East European Platform Research Articles

The Genus <i>Alatyroceras</i> gen. nov. (Ammonoidea: Cardioceratidae, Arctocephalitinae) from the Upper Bathonian (Middle Jurassic) of the Russian Platform

A new genus Alatyroceras is established for the species A. nageli (Mitta) (type species of the genus), A. keuppi (Mitta), A. efimovi (Mitta), and A. infimum (Gulyaev et Kisselev), in Central Russia characterizing the interval correlated with the Upper Bathonian Variabile and Calyx zones of East Greenland. According to the refined data, the Keuppi Zone of the Russian Platform includes (from bottom to top) the efimovi, nageli, and keuppi faunal horizons. The genus Alatyroceras [M] completes the phylogenetic lineage Arcticoceras → Alatyroceras in the subfamily Arctocephalitinae; the name Costacadoceras Rawson is common to all microconchs of the subfamily.

Rare Earth Elements in Fe oxyhydroxides from biofilms containing iron-oxidizing bacteria

Fe oxyhydroxides extracted from modern-day biofilms with iron-oxidizing bacteria Arthrobacter spp., Gallionella spp и Leptothrix ochracea in the north-west of the East European platform display the enhanced content of rare earth elements – up to 1100 ppm. REE concentration in bacterial oxyhydroxides increase by one order in magnitude during 1 year suggesting the high sorption capacity of newly formed Fe mineral phases. La/YbN, Ce and Y anomalies in bacterial oxyhydroxides are consistent with geochemistry of the surface water facies where bacterial communities live. Isotopic composition of Nd in studied bacterial oxyhydroxides is controlled by the lithology of the Q-R underlying sediment and ambient water. 143Nd/144Nd values in Fe minerals of bacterial origin vary from 0.511570 to 0.512220 (eNd(0) from –21.8 to –9.2), the high proportion of radiogenic Nd is typical for the samples located on platform cover with Palaeozoic carbonate sediment.

PALEOZOIC INTRAPLATE MAGMATISM OF THE EAST EUROPEAN PLATFORM: COMPARATIVE ANALYSIS OF THE PRIPYAT-DNIEPER-DONETS RIFT ZONE AND THE KOLA-ARKHANGELSK PROVINCE

This paper presents a comparative analysis of geochronological, geochemical, Sr-Nd isotopic data and geodynamic conditions for the Devonian magmatism of the East European Platform, using as an example the Pripyat-Dnieper-Donets rift zone in the south of the platform and the Kola alkaline province in the north.The Late Paleozoic rifting in the south of the platform was accompanied by magmatism, which formed a wide range of rocks, from alkaline-ultramafic lamprophyres and orangeites, non-diamondiferous kimberlites and carbonatites to typical tholeiites, trachyandesites, and trachyrhyodacites. Activation of rifting processes in the north of the platform has also produced a compositional diversity of magmatic occurrences dominated by kimberlites, in particular diamondiferous (Arkhangelsk diamond-bearing province), which is the main distinctive feature of the place. The Pripyat-Dnieper-Donets rift zone is subject to reverse lateral geochemical zonality of the mantle sources – from those depleted in the axial zone of the Dnieper-Donets trough to more enriched in the marginal parts – trough shoulders (Azov region, Voronezh crystalline massif): along the southeast to northwest axis of the rift zone to the Zhlobin saddle (orangeites, alkaline picrites of the Zhlobin alkaline-ultramafic complex) and in the Pripyat trough (Pripyat alkaline and subalkaline mafic complex) as well was perpendicular to the axis from the central part of the Dnieper-Donets trough to the southwest towards the Eastern Azov region (non-diamondiferous kimberlites) and to the northeast towards the Voronezh crystalline massif.Currently available petrological-mineralogical and isotopic-geochemical data on magmatites of both large magmatic structures suggest significant lithospheric heterogeneity, different types of sources of formation of rocks, and a significant influence exerted by the crustal component both in the southern and northern parts of the East European platform.

