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The materials of several articles and reports published in 2022 by the authors of this work and V.P.Kirilyuk (Kirilyuk, 2022 a,b), who discussed the structure and stratigraphy of the Вug area granulite complex of the Ukrainian Shield. The authors, relying on their geological, geophysical and geochemical studies, isotopic geochronology data, as well as on the world experience in studying the Early Precambrian complexes of the Canadian and Australian shields, argue that during 3.8—1.7Ga, the Bug area granulite complex underwent at least a threefold structural metamorphic processing. Its modern structural plan, as well as, to a large extent, the composition and structural and textural features of metamorphic rocks, are of Early Proterozoic age. Therefore, its division into suites of primary sedimentary-volcanogenic rocks and their vertical distribution by age does not make sense. Only a division into two series is possible — the Dniester-Bug and the Bug, between which there is a tectonic contact. Contrary to this, V.P.Kirilyuk, relying on the experience of his stratigenic-metamorphogenic studies and the authority of the well-known school of L.I.Salopa, E.M.Lazko et al., defends the point of view on the stratigenic nature of the Bug area granulite complex, in which the primacy and stability of the position of strata-formations relative to each other were preserved throughout the entire time. According to V.P.Kirilyuk, there are no breaks and disagreements between the suites, so he proposes to abandon the identification of the early Precambrian USh Bug Group. And the seven suites identified by him, the youngest of which is 3.8 billion years old, are proposed to be attributed to a single Dniester-Bug series. The authors of both alternative points of view apply to the National Stratigraphic Committee of Ukraine with a proposal to revise the stratigraphic scheme of the Early Precambrian of the USh., Розглянуто матеріали декількох статей і доповідей, опублікованих у 2022 р. авторами цієї публікації і В.П. Кирилюком, у яких розгорнулася дискусія відносно структури і стратиграфії Побузького гранулітового комплексу Українського щита. Автори, спираючись на свої геолого-геофізичні та геохімічні дослідження, дані ізотопної геохронології, а також на світовий досвід вивчення ранньодокембрійських комплексів Канадського і Австралійського щитів, стверджують, що протягом 3,8—1,7 млрд років побузький гранулітовий комплекс зазнав як мінімум триразової структурно-метаморфічної переробки. Його сучасний структурний план і значною мірою склад та структурно-текстурні особливості метаморфічних порід мають ранньопротерозойський вік. Тому поділ цього комплексу на світи первинних осадово-вулканогенних порід і розподіл їх за віком у розрізі не мають сенсу. Можливим є лише поділ на дві серії — дністровсько-бузьку та бузьку, між якими існує тектонічний контакт. Всупереч цьому, В.П. Кирилюк, спираючись на досвід своїх стратигенно-метаморфогенних досліджень і авторитет відомої школи Л.І. Салопа, Є.М. Лазька та ін., відстоює позицію щодо стратигенної природи побузького гранулітового комплексу, в якому первинність і стабільність положення товщ-світ одна відносно одної зберігалися протягом усього часу. На думку В.П. Кирилюка, перерв і незгідностей між світами не існує, тому він пропонує відмовитись від виділення в ранньому докембрії Українського щита бузької серії. Виділені дослідником сім світ, вік наймолодшої з яких дорівнює 3,8 млрд років, він пропонує віднести до єдиної дністровсько-бузької серії. Автори обох альтернативних поглядів звертаються до Національного стратиграфічного комітету України з пропозицією перегляду стратиграфічної схеми раннього докембрію УЩ.

