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It is indicated that surface water resources under the conditions of growing technogenesis and the consequences of military actions (military, geochemical pollution of catchment landscapes, destruction of treatment facilities, etc.) are classified as polluted and dirty (IV, V quality class). Underground water resources of Ukraine amount to 22.5 billion m3, of which up to 70% are protected or conditionally protected artesian waters of drinking quality, the transition to the use of which determines the relevance of the article. The purpose of the article is to analyze the potential factors of regional development of dangerous geofiltration processes of water use in underground water basins of Ukraine. The scientific novelty of the article lies in the assessment of the degree of influence of the complex of dangerous lithodynamic processes (HLDP), which have a hydrogeofiltration origin, on the qualitative characteristics of groundwater, the stability of the upper part of the rock massif, and the safe operation of water intake facilities. Practical significance. It is shown that with any scheme of depression funnel formation, the diffusion-convective movement of salts and microcomponents from the pore solutions of the poorly permeable (separating) layer is a stable spatio-temporal factor affecting the hydrogeochemical composition of water in operational aquifers. It has been proven that the hydrogeochemical evolution of the composition of water at most water intakes in Ukraine requires changes in approaches to the justification of well location schemes and the amount of allowable decreases in levels in operational horizons. It is estimated that engineering-geotechnically significant filtration compression of the aquifer occurs when the level drops by tens of meters or more. The results of spatio-temporal monitoring of filtration and compression subsidence of the earth's surface in the areas of depression funnels of water intakes and drainage and drainage systems of quarries and mines on the territory of Ukraine indicate that, in general, the amount of subsidence of the earth's surface is correlated with a decrease in the level in the operational aquifer, and in in most cases it is 1.0-2.5% of its value. It has been established that the subsidence of the earth's surface in the zones of depressions of underground water intakes is often accompanied by flooding and waterlogging of the territory, deformations of buildings and structures of engineering communications. It is stated that the active role in the development of the suffusion process during the operation of water intakes and drainage systems is played by the interlayering of fissured (crack-karst) sandy, multi-grained aquifers. This contributes to the formation of zones of increased hydraulic gradients and accelerated movement of hydrogeofiltration flow at the contacts of cracked and sand-dust layers and, as a result, activation of suffusion along the cracks. Calculations prove that the dangerous development of the suffusion process in the near-filter zone of the production well on the aquifer in multi-grained sands reaches 10-15 m. In the central zone of the depression funnel of a group or linear water intake, under the condition of the interaction of local well depressions, the distance of the development of suffusion deformations of the earth's surface increases significantly (up to 3-5 times) and worsens the engineering and geotechnical stability of production wells, pumping equipment, etc.

Statement of the general problem. The oil and gas-bearing province of Eastern Ukraine is located in the Dnipro-Donetsk Basin (DDB). It covers the Paleozoic structural floor and is buried under younger sediments. The Paleozoic structural floor of the territory is represented as a long rift graben. The maximum thickness of the sedimentary cover in the graben is 15–17 km. According to geophysical data, the thickness of the earth's crust is 31–32 km under the axial part of the DDB and increases towards the sides. But according to the maximum thickness and facies characteristics of the Paleozoic deposits, the thickness of the Earth's crust below them could not exceed 20 km. The modern thickness is 1.5 times higher. Therefore, such a geological-geophysical model of the structure of the DDB is contradictory. Analysis of recent research and publications. The removal of the contradiction is possible due to the detection of a series of Hercynian thrusts with total amplitude of thrusts of the order of 50 km. Such thrusts began to be established on the northern and southern flanks of the DDB. Hercynian thrusts have a southwestern vergence. In the north, the Voronezh crystalline massif is pushed onto the DDB along the Noviy thrust with an amplitude of 9–10 km. In the south, the South Donbas melange zone is established, which pushes the folded Donbas onto the Ukrainian shield. On its continuation to the northwest is the southern side of the DDB - the so-called Southern monocline. The well-studied Pavlograd-Petropavlovsk coal mining district of Western Donbass with operating coal mines is located within its borders. An unsolved part of the overall problem. Numerous faults with relatively small amplitudes are established within the Paleozoic Southern Monocline. Together, they form a system of horsts and grabens with a north-western extension. But the bottom parts of the grabens are 1–3 km higher than the tops of the horsts. Such a geological situation is anomalous. This indicates the post-fault dislocation of the horst-graben system as a whole. The purpose of the article is identification of the causes of the anomalous structural position of the graben-horst system in the modern geological structure of the Southern Monocline and in the general model of the geological structure of Eastern Ukraine. Research materials and methods. Were involved more than 390 geological sections, constructed based on the data of more than 10,000 wells. Of them, 265 wells revealed the folds that are being analyzed. In addition, were used data of catagenetic transformations of the sedimentary section. Presentation of the main research material. The South Donbas mélange zone falls to the northeast and continues under the Southern Monocline. It is located in the upper block of this regional thrust structure and is in an allochthonous setting. According to geological data, the true amplitude of the thrust of Western Donbas on the Ukrainian shield is 15–20 km, and the vertical component of this amplitude exceeds 3 km. Such spatial parameters explain the abnormality of the structural position of the horsts and grabens of Western Donbass - their southwestern flanks were significantly raised relative to the northeastern flanks during thrusting. Scientific novelty. Therefore, in the modern geological structure, the Dnipro-Donetsk "basin" is not a rift, but a post-rift Hercynian folded region. It is formed by high-amplitude thrusts on the northern and southern flanks. The Hercynian fold region is buried under Mesozoic and Cenozoic sediments and is further complicated by Laramian and Attic fold-thrust dislocations of lesser intensity. Conclusions. The thrust model brings the geophysical parameters into the correspondence with the geological data and is confirmed by the actual material.