A New Earthquake in the Central Part of the East European Platform (in the Vicinity of Rybinsk)

A New Earthquake in the Central Part of the East European Platform (in the Vicinity of Rybinsk)

Oil and gas potential of ancient Riphean sediments of the East European Platform (Mezen syneclise) based on basin analysis

Oil and gas potential of ancient Riphean sediments of the East European Platform (Mezen syneclise) based on basin analysis

Геохимические и типологические особенности детритовых цирконов сосновской толщи палеогена (Русская плита)

The Paleogene Sosnov Formation is represented by glass quartz sands which are widely occurred in the eastern part of the Russian Platform. Interest in Paleogene quartz sands in Russia is increasing due to the growing needs of the glass industry. But by now, the mineral resource base of glass raw materials in the European part of Russia is of almost complete exhaustion. In recent years, the comprehensive study using modern mineralogical and geochemical methods is undertaken resulting in substantiation of the injecting mechanism of formation of Sosnov quartz sands. The current paper presents the results of the study of morphologic and geochemical features of detrital zircons extracted from the sands of the Paleogene Sosnov Formation and the Bathonian Lukoyanov Formation. The latest can be proposed as a source layer for the Paleogene sand injectites. It has been determined that zircons from both strata are of the same Pupin`s morphological types and regarded to be originated from predominantly intermediate, mafic, and rarely felsic rocks. The Puchezh-Katunk endogenous structure is suggested to be the most probable source area. The assumption that the Bathonian Lukoyanov sandstones are the most probable source for the injection of the Paleogene sands is confirmed.

Строение центральной части палеопротерозойского Лосевского террейна по данным плотностного моделирования

The results of detailed three-dimensional density modeling of the upper crust of the central part of the Losevsky terrane located in the northern part of the Voronezh crystal massif are considered. The distribution of absolute crustal density values of to a depth of 16 km was obtained as a result of the inversion of local anomalies of the gravitational field in the Bouguer reduction. The solution of the inverse problem of gravimetry was implemented within the framework of the initial model, which was formed using digital geological and geophysical data from the study area: the regional density model of the East European Platform lithosphere and its corresponding regional gravity field; the field of local gravity anomalies, representing the difference between the observed and regional fields of the lithosphere model; generalized information on the density of sedimentary cover rocks and the crystal basement; the thickness scheme of the «gravity-active» layer, obtained on the basis of statistical analysis of the anomalous field; geological and topographic information. Quantitative interpretation of the gravimetry data allowed us to obtain fundamentally new information about the geological structure of the upper crust of the study area. The reliability of the obtained results is confirmed by the consistency of a priori data and the correspondence of the total model (local plus regional) and observed gravitational fields.

New findings of the Ginkgoales in the Middle Jurassic of the East European platform

Representatives of ginkgoaleans from the Middle Jurassic of the Stoilensky opencast mine in the Belgorod Region and the Mikhailovsky opencast mine in the Kursk Region, European Russia are described for the first time. Remains of ginkgoaceous affinity dominate in some samples and are represented by leaf fragments of Sphenobaiera angrenica (Samylina) Nosova, originally described from the Middle Jurassic Angren Formation in Uzbekistan where they are associated with female reproductive structures (collar complexes) of Nagrenia samylinae Nosova. Rare fragments of the collars were also found in the Stoilensky mine. These remains are assigned to Nagrenia sp. As well as in the Angren Formation, seeds of Allicospermum budantsevii Gordenko are recorded in the Stoilensky mine.

