The results of density modeling of the structure of the tectonosphere through the Antarctic sector of the South Atlantic Ocean along profiles stretching from the Falkland Plateau to the Mozambique Ridge and crossing a series of uplifts and ridges separated by deep-sea basins are presented. Studies have shown that the crust of this region has a heterogeneous structure, and the uplifts have a different structure of the crust, which indicates their different origin.

We jounded traces of 2 earthquakes of the 10th and 12th centuries were found at 6 objects of the Afrasiab archaeological site, which include numerous faults and fractures that form a “flower” structure, a subsidence graben, slopes and turns of fragments of fortress walls. Judging by the nature of the deformations, the epicenter of the earthquake of the 10th century was located to the west-southwest of the ancient city, and the epicenter of the earthquake of the 12th century. — to the south-southwest of it. The intensity of both events was VIII–IX points on the scale MSK-64.

Verkhnyaya Lena formation (Є_2–3vl) was studied in the section on the right bank of the Malaya Chuya River. The concentrations of main oxides and some trace elements (Cr, V, Ni, Cu, Zn, Rb, Sr, Zr, Ba, U, Th, Y, Nb, Cl) were determined in the samples using X-ray spectral fluorescence analysis (XRF). Based on the results of XRF, the standard mineral composition was calculated using the MINLITH. Geochemical data clearly distinguishes intervals of changing weathering characteristics (physical/chemical, arid/humid) in the denudation area, which are fixed by variations in the values of the Al₂О₃/K₂О ratios, Ln (Al₂O₃/Na₂O), contents of V, Cu, Zn, Rb, and Ni, as well as normative mineral composition. Cr, apparently, was transported exclusively by the aeolian process and marks periods of increased wind transport intensity. Under the conditions of tectonic activation and progressive isolation of the paleobasin, the lithological and geochemical features considered provide some information about the climatic changes that accompanied these events.

The article considers the results of a comprehensive study of the Lower-Upper Ypresian boundary deposits of the mount. Suvlu-Kaya section (Bakhchisarai region, Southwestern Crimea). On the basis of a detailed microfacial analysis, the evolution of a nummulitic bank formation of the studied area is shown. The sediments were formed on a deep shelf with depths at and below the storm wave base. Three stages of the Ypresian transgression are shown, it was developed gradually with a maximum at the end of the Early Ypresian, then replaced by a prolonged regression. The data are confirmed by the results of micropaleontological morphogroup analysis.

The data of magnetic properties and composition of chemical elements were obtained in the stratotype of Belogrodni formation (Danian stage) and it there was made their cyclostratigrapic analysis. By the results of Fourier transform of vertical subsequences of petromagnetic and geochemical parameters in the section there were identified the cycles, corresponding to the periods of long and short eccentricity of Earth orbit. The sedimentation time of studied section was estimated as (~2.1 myr), and the rate of glauconites sedimentation was estimated as (~1 cm/kyr).

 In this work, the geochemical and lithological features of bacterial-algal structures from the top of the Abalak and Georgian Formations in the central part of Western Siberia were studied in order to determine the specific conditions of their formation. The authors compared the element composition of these microbial carbonates with the secondary carbonate rocks of the Abalak and Georgian Formations. According to the results of X-ray fluorescence analysis, differences were identified in the contents of MnO, Cr, V, Ni, Cu, Zn in two types of carbonates. The higher content of MnO in bacterial-algal structures were explained by the ability of bacteria to sorb Mn on the surface of their cells. This process requires oxygen, which suggests the presence of a natural aerobic environment for the development of bacteria during the period of sediment accumulation. According to the results of the study of microbial carbonates under a scanning electron microscope, it was revealed that Mn, for the most part, is concentrated in carbonate minerals, in particular in kutnohorite. The increased content of biophilic elements such as Ni, Cu, Zn, V in microbial carbonates is probably associated with the transformation of humic organic matter, that was accumulated in shallow water environments and was actively recycled by microbial organisms. Minerals with the high Ba concentration were also found in isolated bacterial-algal structures. According to the authors, such single barium mineralization could be caused by the point effect of both near-surface and deep-seated barium-containing solutions and are not associated with an increased content of manganese in the studied deposits.

The paper presents the results of studies of the lithological-facies composition and paleogeographic environments of the formation of the main oil and gas complexes in the northeastern part of the Sakhalin shelf. Based on the results of core studies, an assessment of the reservoir and screening properties of the rocks, which make up the Lower Miocene stratigraphic complex, was carried out. The data on the lithological composition of reservoirs, the nature of cement and the composition of seals for 12 deep exploration wells drilled on the shelf are presented. The studies carried out made it possible to predict changes in the lithological-facies composition and reservoir properties of the rocks that make up the main oil and gas complexes. There are 3 categories of zones with different indicators of filtration-capacitive properties.