The wide-angle reflection and refraction (WARR) SHIELD’21 profile carried out in 2021 crosses from SW to NE the main tectonic of Ukraine. The SHIELD’21 targeted the structure of the Earth’s crust and upper mantle of the southwestern margin of the East European Craton with overlying Neogene Carpathian Foredeep and Vendian-Paleozoic Volyn-Podolian Monocline, Archaean and Paleoproterozoic segments of Ukrainian Shield and Late Paleozoic Dnieper-Donets Basin. The ~650km long profile is an extension of realized in 2014 RomUkrSeis line in Romania and Ukraine from Apuseni Mountains to southwestern Ukrainian Shield. The field work performed in 2021, included the deployment of autonomous seismic stations and drilling-explosive works. A total of 264 seismic receivers were deployed (160 DATA-CUBE and 104 TEXAN stations) with the average spacing between the observation points about 2.65km. The sampling interval for all stations was 0.01s. Seismic energy was generated by 10 shot points with ~50 km of distance between them and total charge in all wells 5775 kg. The SHIELD’21 experiment using TEXAN and DATA-CUBE short-period seismic stations provided high-quality seismic records. The main recorded seismic waves are the refractions of P- and S-waves in sediments, basement, crust and upper-most mantle, and reflections from crustal boundaries, Moho interface and boundaries in the uppermost mantle. Correlation of travel time arrivals of seismic waves provides calculation of the velocity model for both P- and S-waves. The main objective of the SHIELD’21 project is to get new seismic data that increase our knowledge on the lithosphere structure as well as geodynamics of the oil-and-gas-bearing and ore regions of Ukraine., Сейсмічний профіль ГСЗ (англійський варіант — WARR) SHIELD’21, відпрацьований у 2021 р., перетинає з південного заходу на північний схід основні тектонічні структури України. Профіль спрямований на вивчення структури земної кори та верхньої мантії південно-західної окраїни Східноєвропейського кратону, яку перекривають венд-палеозойська Волино-Подільська монокліналь і неогеновий Передкарпатський прогин; архейського і палеопротерозойського сегментів Українського щита; пізньопалеозойської Дніпровсько-Донецької западини. Профіль SHIELD’21 (загальна довжина ~650 км) є продовженням раніше реалізованого у 2014 р. на територіях Румунії та України профілю RomUkrSeis від гір Апусени до південно-західної частини Українського щита. Дослідження WARR уздовж профілю SHIELD’21 з використанням короткоперіодичних сейсмічних станцій TEXAN і DATA-CUBE забезпечило реєстрацію сейсмічних коливань високої якості. Польові роботи, які були виконані у 2021 р., включали розгортання автономних сейсмічних станцій та про[1]ведення бурових і вибухових робіт. Усього було задіяно 264 сейсмічних приймача (160 станцій DATA-CUBE і 104 станції TEXAN), середня відстань між якими становила 2,65 км, а дискретність запису для всіх станцій складала 0,01 с. Сейсмічна енергія генерувалась у 10 пунктах вибуху з середньою відстанню між ними близько 50 км та із сумарним зарядом у всіх свердловинах 5775 кг. Основними зареєстрованими сейсмічними хвилями є заломлені P- і S-хвилі, а також відбиття від границь в осадових відкладах, фундаменті, земній корі, розділі Мохо та границь у верхній мантії. Підбір зафіксованих годографів за часом дає змогу побудувати швидкісну модель за P-, та S-хвилями. Основна мета проекту SHIELD’21 є отримання нових сейсмічних даних, які поглиблять наші знання про структуру та геодинаміку літосфери нафтогазоносних і рудних регіонів України.

