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А new Vovchansk Uranium Ore district is allocated within the Orikhiv-Pavlohrad structural-metallogenic zone (SMZ) of the Azov metallogenic region. It is represented by Dibrova REE-U-Th deposit and a number of less studied ore occurrences. This deposit, according to ore mineralogy and age, geological and structural features, can be related to potassium-uranium metasomatite type. Dibrova deposit is considered to be possible analogue of mineralization of the Central Ukrainian Uranium Ore district. Among the main diagnostic characteristics of Dibrova deposit are: 1) location within the Mesoarchean trough-like structure superimposed on the Paleoarchean basement. 2) Spacial and genetic association with Paleoproterozoic two-feldspar granitoids of Dibrova type, which are considered to be related to Saltychia intrusive complex. 3) Regional and local faults, favorable for emplacement of numerous bodies of aplite-pegmatitic granitoids and associated intensive metasomatic alterations of rocks. The flexural fold was formed at the intersection of multidirectional faults, which is also favorable for ore mineralization. 4) Mineralization is confined to metasomatically altered aplite-pegmatites, less often to microcline quartzites of Dibrova suite. 5) K2O/Na2O ratio of ore-bearing granitoids reaches 3.5 and thorium-uranium ratio varies from 1.0 to 4.0. 6) Ores are composed by quartz (70–90 %) as predominant mineral and microcline. Minor minerals (up to 10–15 %) are represented by sillimanite, muscovite, biotite. 7) Accessory minerals include monazite, zircon, rutile, nasturan, brannerite, uraninite, molybdenite. 8) Among trace elements are niobium, lead, molybdenum, bismuth, copper, zinc and tin. Economic REE-U-Th mineralization was da­ted at 1.9–2.2 billion years. It is formed through circulation of hydrothermal-metasomatic fluids associated with the emplacement of Paleoproterozoic aplite-pegmatitic granites of the Dibrova type. Study of monazite and uraninite inclusions by the CHIME techniques confirms the Paleoproterozoic age of mineralization, 2085–2115 Ma. At the same time, the influence of Mesoarchean Yanvarske granitoids for the formation of REE mineralization during early pre-ore stage is not excluded.

The most important molybdenum mineralization of the Middle Dnipro province is limited to the Mesoarchean (3,1–2,9 Ga) Greenstone belts or structure (GSS). These are next occurrences: East-Sergiivka, Solone in the Sura GSS and Gannivka (district “Chervona”) in the Kryvyi Rih GSS. They have spatial combining or closeness with well-known gold deposits and occurrences: East-Sergiivka and Solone occurrences are located on the Eastern flanks of the Sergiivka and Balka Zolota deposits, respectively, in the sublatitudinal ore-bearing zones. From the West to the East gold mineralization gradually changes to gold-molybdenum and molybdenum. Gannivka molybdenum and Zhovtіanka gold occurrences are adjacent and localized in the submeridional zone of the Kryvyi Rih-Kremenchuk fault, and not spatially combined. However, similar to the etalon Lobash deposit, they can be combined as elements of a common ore-generating system related to a submeridional-extended granite massif undiscovered by erosion. In the process of previously performed geological surveys and related research, these ore prospects were studied and evaluated separately for each type of minerals. It is proposed to carry out further geological research in the context of spatially and genetically combining of gold and molybdenum mineralization. First of all it concerns deposits and occurrences of Sura GSS, where it is rationally to place two complex gold-molybdenum deposits: Sergiivka and Balka Zolota. This approach, which involves carrying out mining and exploration works on a joint scientific and technical base for molybdenum and gold ores, will undoubtedly have good economic efficiency and, ultimately, substantially increase the investment attractiveness of one or another deposit, facilitate the early launch industrial exploitation.

Based on our new U–Pb isotope data (SHRIMP-II) for the Voronezh Crystalline Massif (VCM) and on published U–Pb data for the Archean rocks of the Ukrainian Shield (USh), we have substantiated the main stages of the Archean evolution of the Sarmatian crust, a fragment of the basement of the East European Platform. New data have been obtained for 20 indicative rocks of the Kursk block (KB) of the VCM. We compared the Eoarchean and Paleoarchean KB rocks (mafic rocks and tonalites of the Oboyan’ complex), orthogneisses of the USh Dniester–Bug province (Bug granulite complex), and tonalites and mafic rocks of the USh Azov Province and have established the existence of ancient continental crust (3.75–3.60 Ga) in Sarmatia. The presence of Paleoarchean xenogenic zircons in younger intrusions indicates a wide spread of Paleoarchean rocks in the deep VCM crust section. In the Mesoarchean (3.2–3.0 Ga), eastern Sarmatia (KB and Azov and Middle Dnieper provinces) was a single granite–greenstone terrain. Two stages of felsic magmatic activity have been dated: 3.15–3.10 Ga (volcanics in the greenstone belts and tonalite–trondhjemite granites in the VCM and USh) and 3.05–3.00 Ga (volcanics and tonalite–trondhjemite granites in the USh and granites in the VCM KB). Magmatic and tectono-metamorphic processes (2.95–2.85 Ga) have been established throughout the eastern part of Sarmatia. The latest Mesoarchean endogenic activity (2.85–2.80 Ga) testifies to the tectonic differentiation of the area. Mafic and felsic magmatism, deformations, metamorphism, and ultrametamorphism under amphibolite and granulite facies conditions took place in the most part of the KB and in the Azov and Bug areas. It is shown that ultrametamorphic granites formed from an ancient (3.0–3.5 Ga) protolith. The USh Middle Dnieper province had a different tectonic position. Here, intrusion of post-tectonic granites and formation of mature sediments proceeded at 2.81–2.86 Ga. Our geochronological data show that most of the Sarmatian continental crust formed in the Mesoarchean as a result of both the intrusion of juvenile material and the reworking of the older protolith rocks. Neoarchean events (2.8–2.5 Ga) are weakly expressed in Sarmatia in contrast to Baltia, another large fragment of the East European Platform basement, where endogenic processes at 2.65–2.75 Ga were the major crust-forming geologic events.

This report presents data on the geological structure and location of the orthopyroxenite inclusion in gneissic enderbites of the Bug granulite–gneiss domain. Three stages of orthopyroxenite formation were identified on the basis of studies of the mineral composition along with the U–Pb and Lu–Hf isotope systems of zircons.