 A complex of methods (seismoacoustic profiling, analysis of continuous sections of wells, stratigraphic studies on malacofauna, radioisotope age dating) in the composition of Upper quaternary deposits of the shelf of the Northern Caspian, the Novocaspian, Mangyshlak, Khvalynsky, Athelsky, Hyrkan and Upper Khazar horizons were identified. Based on AMS radiocarbon and uranium-thorium dating, the time of their accumulation is determined, respectively, in the intervals 0–8, 8–12, 12–50 (60), 50–70, 80–100 and more than 120 thousand years ago.

This paper presents the results of a detailed petrological study of a continuous section of the Golygin ignimbrite, related to the Pauzhetka caldera-forming eruption (443±8 ka BP). The continuous zoning of the studied sequence suggests that a large magmatic chamber, emptied during the eruption, was also zoned and had significant vertical dimensions. Our research included determining the bulk composition of rocks, studying samples of the Goligin ignimbrites in thin sections, and detailed studying of quartz and melt inclusions in it. The roof of the magmatic chamber was at a depth of about 5 km; amphibole and plagioclase crystalloclasts in rocks at the base of the sequence show evidence of formation in a more basitic melt at a depth of 24 to 25 km. The composition of the magmatic melt reconstructed from melt inclusions in quartz from this sequence corresponds to medium-K rhyolites (wt %): SiO₂ 78.1–77.9, Al₂O₃ 12.7–12, FeO_t 0.8–0.1, MgO 0.1–0.0, CaO 1.0–0.2, K₂O 4.3–3.8, Na₂O 4.9–3.3, Cl₂ 0.1–0.2. Crystallization temperatures calculated for various minerals and their parageneses vary in the range 1009–784°С, which, together with estimates of formation depths of 25 km to 5 km, may reflect nucleation of magmatic melt, its ascent and evolution in a relatively shallow chamber where it was slowly cooled and crystallized. The maximum water content of the magmatic melt during quartz crystallization was estimated at 4.1 to 7.5 wt% H₂O.

The issues of constructing a general classification of geological processes that are the subject of research in modern engineering geodynamics, one of the areas of engineering geology, are considered. A general classification of geological processes for the purposes of engineering geology is proposed, taking into account the shortcomings of previous similar classifications and covering the whole variety of both natural geological processes and their technogenic analogues — engineering geological processes.

We analyze long-term and annual groundwater level fluctuations in the Kamennaya Steppe Nature Reserve in Voronezh Region based on monitoring data from the Dokuchaev pit. This pit is a unique groundwater monitoring site with the longest observation period in Russia and Europe, amounting to 130 years. The specific feature of groundwater formation of the Quaternary horizon, which captures the pit is that the annual and multi-year regime of groundwater levels is determined by the dynamics of infiltration water exchange between groundwater and the surface. The analysis is based on an extensive factual record, including long-term series of hydrogeological observations and meteorological database. A set of methods and approaches was used: statistical methods, correlation analysis, SURFBAL water balance calculations, etc. Cross-correlation analysis of water levels in the pit and other observation wells on the Quaternary horizon revealed that the Dokuchaev pit is a representative observation point to assess the patterns of fluctuations in groundwater levels in the Kamennaya Steppe. Based on the analysis of time series it was found that the observed dynamics of water level in the pit follows the course of the main regime-forming factors — precipitation and potential evapotranspiration, determining the excess or deficit of moisture for infiltration in a multi-year framework. Extreme decrease of water level in the pit to its partial drying in 2020–2022, observed during last 15 years, relates to dynamics of these factors. Based on model studies, it is shown that there is a gradual transformation of annual regime of fluctuations of water level in the pit in the late 20th and early 21st century compared with the mid-20th century due to changes in conditions of spring-winter absorption of moisture from the surface of the earth and the formation of infiltration feeding. However, it is not as significant as, for example, the transformation of river hydrographs in the Don basin.

The paper presents the results of the estimation of the depth temperatures of the warming of mineral waters of the Essentuki field, extracted from four productive (Danish-Zeland, Cenomanian-Maastrichtian, Aptian-Lower Albian and Titon-Valanginian) aquifers by the method of ionic geothermometers. It was revealed that the most adequate depth temperature values with a range of 64–97 °C are obtained with the “silica” geothermometer, while the Na–K geothermometer shows overestimated and the Mg–Li and chalcedony underestimated temperatures. Estimation of the depth of water penetration gives values of 1.2÷1.8 km for waters of the Danish-Zeland, Cenomanian-Maastrichtian and Aptian-Lower Albian aquifers, and more than 2 km for waters of the Titon-Valanginian aquifer.

The studies have been carried out to evaluate two natural clay soils as promising materials for creating safety barriers for radioactive waste disposal. Composition indicators affecting the absorbing properties of clays have been studied. The absorption capacity of soils was studied under dynamic conditions on columns in relation to Cs, Sr, U, Th, Ba (analogue of Ra), Nd and Dy (analogues of Am-241, Cm-244) which may be present in radioactive waste of III and IV hazard classes. The experimentally obtained migration parameters (effective porosity and effective dispersion coefficient, as well as the sorption capacity of the soils) are used in predictive mathematical modeling for a comparative assessment of the effectiveness of safety barriers from the considered materials and the possibility of their usage.