The aim of the study, the results of which are presented in this article, is to study changes in the composition of hydrothermal fluid ore systems of the early Precambrian on the example of gold and uranium ore deposits of the Ukrainian shield in connection with the evolution of exo- and endogenous processes in the outer shells of the Earth. The method used is a complex isotope-geochemical study of the composition of gas-liquid inclusions of hydrothermal fluid of ore systems. Based on experimental isotope-geochemical studies of the fluid of gas-liquid inclusions in the minerals of Precambrian deposits of uranium and gold of the Serednoprydniprovsky and Ingul megablocks of the Ukrainian Shield, a consistent change in the quantitative and isotopic composition of hydrothermal fluids of mineral formation from Mesoarchean to Paleoproterozoic was established. The content of H2O and CO2 was investigated and the isotopic composition of carbon CO2 fluids in quartz, pyrite, and feldspar were studied. The age range of the studied deposits is 3200—1750 million years. A decrease in the carbon dioxide content in the hydrothermal mineral-forming fluid of the Precambrian occurred in the Neoarchean, that is, before the Great Oxygen Event (Great Oxidation Event) — an increase in the oxygen content in the atmosphere in the Paleoproterozoic and is probably associated with the processes of exogenous and endogenous hydration of ultramafic rocks during the formation of the protocontinental crust. Molar fraction of CO2 in the mineral-forming fluid, in the Precambrian correlates to some extent with atmospheric pressure. The increase in the content of the carbon-12 isotope in the Paleoproterozoic in the mineral-forming fluid occurred due to the oxidation of organic matter with an increase in the oxygen content in the atmosphere., Мета дослідження, результати якого викладені в даній статті, — вивчення змін у складі гідротермальних флюїдних рудних систем раннього докембрію на прикладі золоторудних та урановорудних родовищ Українського щита у зв’язку з еволюцією екзо- і ендогенних процесів у зовнішніх оболонках Землі. Застосована методика — комплексне ізотопно-геохімічне дослідження складу газово-рідких включень гідротермального флюїду рудних систем. На підставі експериментальних ізотопно-геохімічних досліджень флюїду газово-рідких включень у мінералах докембрійських родовищ урану і золота Середньопридніпровського і Інгульського мегаблоків Українського щита встановлена послідовна зміна кількісного та ізотопного складу гідротермальних флюїдів мінералоутворення від мезоархею до палеопротерозою. Досліджено вміст Н2О і СО2 та ізотопний склад вуглецю СО2 флюїду в кварці, піриті і польовому шпаті. Віковий діапазон досліджуваних родовищ — 3200—1750 мільйонів років. Зменшення вмісту вуглекислого газу в гідротермальному мінералоутворювальному флюїді докембрію відбулося в неоархеї, тобто раніше Великої кисневої події (Great Oxidation Event), — збільшення в палеопротерозої вмісту кисню в атмосфері, ймовірно, пов’язане з процесами екзогенної та ендогенної гідратації ультраосновних порід при формуванні протоконтинентальної кори. Молярна частка СО2 в мінералоутворювальному флюїді докембрію певною мірою корелює з атмосферним тиском. Вміст ізотопу вуглецю-12 у палеопротерозої в мінералоутворювальному збільшився в результаті окиснення органічної речовини при збільшенні вмісту кисню в атмосфері

Based on modern lithochemical dataset statistical processing methods, the chemical composition features of the Paleoproterozoic iron ore (iron-siliceous) formation of the Saksagan Formation of the Kryvyi Rig basin of the Ukrainian Shield have been clarified with a view to improve the lithochemical systematics of the Precambrian iron-siliceous formations and to elucidate the general paleogeo-graphic (climatic, facies) conditions of their clastogenic-chemogenic sedimentation. A series of binary diagrams illustrates the relation-ship between iron-siliceous and shale layers. Using the cluster analysis method, lithochemical typification of shale rocks of the iron-siliceous formation was carried out: 12 "elementary" clusters were distinguished between two lithochemical groups and four subgroups separated by the mineral composition. The correspondence between lithochemical and mineral types of shale rocks has been indicated. The lithochemical types are arranged in a regular sequence, which corresponds to the initial authigenic-mineralogical and authigenic-lithofacial zonality of the sediments and allows, in general, denoting the facies isomorphic series of meta-sediments from metaclasto-genic to metachemogenic ones. An empirical classification diagram of rocks in the coordinates Al2O3 and (Fe2O3 + FeO) is proposed for dividing them into areas of chemogenic, chemogenic-clastogenic, and clastogenic sedimentation. The most iron-rich rocks – sec-ondarily unoxidized red-banded jaspilites – are characterized by the highest Fe2O3 / FeO ratio, which indicates their formation under shallow, well aerated conditions. The lithochemical features of the rocks in combination with the peculiarities of their occurrence, stratification and distribution confirm, on the whole, the protohumid type of lithogenesis in the conditions of low-lying shallow basins with a subplatform tectonic regime.

The second article discusses the 5 main types of stratogenic metamorphic complexes found in the East-European and Siberian platforms: 1) granulite-gneissic; 2) amphibolite-gneissic; 3) greenstone; 4) ferruginous-siliceous-schistose (metavolcano-chemo-terrigenic) 5) gneiss-schistose (metacarbonaceous-terrigenic). The types of complexes, in addition to the fact that they differ in the degree and type of metamorphism, also have different geologic-formational composition. These complexes are seen as the largest regional stratigraphic subdivisions in all regions of the Early Precambrian. They are represented with varying degrees of completeness on the Aldan-Stanovian, Anabarian and Baltic shields and on the Voronezh crystalline massif. The most complete stratigenic metamorphic complexes are developed on the Ukrainian and Aldan-Stanovian Shields. The complexes of the various regeions are mutually correllated between themselves and the Ukrainian Shield based on them corresponding to the types of stratogenic metamorphic complexes. The similarities between the complexes across different regions are to most researchers evidence not only of similar conditions of the formation of same-type complexes, but also, most likely, their conformance to identical quasi-synchronous stages in the development of the Earth’s core. Based on the results of both articles of the cycle, it is concluded that the largest divisions of the current Chronostratigraphic Scheme of the Early Precambrian of the Ukrainian Shield, which are shown in it as “series”, deserve either the transfer to the rank of “stratigraphic complexes” or the inclusion in the complexes by uniting series. Combining of the series concern to granulite-gneiss complexes that need to be renamed in the updated stratigraphic scheme. For other complexes, for the sake of inheritance with the previous schemes, it is advisable to preserve the geographical names of the series.