The Moscovian–Kasimovian boundary problem in the Northern Urals: A case study of the Moleben-Iz Section, Ilych River

The Kasimovian lower boundary is usually determined by the first appearance of Obsoletes and advanced Protriticites fusulinids; however, this criterion is not always met. In the northern part of the Urals and Pai-Khoi, the Moscovian–Kasimovian boundary is determined by the abrupt appearance of fusulinids of the Subfamily Pulchrellinae. In this paper we present results of our study of the Moleben-Iz section, in an attempt to define the Moscovian–Kasimovian boundary. In this section, the upper Moscovian and lower Kasimovian deposits are represented by shallow-marine carbonates, including a diverse fusulinid complex. The most important stratigraphic level here is the lower part of bed 6, characterized by the abrupt appearance of the fusulinids Kanmeraia, Eowaeringella and Dagmarella. This level is also associated with the diversification of Usvaella (species U. plicata (Shamov and Shcherbovich) and U. porifera Remizova appear) and Pulchrella (Pul. whitensis (Ross and Sabins), Pul. hayasakai (Watanabe), and Pul. pokojamensis (Lebedeva) appear). The later appearance of Obsoletes obsoletus may be related to the later migration of this species from the Russian platform to the Urals. Placement of the Kasimovian lower boundary in the Northern Urals and Pai-Khoi at the base of the Kanmeraia ozawai-Usvaella usvae Biozone allows us to correlate this boundary with the Missourian base of the North American continent.

Thermal State and Thickness of the Lithospheric Mantle Beneath the Northern East-European Platform: Evidence from Clinopyroxene Xenocrysts in Kimberlite Pipes from the Arkhangelsk Region (NW Russia) and Its Applications in Diamond Exploration

This paper presents the reconstruction of the architecture of the lithospheric mantle, including its thermal state and thickness, as well as the scale and efficiency of its sampling by four kimberlites from the Arkhangelsk diamondiferous province: Arkhangelskaya, Lomonosovskaya, V. Grib, and TSNIGRI-Arkhangelskaya. These kimberlites differ in terms of their composition, diamond content, and location. Data presented include the major-element composition of clinopyroxene xenocrysts (>2000 grains), P–T calculations from compositionally filtered Cr-diopside grains, and the reconstruction of local paleogeotherms. Additionally, we used available data on Ni content in peridotitic garnet xenocrysts to calculate their T values and project them onto local Cr-diopside-derived geotherms to reconstruct the vertical distribution of mantle xenocrysts and assess the efficiency of lithospheric mantle sampling by different kimberlites. We identified the presence of a >200 km-thick lithospheric mantle beneath the region at the time of kimberlite emplacement. We also found that the diamond content of the studied pipes was, to some extent, dependent on the following set of factors: (1) the thermal state of the lithospheric mantle; (2) the width of the real “diamond window” marked by mantle xenocrysts, especially by diamond-associated garnets; and (3) the efficiency of lithospheric mantle sampling by kimberlite. The results of this study can be used to inform diamond exploration programs within the region.

U-Pb AGE OF ZIRCONS FROM PALEOPROTEROZOIC SECONDARY QUARTZITES OF THE BOLSHOI TYUTERS ISLAND AND FROM SANDY MATRIX OF EARLY RIPHEAN CONGLOMERATES OF THE GOGLAND ISLAND (GULF OF FINLAND): FEATURES OF THE PRE-RIPHEAN HIATUS IN SEDIMENTATION IN THE NORTHEAST OF THE EAST EUROPEAN PLATFORM

The paper presents the results of U-Pb isotope dating of zircons extracted from rocks of the southern part of the Baltic Shield (Early Riphean conglomerates and Paleoproterozoic secondary quartzites) and makes a comparison of these results with the ages of crystalline complexes of the East European Platform (EEP). The paper presents the study results on composition of quartzites from the Bol. Tyuters and Gogland islands. There has been discussion about tectonic and paleogeographical features in the period prior to the beginning of Riphean sedimentation in the northeastern part of the EEP. It is concluded that the conglomerates are composed of erosional products of mainly Paleoproterozoic and less frequently Archean crystalline complexes. At the same time, the rocks at the base of the generalized section of Riphean deposits (Gogland group), did not contain any zircons with ages referring to 200 million years prior to the inferred time (1640–1660 Ma) of the beginning of the conglomerate sequence formation. The rocks that compose the Gogland group and their underlying Paleoproterozoic basement rocks have significant differences. We associate these differences with the existence of pre-Riphean sheet-like deposits, comprising rocks of essentially quartz composition, in the southern Baltic Shield, in the upper levels of the peneplenized Paleoproterozoic basement structure. The deposits relics are only found on the Bol. Tyuters Island; in all other places, these deposits were completely eroded or underwent significant structural and material transformations. The absence of detrital zircon grains with ages ranging from 1.87 to 1.65 Ga in the clastic rocks of the Riphean basal horizons implies no noticeable Pre-Riphean and Early Riphean orogenic movements in the northeastern part of the EEP. Tectono-magmatic reactivation in this region occurred only in the middle of the Early Riphean.

