No 2 (2025)

Research of seismicity migration provide insight into the physical mechanisms of tectonic stress transmission and new opportunities for hazard assessment and prediction of various natural disasters associated with recent geodynamic activity. The review briefly presents the main results of studies of seismicity migration and the fundamental problem of tectonic stress transfer, obtained at the Institute of Tectonics and Geophysics, Far Eastern Branch of the Russian Academy of Sciences in the last decade.

The article presents the results of the application of the probabilistic and statistical method of forecasting the prospects of oil and gas-bearing areas in the waters of the Sea of Okhotsk. The method is based on the use of a preliminary analysis of statistical series of several different types of geological and geophysical parameters. The object of the study of this article is the local concentric structures in the waters of the Sea of Okhotsk. The subject of this article is the forecast of oil and gas bearing areas. The results of using a probabilistic statistical method for predicting the prospects of oil and gas-bearing areas for four types of different geological and geophysical data (crustal thickness, lithosphere thickness, sedimentary rock thickness, heat flux values) measured within the location of fifteen local concentric structures in the Sea of Okhotsk are considered. Based on these data, statistical histograms of the spatial distribution of the values of the thickness of the earth’s crust, the thickness of the lithosphere, and the values of heat flux were previously constructed according to measurements in the main oil-producing regions of the Okhotsk, Black, and Caspian Seas. As a result, using the probabilistic forecasting method, the values of the probability distribution densities were calculated according to the data of various four geological and geophysical parameters. According to the calculated probability values for fifteen concentric structures of the Sea of Okhotsk, according to four types of geological and geophysical parameters, a summary data table was compiled and eight local concentric structures promising for the search for new oil and gas fields were identified.

The objective of this work is to study the interannual variability of lithodynamic and biogeochemical characteristics of suspended matter (SPM) along the 884 km transect “lower reaches– estuary of the Amur River in the Sea of Okhotsk and the Sea of Japan”. Observations were carried out in mid-June 2005 and 2006. The spring flood during the study periods differed dramatically in water content and conditions for mobilization of terrigenous material in the catchment area. Thus, the phases of the culmination of the highest flood level (2005) and the culmination of the lowest low-water level of the Amur were covered. The distribution of SPM, suspended organic carbon (POC), total nitrogen (TN), carbon isotopes (δ¹³C) and nitrogen (δ¹⁵N) were studied. We did not find any sharp fluctuations in the SPM content in the lower reaches of the Amur in 2005 and 2006. However, they manifested themselves in the marine segments of the transect – in the Amur Estuary, in the Sea of Okhotsk and Sea of Japan segments of the estuary. The primary cause of the changes were the physicochemical transformations of SPM against the background of increasing salinity and wave remobilization of bottom sediments. The latter was most clearly manifested in 2006, when the water level in the river segment of the estuary and in the Amur Estuary was low.

In the article, analysis of aircraft observations for atmospheric turbulence on the territories of Eastern Siberia and Russian Far East from January, 2020 to July, 2024 is presented. Observations have been divided by seasons, geographical areas, vertical layers and intensity. The majority of turbulence observations reported from the layers of the upper part of troposphere. Turbulence observations, in the lower part of troposphere, principally, fixed in the planetary boundary layer and showed moderate and severe turbulence near main airports of the region under consideration. Possibility to define type of turbulence based on aircraft, surface and satellite observations and numerical modeling is discussed.

The review proposes a generalization of ecological and genetic approaches to problems traditionally considered within the framework of mathematical population biology. This approach is not the only possible one, but it seems to us original and promising, since сombining mathematical models of natural selection and population dynamics allows identifying possible mechanisms for the emergence of a complex temporal organization of genetic biodiversity very sensitive to external influences. When taking into account the age structure of populations in models, a multimodality appears, which not only makes it possible to explain the change in the dynamics mode, but also to take a fresh look at general biological ideas about existing patterns in population dynamics. Scenarios for the microevolution of the genetic composition of a population that arise with fluctuating numbers allow to explain and describe the pronounced genetic differentiation of individuals of different generations in populations with a seasonal pattern of reproduction; for example, the origin of differences in genetic structure among successive generations of Pacific pink salmon Oncorhynchus gorbuscha. Such models explain litter size polymorphism well in different (natural and artificial) populations of Arctic foxes Alopex lagopus; as well as the emergence and cessation of fluctuations in the numbers of several rodent species, which have recently been observed in many northern populations of Western Europe (for example, the disappearance of population cycles of voles in a number of populations in Finland and Sweden). The identified features of the dynamic behavior of such systems are important from the point of view of the revision and development of established theoretical concepts, since in such systems the principle of simple combination (superposition) of the results of two models is violated: density-independent natural selection of the best genotypes and density-dependent regulation of population growth; modes appear that were not observed separately in each of the models.

Light is an important environmental factor that regulates the accumulation of micro- and macroelements and organic acids in tomato fruits. The use of LEDs for lighting during the growth and development of tomatoes is an effective method for improving the quality of tomato fruits. In this study, LED light sources with a combined spectral composition and high-pressure discharge lamps were used to grow tomatoes in a climate chamber. Using capillary electrophoresis, the mass fractions of cations (ammonium, potassium, sodium, magnesium and calcium ions), anions (chloride, nitrate, sulfate and phosphate ions) and organic acids were determined. It has been established that the type of light sources and the spectral composition of optical radiation are one of the key factors in improving the quality of tomatoes. When grown under LEDs, the concentration of malic acid in tomato fruits increased by 60%, succinic acid by 2 times, and magnesium by 14% and calcium by 57% compared to the fruits of tomato plants grown under gas-discharge lamps. Thus, by selecting the spectral composition of optical radiation, it is potentially possible to increase the content of target components and improve the taste of tomatoes.

The crystal structures of tetrachloride complexes of uranyl with cations of alkali metals, and ammonium, protonated cations of organic bases, ammonium derivatives and a number of protonated organic compounds studied by single-crystal X-ray diffraction analysis are systematized and discussed. The crystal chemical features of the structure of this class of compounds have been determined. In the investigated crystal structures of UO₂²⁺ tetrachloride complexes, the coordination polyhedron of the hexavalent uranium atom has a tetragonal-bipyramidal (distorted octahedral) structure with oxygen atoms of the uranyl group located at the apical vertices of the tetragonal-bipyramidal polyhedron. The UO₂²⁺ groups in the coordination polyhedra are directed perpendicular to the equatorial plane, at the vertices of which four Cl atoms of coordinated ligands are located. In the presence in the structures of uranyl tetrachloride complexes, along with complex anions [UO₂Cl₄]^2– and protonated cations, free Cl^– ions and free, not associated with the U atom, neutral or coordinated molecules, containing acceptor atoms, the cations do not interact with the donor atoms of the Cl^– anion, and form hydrogen bonds with the free chlorine ions and acceptor atoms of the free molecules. Due to the high symmetry (almost D_4h) of the complex anion in the structures of tetrachloride complexes of uranyl, the compounds have been widely used for numerous physical studies, in particular spectroscopic, luminescence, functional density theory and others.

The article examines the main historical stages and chronology of cooperation between the Far Eastern Branch of the Russian Academy of Sciences and the Vietnam Academy of Science and Technology (VAST). The main areas of cooperation are analyzed, examples of joint scientific research, expeditions, programs and projects are given.