The article presents the results of the study of the mineral composition of ore albitites and the chemical composition of feldspars of the Par-tyzan thorium-uranium deposit of the Partyzan ore field of the Central Ukrainian uranium ore area of the Kirovograd metallogenic region of the metallogenic province of Ukrainian Shield. According to the results of electron microscopic examination of the thin sections from the zone of near-ore changes of the original granite, it is established that albite is the main mineral of the zone of near-ore changes of the Partyzan deposit. A preview of the transparent thin sections on a polarization microscope revealed the presence of feldspars in the rock which are similar to potassium feldspar (orthoclase and microcline) of the original granite in terms of the internal structure. However, in the process of electron microscopic studies, it was found that the major mineral of the investigated sections is albite. In a considerable number of cases, these are albite pseudomorphoses on the original crystals of orthoclase, microcline, and oligoclase with preservation of the internal structure and morphology of the starting minerals. The composition of dark-colored minerals is classified as actinolite-diopside and chlorite-epidote varieties of these metasomatites. Among the accessory and ore minerals were found the following: magmatic (relict) – zircon, apatite, monazite; pneumatolitho-hydrothermal – siderite, barite, titanite, torite, hematite, nasturan, galena; unrecognized – coffi-nite (?), uranium-thorium-rare earth minerals (mixture). Near-ore pneumatolitho-hydrothermal rocks of the deposit are classified as apogranitic albitites, the posterior zone of the column of alkaline sodium metasomatites of the fault zones. This confirms the results of a field survey carried out by the Search and survey expedition № 46 of KP "Kirovgeologiya" and aimed at an intersection of Partyzan deposit albitites, as well as the validity of the classification of the near-ore changes as a geological formation of alkaline sodium metasomatites of deep fault zones.

The article presents the results of study of the isotopic composition of oxygen and carbon of carbonates in ore deposits of the Early Pre-cambrian of the Ukrainian Shield. The following objects were studied: 1. Iron ore formations of the Kryvyi Rih ultra-deep well, where car-bonates were extracted from all units of the Kryvyi Rih Paleoproterozoic series, as well as from the Archean rocks of the Dnipropetrovsk complex. 2. Uranium ores and host rocks of the Severynivsky deposit of the uranium-albite formation of the Paleoproterozoic age. 3. Gold deposits of Archean greenstone structures of the Dnieper, including: Sergiivske (Au-pyrite and Au-Bi-Te ores) and Balka Shyroka (Au-glandular and Au-Ag-Pb-Zn ores). Genetically, the carbonates of the compared areas show signs of primary sedimentary carbonate for-mations that have experienced the influence of hydrothermal-metasomatic processes. The temperature conditions of their formation indicate a change in the mode of carbonate formation from progressive in the temperature range of 70-150°C (diaphthoresis) - 220-300°C (meta-somatosis) to regressive: up to 180-80°C (late veins). Compared to Archean carbonates, Proterozoic carbonates are inherently heavier oxygen and light carbon. The scarnoid mechanism of the formation of the ore halo in a highly magnesian environment explains the se-quence and metasomatic nature of carbonation. The environment and conditions of mineral formation are favourable for the growth of large metacrystals of dolomite, calcite, actinolite and tremolite; as confirmed by the study of fluid inclusions. The presence of ore minerals in inclusions in calcite confirms the ore-forming nature of the studied fluid. Among the granitoids of the Dnipropetrovsk complex, sites similar to the graphite-carbonate rocks of the Gdantsev Formation are noted, including the isotopic composition, which are characterized by intense tectonic disturbances. In such zones of decompression, a significant drop in temperature is observed. All this suggests that there is a system of large faults (tectonic wedges) in this region of Kryvbass, with the immersion of fragments composed of rocks of the Kryvyi Rih series into more ancient granitoids.