Problems Statement and Purpose. This article is a continuation of the authors' previous publications on improving the methodical approach to assessing the vulnerability (protection) of drinking groundwater within the Dnipro-Donetsk artesian basin (DDAB) and is a practical component of these studies. In order to find and develop optimal forms of ecological safety management of drinking water supply for the region population, the authors' improved approach to assessing the vulnerability (protection) of drinking groundwater in the strategically important waters of buchak-kaniv aquifer (BKA) was tested. The purpose of article is the ecological and hydrogeological zoning of research area according to the danger of quality transformation of BKA groundwaters and the determination of zones of increased ecological danger of these waters quality reduction due to elements of surface and deep genesis. Data & Methods. The research is based on the analysis of results of drilling more than 950 wells in this region, as well as about 500 measurements of piezometric levels of BKA and the first interlayer aquifer during 1960-2020. Results. Complex systems of ecological and hydrogeological zoning of the territory of DDAB central part have been developed according to the degree of ecological danger of lowering the quality of BKA drinking groundwater. Zoning of the territory was carried out according to the danger of deterioration of these waters quality by man-made pollutants that enter the waters in the process of downward vertical filtration and migration from the earth surface. Ecologically dangerous areas with a potential decrease in the quality of BKA drinking groundwater due to elements of surface genesis (water intakes of Poltava, Lubny, Myrhorod, Velyka Bagachka, Krasnograd cities and some others) have been identified. Zoning of the territory was carried out according to the danger of deterioration of the BKA groundwater quality due to the upward migration of natural deep substandard waters. Ecologically dangerous areas with a potential decrease in groundwater quality due to elements of deep genesis (water intakes of Poltava, Romodan, Myrhorod, Shyshaky, Opishnia, Gadyach, Krasnograd, Karlivka cities and some others) have been identified. It is recommended to develop measures to increase the ecological safety of the population's drinking water supply: hydrogeochemical monitoring of characteristic indicators of water quality composition and optimization of the powerful water intakes operating modes (within ecologically dangerous territories); creation of new water intakes (within ecologically safe territories).

Formulation of the problem. The paper is devoted to the study of the ecological state of the natural environment components in connection with the impact of technogenic facilities of the Lysychansk-Rubizhne industrial hub. The purpose of the paper is to analyze the technogenic impact of the Lysychansk-Rubizhne industrial hub on the natural environment components. Materials and methods. The natural environment components data including atmospheric air, soil, surface water, groundwater from the Regional Report on the natural environment state in Luhansk region were used and analyzed. The total pollution index was calculated to determine the level of soil contamination in the areas of biggest technogenic impact. The places furthest from the cities with powerful sources of the natural environment pollution are allocated. Mathematical processing of geochemical information was performed on separate samples. The containing of specific chemical elements in the soils of Lysychansk-Rubizhnе industrial hub is calculated. The obtained data were used to calculate the concentration coefficient. The level of chemical contamination of soils as an indicator of adverse effect on public health is determined by following indicators: 1) the chemical substance concentration coefficient (Kc), which is determined by the ratio of its actual containing in the soil (C) to the background containing (Cb); 2) the total pollution index (Zc), which is equal to the sum of the concentration coefficients of chemical elements. Results. As a result of the study, it was found that the territory of the Lysychansk-Rubizhne industrial hub is still under a huge technogenic impact, despite the closure of many enterprises. Abandoned settling tanks, sludge collectors, spoil tips, landfills of various industrial wastes and other are one of the main sources of the natural environment pollution today. The ecological state of the natural environment components (atmosphere, surface water, soil and groundwater) is described in the paper. Quite positive changes are observed only in the situation with atmospheric air. The tendency to reduce emissions of pollutants into the atmosphere is associated with the liquidation of industrial enterprises over the past 20 years. The state of other natural environment components remains unsatisfactory: surface water, soil and groundwater are contaminated with heavy metals, petroleum products, nitrates, nitrites, etc. (the nature of the pollutants depends on the nearby technogenic facilities). It is noted that these technogenic facilities lose their waterproofing over the years, so they are currently sources of pollutant migration to the natural environment. Scientific novelty and practical significance. An integral assessment of the Lysychansk-Rubizhne industrial hub impact on the natural environment components, which allowed us to talk about the different degree of technogenic impact and different influence factors, is the scientific novelty of the study. The different genesis of pollution in the given area is proved. It is established that there is an infiltration from the surface on the left bank and pollution of deep origin on the right bank. The long-term forecasts of changes in the ecological state of the Lysychansk-Rubizhne industrial hub territory are given as practical use of the obtained results. It is proposed to carry out continuous monitoring of the natural environment for a more detailed study of the environmental situation.

