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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 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.