In the central part of the Ukrainian Shield are allocated two independent structural elements: Inhul block and Inhulets-Kryvyi Rih suture zone, instead of the Inhul-Inhulets region, according to the current tectonic zoning in “Correlation Chronostratigraphic Scheme of the Early Precambrian of the Ukrainian Shield”. The stratigraphic dividing of this territory has not undergone any changes. The article suggests existing Inhul-Inhulets Series in this scheme to divided into two: the Inhul (Inhul block) and the Inhulets (Inhulets-Kryvyi Rih suture zone) and several independent strattons in the Suites rank. As part of the Inhul Series, the upper part of the Inhul-Inhulets Series remains as part of the Kamianokostuvatska and Roshсhakhivska (Bratskа SFZ) and Spasivska and Checheliivska (Inhul SFZ) Suites. In the lower part of the section, there is an independent Rodionivska Suite. The West Inhulets and Kryvyi Rih-Kremenchuk SFZ stratigraphic sections of the Inhulets-Kryvyi Rih suture zone are identical and completely correlate with each other: lower Mesoarchean metaterigenic Lativska Suite is basal for both, Mesoarchean metavolcanogenic Nyzhnozelenorichanska Suite of the West-Inhulets SFZ is correlated with the Novokryvorizka Suite of the Kryvyi Rih-Kremenchuk SFZ, Paleoproterozoic Inhulez Series – respectively, with the Kryvyi Rih Series (metavolcanogenic-sedimentary Verkhnozelenorichanska Suite – with the Skeliuvatska Suite, and the metaterigenic-ferrous Artemivska Suite – with the Saksaganska), carbonate-carbon-terigenic Rodionivska Suite – with Hdantsivska. These stratigraphic units represent by themselves their own suture formations of the Inhulets-Kryvyi Rih suture zone.

On the basis of study of Umansk, Novograd-Voolynsk and Novoukrainsk granitoid massif of western and central parts of the Ukrainian shield by tectonophysical methods intensely deformed state of the earth's crust in the period between 2,02—2,05 Ga has been revealed. The single paleofield of tectonic stress for Nemirovsk and Lelekovsk stages has been restored. A refined scale of deformation stages of the north-western and central part of the Ukrainian Shield in the time interval 2,45—1,73 Ga has been composed. The idea of counter-clockwise turning the western part of the shield relative to its central part during the interval of 2,02—2,05 Ga is being substantiated.

Results of modern experimental electromagnetic studies completed during 2005-2014 along 13 profiles located mainly within suture zones of the USh have been given. The main result of geo-electric studies of the USh is the revealing of numerous local and regional anomalies of electric conductivity according to the data of 3D modeling, the presence of low-resistance deep anomalies, confined to zones of metasomatism along extensive fault zones; conjugation of low-resistance anomalies with metallogenic ore knots and geochemical anomalies.

Zircon occurs as a minor constituent in most differentiated magmatic rocks. Its robustness to later modification means that its isotopic and chemical composition generally records conditions prevailing when it formed, and the systematic changes in the oxygen isotope record of zircon through geological time have been used to trace the temporal evolution of crust–mantle interaction and intra-crustal recycling. Here we present U–Pb, Hf, and oxygen isotopic compositions for high grade metamorphic Archean rocks from the Dniester-Bug Series, western Ukrainian Shield. Zircon from a quartz-dominated rock is up to 3.8 Ga old, and enriched in 18 O compared to most previously reported values from Archean zircon. Similar values are recorded in zircon cores, which exhibit a variety of internal textures including magmatic-style oscillatory zonation, and rims. If this rock is metasedimentary and the isotope signatures in cores are primary, the zircon sources were characterized by heavier oxygen isotopic compositions than any known major area of Archean crust. Alternatively the O isotope compositions have been modified. We show that a large fraction of the analyzed zircon appear not to be modified by radiation damage, and speculate that O exchange may have taken place by diffusion during extreme metasomatic alteration of the host rock. The possibility that igneous-looking, apparently unaltered zircon may not preserve a primary oxygen isotope signature has implications for its use in the interpretation of crustal evolution, including early terrestrial geodynamics.