Findings from Deep Magnetotelluric Studies in the Sloboda Geodynamic Intersection (East European Platform)

Findings from Deep Magnetotelluric Studies in the Sloboda Geodynamic Intersection (East European Platform)

On the moss genus Gomankovia from the upper permian of the Russian platform

On the moss genus Gomankovia from the upper permian of the Russian platform

Sources of Fine-Grained Aluminosiliciclastics for the Vendian and Early Cambrian Deposits of the Western Part of the East European Platform: Some Lithogeochemical Constraints

Sources of Fine-Grained Aluminosiliciclastics for the Vendian and Early Cambrian Deposits of the Western Part of the East European Platform: Some Lithogeochemical Constraints

MOSCOVIAN FUSULINIDS (FORAMINIFERA) FROM SE TUNISIA: THE CASE OF KR-1 KIRCHAOU BOREHOLE (TATAOUINE AREA)

Moscovian (Middle Pennsylvanian) deposits with mixed oolitic and fossil-rich carbonates have long been known from the Kirchaou KR-1 borehole in SE Tunisia. However, its biostratigraphy has never been investigated in detail. This study is mainly dedicated to reviewing the late Bashkirian and Moscovian successions, and characterizing the late Moscovian-early Kasimovian boundary interval. The important fusulinoid faunas of the Middle Pennsylvanian interval within the 315.5-meter-thick KR-1 borehole mainly include staffellines, eostaffellines, millerellines, pseudostaffellines, and Fusulinoidea, which are first illustrated here. The distribution of the main index taxa allows us to distinguish four foraminiferal biozones: (1) the Tikhonovichiella tikhonovichi - Profusulinella Zone of the Melekessian-Vereian (latest Bashkirian-earliest Moscovian), (2) the Beedeina – Citronites Zone of the Kashirian (late early Moscovian), (3) the Taitzehoella prolibrovichi – Fusulina of the Podolskian (early late Moscovian), (4) the Protriticites - Quasifusulinoides Zone of the Myachkovian - Krevyakinian (late late Moscovian – early Kasimovian). The Moscovian - Kasimovian transition is mainly characterized by Protriticites, Quasifusulinoides, Montiparus, Topilinia, Beedeina, Fusiella, Profusulinella, and Fusulinella taxa. The study of fusulinoid assemblages allows reliable correlations with coeval associations from the Russian Platform, Southern Urals, Western Europe, Spain, and Donbas (Ukraine)

New Ostracod Genera Bathoniella (Bathonian and Lower Callovian of the East European Platform and Northern Germany) and Parabathoniella (Lower and Middle Bathonian of Scotland). Part 1: Taxonomy

New Ostracod Genera Bathoniella (Bathonian and Lower Callovian of the East European Platform and Northern Germany) and Parabathoniella (Lower and Middle Bathonian of Scotland). Part 1: Taxonomy

Quartzites of the Khobeinskaya suite of the Subpolar Urals: Material composition, age limitations and possible sources of terrigenous material

