H5/6 ordinary chondrite has signs of shock metamorphism, such as dark shock-melt veins (SMVs) crossing the chondrite host rock. The plagioclase composition grains (Ab78An14Or7) with jadeite were found in the host-rock fragments inside the SMVs. Jadeite has an unusual radial-concentric spherulite-like microtexture. The spherulite-like jadeite formed from the molten plagioclase grain under high-pressure and high-temperature conditions during an impact event. The crystallization was accompanied by Na-K differentiation between coexisting jadeite and residual melt. The PT -conditions of jadeite formation were estimated to be 3-14 GPa and 1400-2150 ºC. Jadeite crystallization, Na-K differentiation, and the pressure-temperature estimates of jadeite formation in the Novosibirsk chondrite are very close to those in the Chelyabinsk LL5 chondrite. The spherulite-like microtexture and jadeite-glass coexistence, most likely, point to a high cooling rate of the SMVs at the pressure release stage of the metamorphic process.

Dendrochronology and radiocarbon dating, with reference to remote sensing, digital elevation modeling, geological, and geomorphological data, provide new age constraints for the Jombolok lava field in the East Sayan Mountains (Siberia). The Jombolok lava field originated in the latest Late Pleistocene and underwent at least four phases of volcanic activity recorded in lava flows. Two earliest phases followed shortly one after another more than 13 kyr ago. The third phase corresponding to eruptions of Kropotkin Volcano can be timed only relatively. The fourth phase has been dated by dendrochronology and AMS 14C of well-preserved wood buried under the youngest lava which occurs among older lavas near the Jombolok River mouth. The age of this activity is bracketed between the death of trees caused by eruptions 1268-928 years ago and the beginning of new tree growth on the surface of the most recent lavas 900 years ago.

We present the chemical and isotope compositions of the water and gas phases of the unique Mukhen cold high- p CO2 spa. Estimated δ18O, δD, and δ13CTIC values and data on the geology and hydrogeology of the studied area indicate that the source of the groundwaters is meteoric waters, whereas carbon dioxide is of deep genesis and numerous regional faults are gas-feeding channels. Calculations of equilibrium reactions in the water-rock system show that the upper-aquifer waters (HCO3-Ca-Mg) with low TDS are undersaturated with carbonate minerals, montmorillonites, and aluminosilicates but are oversaturated with kaolinite, whereas the lower-aquifer waters (HCO3-Na) with high TDS are oversaturated with calcite, dolomite, and clay minerals but are undersaturated with main aluminosilicates. We propose a new concept of the formation of these groundwaters, demonstrating that the long interaction between rocks and groundwaters in the presence of CO2 and the considerable deposition of secondary minerals are responsible for the high TDS of the lower-aquifer waters (up to 14 g/L) and their geochemical type (HCO3-Na) and unusual isotope composition (δ18O = -25.2 ‰, δD = -69.0 ‰).

The mineralogical and geochemical features of the Khoito-Gol ecosystem (fresh thermal waters-microorganisms-travertines) of the Baikal Rift Zone and the aspects of the interaction among its components were studied. The research has shown that the behavior, distribution, and accumulation of trace elements are determined mostly by the geochemical barriers of geologic and biologic genesis in the flowing-water habitat of bacteria of the Khoito-Gol spring. Formation of biominerals by different functional groups of its bacterial community is considered.

Magnetite microspheres from the Carboniferous deposits of the Usolka reference section were studied by probe microanalysis, with comparison of the distributions of chemical elements and microspheres. The presence of microspheres in sedimentary strata is considered an additional factor for stratigraphic correlation between sedimentary sections. The microspheres are shown to be of cosmic nature. The Late Paleozoic paleoclimatic changes (extreme cooling) and biotic crises were caused by the periodical Solar System motion in the Galaxy, cosmic-dust fallout, and meteorite bombardments of the Earth.