Formulation of the problem. The paper is the beginning of scientific papers series of authors on an actual environmental topic – multidimensional system geomonitoring of groundwater in water intakes areas. The purpose of article is a substantiation of application possibility of the method of objects trajectory modeling in the normalized phase space, which has been developed at V. N. Karazin Kharkiv National University for socio-geographical monitoring tasks, for hydrogeological objects geomonitoring. Materials and methods. The research is based on the method of objects trajectory modeling in the normalized phase space. To achieve the purpose of this study, geomonitoring data of five water intakes in Poltava city, which operate Cenomanian-Lower Cretaceous aquifer, has been used. Changes in the average chemical composition of groundwater for each water intake have been analyzed according to 12 indicators: pH, hardness, dry residue, ammonium, fluorine, chlorine, sulfates, bicarbonates, calcium, magnesium, sodium+potassium, ferrous iron. The initial data have been collected from 1981 to 2008 according to an irregular pattern in time (39 points in time). Research results. The following indicators of systemic development of hydrogeological system have been calculated for each water intake: a) for each period of time – the path length traveled by the water intake hydrogeological system, which characterizes the intensity of changes in the groundwater chemical composition; b) for each control time – the projection of current trajectory point on the optimal trajectory (main diagonal), the deviation of point from the optimal trajectory, the progress coefficient (the ratio of point projection to the length of main diagonal). The main trends in the systemic development of hydrogeological system for all studied water intakes have been identified: - the intensity of changes in the groundwater chemical composition at water intakes Nos. 1-5 decreases over time, which can be explained by the reduction of water withdrawal and hydrodynamic factors associated with the formation of depression funnel, in particular the spreading of quasi-stationary filtration regime; - according to the absolute values of changes intensity in the groundwater chemical composition, the water intake No. 3 is highlighted, the value of which is significantly less than the values of other water intakes; - groundwater at the water intake No. 1 has the greatest variability in the changes intensity of chemical composition over time both in amplitude and in absolute values; - there is a very noticeable synchronization of movement intensity graphs of water intakes hydrogeological systems in the normalized phase space and the average intensity of changes in the groundwater chemical composition, but a detailed analysis reveals some deviations from this pattern, which may be due to abrupt changes in operation mode of water intakes.

The article presents the physical and geographical characteristics of the Synychan water intake section of the Izium water intake, which is located 8 km southeast of the city of Izium, Kharkiv region. Hydrogeological features of aquifers operated by 4 wells are considered. Geomorphological features of the studied territory are analyzed. Aspects of the geological structure of the site are also reflected. The analysis of indicators of chemical composition of underground waters of the Synychan water intake site since 2003 is presented. Among the most relevant to the task of chemical compounds, the values of nitrates, chlorides and sulfates content, as well as data on total hardness and mineralization were selected. An increase in performance is observed in all wells. The intensity of the increase is different for each production well and the corresponding chemical compound. This indicates at least the heterogeneity of influencing factors and processes occurring in the aquifers of this water intake area. Among such factors and processes, taking into account the shallow depths of wells, we can consider the technogenesis. Since Synychan water intake is used to supply a significant number of residential areas of Izyum, a detailed analysis of the dynamics of the presented data is appropriate. The study of the dynamics of the distribution of chemical indicators of groundwater composition over different periods using mathematical and graphical methods will not only allow to inductively study the dynamics in previous years, but also quantitatively predict future trends in water composition of interstratal aquifers in the region. Considering the growing and growing shortage of quality water resources in Ukraine, the analysis of data from water intake areas of Izyum can give a representative picture of the real local situation in the field of water management, hydrogeology and hydrogeochemistry of Izyum district in general and town of Izyum in particular.

A modern conceptual approach to a study of the ecological and hydrogeological transformation of the qualitative composition of drinking groundwater of the buchak-kaniv aquifer in the central part of Dnipro-Donetsk artesian basin in the current natural-technogenic condi-tions has been proposed in the article. A rational unification of the indicators that characterize geological, ecological-hydrogeological and neotectonic conditions of the territory has been done. According to these conditions – natural and technogenic factors of the water quality deterioration of the target aquifer have been identified and investigated at the present stage. The spatio-temporal patterns of changes in the chemical composition of the studied waters during the period of active complex technogenic influence on the geological environment of the region (1960-2015) have been revealed. The main pollutant elements of these waters have been established, with their distribution at depth and surface by genesis. The elements-indicators of qualitative composition transformation of the groundwater have been determined. The authors have traced the dynamics exhibiting an increase in its content during long-term exploitation at about 20 powerful urban water intakes within the work area. According to this approach, measures for the stabilization of the waters’ chemical com-position at the buchak-kaniv water intakes of the research area have been developed. The authors justified a methodical approach to the prediction of groundwater ecological condition changes under the influence of the established ecological and hydrogeological factors. The measures of eco-friendly groundwater management at strategically important water intakes within the region have been proposed. Recommendations have been given for both existing and prospective water intakes.