International audience; Palaeoproterozoic (ca. 1.8 Ga) mafic and ultramafic dykes are widely distributed within the whole Sarmatian segment of the East-European craton. This paper focuses on new geochronological, geochemical and isotope data obtained for mafic and ultramafic dykes of the Ingul terrain. Geochronological data available for these dykes indicate ages around 1800 Ma. We provide a new U–Pb zircon age of 1810 ± 15 Ma obtained for a dolerite dyke in the Kirovograd area. Geochemical and petrographical data allow identification of three groups of dykes: (1) kimberlites, (2) high-Mg# subalkaline rocks (picrite, camptonite, subalkaline dolerite etc.) and (3) tholeiite dolerite. Rocks of these groups were probably derived from different sources. εNd1800 values of studied rocks vary from 0.7 to 2.8. The highest values were obtained for mantle xenoliths and their kimberlite host (εNd1800 = 2.5–2.8). Rb–Sr data yield a regression age of 1729 ± 20 Ma with an initial 87Sr/86Sr = 0.70366 ± 41 (MSWD = 10.8). The whole-rock lead isotope data scatter, but data for sub-groups of samples can tentatively be fitted to parallel 1.8 Ga isochrons. The geochemical data indicate rocks to have formed by partial melting and the degree of melting is thought to be a function of formation depth, the latter ranging from sub-lithospheric to lower-crustal levels; we assume that melting was caused by a mantle plume. Dyking in the Ingul terrain was closely associated in time and space with metasomatic albitites that host numerous economic U deposits.

Stratigraphy of metamorphic Precambrian complexes related to Paleo-Proterozoic is controversial. An additional sign permitting to correlate strata may be their material composition because in the Precambrian composition of deep fluids changed regularly. Then some regularity in changes of composition of magmatic and metamorphic rocks has to exist. The rocks produced during this time are dolomite and calcite. Quartzite, carbonaceous shist and graphite gneiss are also abundant. Only during this activation of Precambrian carbonatite volcanic activity became apparent. The author’s method has been used generalizing the special features of magmatic and metamorphic rocks of the Ukrainian shield, which allowed reconstructing the course of the deep process and composition of melts and fluids in the layer of melting. Subdivision of the shield into blocks of two types has been proposed: inherent blocks and the areas spatially attached by suture zones. The blocks differ by decisive role of the fault zones formed before granitization; the presence of gabbro-montsonite-trachite granites massifs formed before granitization (2,1—1,99 Ga ago); mutual transitions between intusive and palingenous granites; formation of anorthosite-granite massifs after granitization. Activation consists of two tectono-magmatic cycles separated by granitization. Composition of rocks attached to suture zones is effected by oxidized deep melts and fluids. We can make estimation on geodynamic process and composition of deep fluids in blocks by composition of magmatic rocks. In blocks fault zones are generated with multiple intrusion of melts along them, differentiated under the crust. Neutral-alkalescent aquatic-chloride-potassium fluids take part in differentiation of melts. Composition of fluids changes after granitization under the whole shield. Immediately after it the massifs of carbonatites and alkaline rocks are formed where alkaline ultrabasites are also present. In the territories attached to suture zones carbonate ferruginous layers appear, which include xenocrysts. In blocks in places of intersection of sub-longitudinal and sub-latitudinal zones, in relict foci mixing of melts takes place diluted by aquatic-chloride-potassium fluids and added deep carbonate-fluoride-sodium ones. Massifs of anorthosites-rapakivi-granites with titanium are formed. They are accompanied by pegmatite fields, albite-uranium metasomatites when joint participation of carbonate-fluoride-sodium and aquatic fluids is required.

The article deals with current “Сorrelation chronostratigraphic scheme of еarly Precambrian formations of the Ukrainian Shield” should be divided into two parts: the “Correlation stratigraphic scheme of the Lower-Precambrian formations” and “The scheme by age dividing of non-stratified Lower-Precambrian formations”. They have to be separately approved by two relevant subsections of the Lower Precambrian section NSC of Ukraine. Also, the role of intrusive and ultrametamorphic formations in determining of the stratum position in the stratigraphic scheme should be taken into account.