Investigation of the Upper Callovian to Lower Kimmeridgian microfossils from the Makar’yev reference section (Unzha River, East European Platform) has been carried out. The section is characterized by ammonite debris and abundant associations of benthic and planktic foraminifera. It is a perfect object for stratigraphic and paleoecological researches. The biostratigraphic distribution of foraminifers from the Makar’yev section allows one to identify standard foraminifer zones of the East European Platform, as well as to upgrade some of them. The analysis of vertical and lateral ammonites and foraminiferal distribution, completed with lithostratigraphy, has precised the stratigraphic volume and position of boundaries of several lithological units. An improved stratigraphic scheme for the Kostroma area of the Moscow Depression is proposed. Analysis of the composition, structure, and dynamic changes of the foraminiferal assemblages has been performed. The morphofunctional analysis of foraminiferal genera has for the first time identified how foraminiferal morphogroups differing in their life style and feeding strategy varied with short-term paleoenvironmental changes. These morphogroup changes allow establishing four ecostratigraphic levels. These paleoecological data have been calibrated along with geochemical factors. They have shown a crisis of foraminiferal association during the Late Oxfordian and Early Kimmeridgian. A similar crisis has also been discovered in the north of Siberia, which may be an argument for its global distribution. The analysis of the taxonomic composition and the density of foraminiferal associations, in parallel with the structure of the association, has revealed a succession of transgressive and regressive events during the Late Callovian-Early Kimmeridgian. It allows the typification of each assemblage in relation with each event and underlines the occurrence of second-order sea level changes (middle Middle Oxfordian and the earliest Kimmeridgian).

We discuss the results of studying the physical-chemical composition of the atmospheric aerosol during expedition onboard RV “Akademik Nikolaj Strakhov” carried out during winter of 2015/2016 on the route from Colombo to Kaliningrad (via Suez Canal). In comparison with the Mediterranean Sea and Atlantic (near Europe), the atmosphere of the Arabian and Red Seas was characterized by higher values of most aerosol characteristics: 3-5 times larger aerosol optical depth (AOD), 4 times larger aerosol number concentration, 1.5 times larger concentrations of continent- and sea-derived ions, as well as more abundant gaseous admixtures (SO₂, HCl, HNO₃, NH₃). At the same time, two seas of the Indian basin show substantial differences in aerosol composition, caused by outflows of aerosols of different types from the continents. The largest concentrations of black carbon (2.14 µg · m^-3, on the average), sea-derived ions (Na⁺, Cl^-, Mg²⁺), and NH₃ are observed over the Arabian Sea; and larger values of fine component of AOD and concentrations of “continental” ions (SO₄^2-, Ca²⁺, NO₃^-, NH₄⁺) and gaseous admixtures SO₂, HCl, HNO₃ are found over the Red Sea. With respect to ion composition of aerosol, most stable concentrations are noted in Ca²⁺ ions (less than 15% difference among the seas), and maximal spatial variations are found in NH₄⁺ ions (a difference is up to a factor of 40).

Created in Russian space observatory Millimetron with a 10-meter optical telescope has no analogues to solve scientific and technical tasks of research objects in the Universe. The amount of information that can be obtained at this observatory largely depends on the chosen concept and manufacturability of technical means that implement a high image quality in the telescope. The article, based on the analysis of distorting factors, examined ways of possible technical solutions and concepts, which can be the basis for the creation of systems of adaptive correction of the wavefront distortion (WF) of the received radiation. Variants of adaptive space telescope optical system are considered and analyzed. Following the results of analysis the adaptation at the entrance pupil of the telescope is selected and substantiated, are realized by a circuit of parallel information reading petals of the compound main telescope mirror.

New method for wavefront reconstruction from measured gradients is proposed on the basis of the solution of variational problem. Spatial frequency transfer function is obtained for its reconstructor. Accuracy of the restoration is studied, by methods of numerical modeling, at different spatial spectra of wavefront distortions. Reconstructor sensitivity is analyzed in the case of data loss in some nodes of measuring grid.