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The results of geological and lithological–geochemical investigations of the Devonian, Permian, Jurassic and Miocene evaporite deposits of Ukraine are presented in review. The main regions of evaporite distribution are the Dnipro–Donets depression, Carpathian (Forecarpathians, Transcarpathians) and Foredobrogean regions. The data on tectonics and stratigraphy are presented and information on lithology, the mineralogical and geochemical study of gypsum, anhydrite, rock and potash salts are summarized. The rich mineral composition of the Miocene evaporites in the Carpathian Foredeep (more than 20 salt minerals) is demonstrated, and the unique superimposed hydrothermal mineralization in the rock salt of salt domes from the Dnipro–Donets depression is presented (containing about 40 high- and mid-temperature hydrothermal minerals). In particular, the results of brine inclusion studies in evaporite minerals suggest that seawater was the main source of most of the salts. The brines in both the Miocene and Permian evaporite basins are classified as the Na–K–Mg–Cl–SO4 (SO4-rich) chemical type and the Jurassic and Devonian belong to the Na–K–Mg–Ca–Cl (Ca-rich) type. Temperature of solutions during halite precipitation shifted from 25 to 43 °C, while during the stage of potash salt sedimentation it apparently increased to 40–83 °C.

Fundamental and applied achievements in the fields of geochemistry and thermobarometry of mineral-forming fluids and thermobarogeochemistry of evaporites are summarized as the basis of the corresponding world-famous scientific thermobarogeochemical schools established by professors V. A. Kalyuzhny and O. Yo. Petrychenko at the Institute of Geology and Geochemistry of Combustible Minerals of the Academy of Sciences of Ukraine on the basis of creative development of ideas of predecessors with the support of academicians Ye. K. Lazarenko, V. S. Sobolyev, H. N. Dolenko. Emphasis is placed on the contribution of schools to geological science, which is determined by the formed knowledge base on geochemical and thermobaric parameters of fluid environments of mineral-ore- naphthidogenesis in the Earth’s lithosphere (according to data of fluid inclusions research). In this context, in view of the enormous array of available data, the composition, physicochemical properties, genesis of fluids of the upper mantle and crust are briefly discussed and it is shown that the course of processes of petro-, mineral-, ore-, naphthidogenesis and formation fields of hydrocarbon, ore and non-ore minerals is determined by the peculiarities of degassing (defluidization) of the Earth and its influence on the conversion of carbon compounds during terrigenous, organogenic, hemogenic sedimentation and on the processes of diagenesis of sediments of various origins. The obtained data on the reproduction of the evolution of the fluid regime of rock complexes contribute to solving the fundamental problem of geochemistry of carbon and hydrogen (hydrocarbon-hydrogen matter) and deep (endogenous) fluid flows in the Earth’s lithosphere as an important basis for mineralofluidological model of the planet. They played a decisive role in substantiating at the Institute on the basis of abiogenic-biogenic dualism universal approaches to the processes of synthesis and genesis of natural hydrocarbons in the form of a new fundamental paradigm of oil and gas geology and geochemistry, the polygenesis of natural hydrocarbons in the Earth’s bowels, which increases the potential of oil and gas resources of promising regions, including Ukraine. This creates the preconditions for the identification of promising rock complexes for hydrocarbon, ore and non-ore minerals by applying the obtained fundamental thermobarogeochemical data in forecasting, exploration and operational practice on the basis of developing of new non-traditional geotechnologies for assessment and exploration of hydrocarbons and minerals.

<p>Middle Miocene crystals of sabre gypsum and subcrystal of giant gypsum intergrowth cropping out in southern Poland near Busko have been analysed for their Sr isotope composition. The new isotopic data revealed fluctuations in <sup>87</sup>Sr/<sup>86</sup>Sr values within the primary gypsum crystals providing new insight into paleohydrological conditions during the Badenian salinity crisis in the Polish part of the Carpathian Foredeep Basin. The isotopic composition of a glassy gypsum subcrystal decreased progressively with the subcrystal growth, ranging from 0.70892 to 0.70884 near the crystal apex. The <sup>87</sup>Sr/<sup>86</sup>Sr ratios of the sabre gypsum crystals are in the range of 0.70887–0.70934 and there are significant fluctuations within each gypsum layer tested. Similar intra-layer fluctuation patterns observed in various sections provide a strong argument for the synchronous origin of the investigated portions of the sulphate successions.  </p><p>The studied primary gypsum has a more radiogenic composition than the Badenian seawater. Its isotope signatures reflect spatial and temporal changes in the supply of continental derived radiogenic Sr to the Carpathian Foredeep Basin. Contrary to previous studies, the Palaeozoic clastic rocks of the Holy Cross Mountains are suggested as potential sources of radiogenic strontium. The new Sr isotope data support a salina model for the evaporitic basin of the Carpathian Foredeep.</p><p>This study was supported by the Polish National Science Centre, grant No. 2017/27/B/ST10/00493.</p>

On the basis of morphological analysis and detailed studies of lithological-facies composition and formation conditions of coal-bearing deposits the investigations of the lower part of Carboniferous deposits of the Lviv-Volyn Basin of south-western edge of the East European Platform were conducted. In particular, the available geological material was analyzed; the initial conditions of Carbonic coal-forming (Late Tournai – beginning of Late Visean) were studied and positions of the lower boundary of the coal-bearing formation were grounded; the availability of commercial coal-bearing potential (thickness of coal seams 0.6 m and more) of the lower part of Carbonic was studied; commercial coal-bearing potential of the Visean and the lower part of the Serpukhovian stages of the lower subformation of the basin was detected; the influence of intraformational and epigenetic washings and other factors that caused the formation and changes of the lower part of the coal-bearing formation, the morphology were investigated; the possibilities of commercial development of coal seams of the lower horizons were grounded. The most promising areas for searching commercial coal seams and the plots with workable thickness in deposits of the lower coal-bearing subformation were singled out for the extension of commercial coal-bearing potential and determination of the directions of searching and prospecting for promising coal deposits of the basin. It was noted that within the bounds of such areas (the Kovel area, the Bubnivska area, the Busk field and other) a continental regime was formed for a long time, and in the conditions of the marshy near-sea lowgrounds with a developed river system and dismembered paleorelief the periodical peat accumulation occurred that caused the formation of commercial coal seams. Reliable prediction of the mining-geological conditions for the development and the assessment of the commercial usability of the coal seams of the lower part of Carbonic deposits in the whole territory of the basin and within the limits of acting mines should ensure the stable development of the Lviv-Volyn Coal Basin.