This research gained financial support granted by the Royal Society, UK (2006/R4 IJP), and the Swedish Institute, Sweden. This paper is NORDSIM contribution number 484, and publication no. 62 of the Large Igneous Provinces – Supercontinent Reconstruction – Resource Exploration Project (CAMIRO Project 08E03, and NSERC CRDPJ 419503-11) (www.supercontinent.org, www.camiro.org/exploration/ongoing-projects), and a contribution to IGCP 648. The Ukrainian shield hosts two Palaeoproterozoic anorthosite-mangerite-charnockite-granite (AMCG) complexes (the Korosten and Korsun-Novomyrhorod complexes) that intruded Palaeoproterozoic continental crust in north-western and central parts of the shield, respectively. We report results of U-Pb zircon and baddeleyite dating of 16 samples from the Korosten plutonic complex (KPC), and 6 samples from the Korsun-Novomyrhorod plutonic complex (KNPC). Fifteen zircon samples from both complexes were also analysed for Hf isotopes. These new, together with previously published data indicate that the formation of the KPC started at c. 1815 Ma and continued until 1743 Ma with two main phases of magma emplacement at 1800-1780 and 1770-1758 Ma. Each of the main phases of magmatic activity included both basic and silicic members. The emplacement history of the KNPC is different from that of the KPC. The vast majority of the KNPC basic and silicic rocks were emplaced between c. 1757 and 1750 Ma; the youngest stages of the complex are represented by monzonites and syenites that were formed between 1748 and 1744 Ma. Both Ukrainian AMCG complexes are closely associated in space and time with mantle-derived mafic and ultramafic dykes. The Hf isotope ratios in the zircons indicate a predominantly crustal source for the initial melts with some input of juvenile Hf from mantle-derived tholeiite melts. The preferred model for the formation of the Ukrainian AMCG complexes involves the emplacement of large volumes of hot mantle-derived tholeiitic magma into the lower crust. This resulted in partial melting of mafic lower-crustal material, mixing of lower crustal and tholeiitic melts, and formation of ferromonzodioritic magmas. Further fractional crystallization of the ferromonzodioritic melts produced the spectrum of basic rocks in the AMCG complexes. Emplacement of the ferromonzodioritic and tholeiitic melts into the middle crust and their partial crystallization caused abundant melting of the ambient crust and formation of the large volumes of granitic rocks present in the complexes. Postprint

As a result of petrochemical and geochemical studies of granitoid formations of the Ukrainian Shield and Western Transbaikalia by methods of mathematical statistics revealed that in the Ukrainian shield analogue of ore-bearing granite Hudzhyr complex can be granites of Kamennye Mogily complex. Specified as positional placement of a number of granitoid complexes of the Western Transbaikalia in the scheme of acid groups in the region., По результатам петрохимических и геохимических исследований гранитоидных образований Украинского щита (УЩ) и Западного Забайкалья методами математической статистики установлено, что на территории УЩ аналогом рудных гранитов гуджирского комплекса могут быть каменномогильские граниты. Предложены возможные варианты позиционного размещения некоторых исследованных гранитоидных комплексов Западного Забайкалья в схеме кислих образований региона., За результатами петрохімічних і геохімічних досліджень гранітоїдних утворень Українського щита (УЩ) і Західного Забайкалля методами математичної статистики встановлено, що на території УЩ аналогом рудних гранітів гуджірського комплексу можуть бути кам’яномогильські граніти. Запропоновано можливі варіанти позиційного розміщення деяких досліджених гранітоїдних комплексів Західного Забайкалля в схемі кислих утворень регіону.

The geochemical specialization and ore bearing ability of main types (alkaline magmatic and metasomatic rocks, differentiated granites and their pegmatites, Sc-U albitites) of crystalline rocks from the Ukrainian Shield are considered. The prospects, forecasting areas and exploration of rare metals (Zr, Nb, REE, Y) deposits are shown. As a main result of investigation, the evidence availability for exploration of rare metal deposits (non-traditional type) related to hypersolvus syenites is cited. The genetic relation of the ore-bearing syenites with rich Zr, Nb, Y ores (Azov, Yastrubetske deposits) to anorthosite-rapakivi granite plutons as well to South-Kalchyk massif have been exposed. That significantly expands area (up to 20 thousand km2) for exploration of such type deposits. The interpretation of alkaline metasomatites from East Azov area as fenites of carbonatite complexes allows considering this region as of great potential on carbonatitc type deposits. A new type of alkaline metasomatites enriched in rare-earth elements was found., Рассмотрены геохимическая специализация и рудоносность главных типов кристаллических пород Украинского щита: щелочные магматические и метасоматические породы, дифференцированные граниты и их пегматиты, Sc-U альбититы. Показаны перспективы и площади прогнозирования и поисков месторождений редких металлов (Zr, Nb, ТR, Y). Главным результатом исследования является доказательство перспективности гиперсольвусних сиенитов на поиски месторождений редких металлов нетрадиционного типа. Приведенные данные о генетической связи рудоносных сиенитов, к которым приурочены богатые Zr, Nb, Y руды (Азовское, Ястребецкое месторождения), с анортозит-рапакивигранитными плутонами и Южно-Кальчикским массивом. Это значительно расширяет площадь (более 20 тыс. км2) поиска месторождений такого типа. Интерпретация щелочных метасоматитов Восточного Приазовья, как фенитов карбонатитового комплекса, позволяет считать этот район перспективным на месторождения карбонатитового типа. Обнаружен новый тип щелочных метасоматитов, обогащенных редкоземельными элементами., Розглянуто геохімічну спеціалізацію і рудоносність головних типів кристалічних порід Українського щита: лужні магматичні і метасоматичні породи, диференційовані граніти і їх пегматити, Sc-U альбітити. Показано перспективи та площі прогнозування і пошуків родовищ рідкісних металів (Zr, Nb, ТR, Y). Головним результатом дослідження є доказ перспективності гіперсольвусних сієнітів на пошуки родовищ рідкісних металів нетрадиційного типу. Наведено дані про генетичний зв'язкок рудоносних сієнітів, до яких приурочені багаті Zr, Nb, Y руди (Азовське, Ястребецьке родовища), з анортозит-рапаківігранітними плутонами і Південно-Кальчицьким масивом. Це значно розширює площу (більше 20 тис. км2) пошуку родовищ такого типу. Інтерпретація лужних метасоматитів Східного Приазов'я, як фенітів карбонатитового комплексу, дозволяє вважати цей район перспективним на родовища карбонатитового типу. Виявлено новий тип лужних метасоматитів, збагачених рідкоземельними елементами.

On the basis of new factual material justified the selection of new formations within the two structural-facies zones of the south-western slope of the Ukrainian shield., На основе нового фактического материала обосновано выделение новых свит в пределах двух структурно-фациальных зон юго-западного склона Украинского щита., На основі нового фактичного матеріалу обгрунтовано виділення нових світ в межах двох структурно-фаціальних зон південно-західного схилу Українського щита.

Two rare metal leucocratic granites, Perga and Kamennaya complexes, can be distinquished on the Ukrainian shield. The Perga complex consists of medium- and coarse-grained, mainly porphyric, biotite, riebeckite and aegirine granites, granite porphyries, microclinites and albitites with rare metal mineralization (genthelvite, phenacite, tantalite, cassiterite and wolframite etc.). Granites from several stocks (up to 30 km2) in the northwestern part of the shield, situated along the fracture zone, restricted the large Korosten pluton of rapakivi granites to the northwest. The age of these granites (Pb-Pb and U-Pb methods on zircon and monazite) practically coincide with the age of rapakivi granites being 1750 Ma. Within the Korosten complex of rapakivi granites we consider that zinnwaldite granites, which are characterized by fluorite and topazine mineralization, represent the final phase of pluton. These granites differ from the Perga ones by their low content of rare metals. The Kamennaya Mogila complex lies in the southeastern part of the Ukrainian shield. It consists of biotite and muscovite-biotite, medium- and coarse-grained (also porphyric, and occasionally greisining) granites with rare metal mineralization (cassiterite, columbite, molybdenite, wolframite and beryl). Granites form several stocks (5-30 km2) situated 10-30 km to the west-northwest of the South-Kalchik gabbro-syenite-granite pluton. Granitoids in both of these complexes have similar isotopic ages (1800 Ma). Leucocratic subalkaline granites (the Novoyanisol type) are known within the pluton itself, occupying an intermediate position between the above mentioned in terms of mineral and geochemical composition. The gabbro-syenite-granite formation of the Nearazov region has a substantial similarity to the anorthosite-rapakivi-granite formation. In this respect the relation of each of them to rare metal granites is rather remarkable. This relation is, most probably, not only spatial, but also genetic. The typical rare metal granites are situated not in the parent plutons but at some distance from them.