Research subject. Quartzites that make up the ridge part of the ridge Rosomaha in the northern part of the Lyapinsky meganticlinorium in the Subpolar Urals. Material and methods. Detrital zircons were isolated from quartzites and their optical and isotope-geochronological U-Pb (LA-SF-ICP-MS) studies were performed. On the basis of chemical analyzes of rocks using indicator ratios and coefficients, the conditions for the formation of deposits were established. Results. The stratigraphic position of the quartzite ridge Rosomaha was determined. The time and conditions for the formation of the Khobeinskaya formation were specified. The role of polymetamorphic complexes of the Subpolar Urals as possible sources of terrigenous material removal during the formation of the Upper Precambrian section of the Subpolar Urals was estimated. Conclusions. It was established that the quartzites belong to the ridge Rosomaha to the Khobeinskaya formation, whose age is limited to the interval of 850–800 Ma (Inzersky level). It is shown that the crystalline complexes of Fennoscandia and the Central Russian orogen, as well as polymetamorphic complexes of the crystalline basement of the Timan-Severoural margin of the East European Platform, could be sources of terrigenous material.

The Formation Conditions of the Volga Basin Oil Shales in Relation to Their Metallogeny on Rhenium and Other Valuable Elements

The Volga oil shales are located on the Russian platform and represent a potential non-traditional and promising source of rhenium and other valuable metals. Concentrations of rhenium at the level of industrial types of ores have been identified at the Perelyubskoe and Kotsebinskoe deposits. The complex of lithological and geochemical studies suggests that the metallogeny of the Volga oil shales is associated with the influence of volcanism and anoxic conditions during the sedimentation period. The main criteria have been identified by which high concentrations of rhenium in the Volga oil shales can be predicted: the content of organic carbon, molybdenum, and the DOPr indicator. Based on the analyzed data, promising layers have been identified for the Perelyubskoe and Kotsebinskoe deposits to detect industrial concentrations of rhenium.

The use of magnitomineralogical methods to develop a model for the formation of non-marine microbial limestone of the red-coloured kazan stage (middle permian) of the lower Kama (east-european platform)

The use of magnitomineralogical methods to develop a model for the formation of non-marine microbial limestone of the red-coloured kazan stage (middle permian) of the lower Kama (east-european platform)

Results of the study of the section of the Takata formation "Yuzhnaya Rassolnaya" in the territory of the Poludovo-Kolchimsky anticlinorium of the Western-Ural folding zone (Krasnovishersky district, Perm territory)

Relevance. Relationship with the Takata formation of diamond reservoir rocks and previously discovered deposits and the presence of prospects for discovering new ones in the zone of the forward folds of the Urals. Aim. To reconstruct the conditions of sedimentation and composition of rocks, the source of the removal of terrigenous rocks of the Takata formation based on the results of studying the "Yuzhnaya Rassolnaya" section. Objects. Terrigenous rocks of the Takata formation in the "Yuzhnaya Rassolnaya" section located in the western part of the alluvial diamond deposit "Yuzhnaya Rassolnaya" in the Krasnovishersky district of the Perm Territory. Methods. Lithofacies analysis, petrographic study of thin sections in transmitted light using crossed nicol methods, determination of the content of rock-forming oxides by X-ray fluorescence on an S8 Tiger (Bruker) spectrometer, analysis of rock-forming elements on glassy disks. Impurity and microimpurity elements (with a content of <5%) were determined using a certified method for defining elements by inductively coupled plasma mass spectrometry according to the method, STO TGU 048-2012. The analysis was performed by ICP-MS on an Agilent 7500cx quadrupole mass spectrometer (Agilent Technologies Inc., USA) using an internal (In Internal standard, Inorganic Ventures, USA) and an external standard SGD-2A (GSO 8670-2005). Results. Lithological-facial, mineralogical, petrographic, lithogeochemical studies of Takata terrigenous deposits were carried out in the "Yuzhnaya Rassolnaya" section in the area of the Polyudovo-Kolchima anticlinorium of the Western Ural folding zone, which made it possible to clarify the sources of matter and sedimentation conditions. The formation of sediments occurred in a transitional sedimentation environment. A transgressive sequence is observed from bottom to top. Terrigenous rocks of the Takata formation include rocks of the first and second sedimentation cycles. They were cut off due to the destruction of primary igneous (acidic and basic compositions) and metamorphic rocks, as well as sedimentary rocks. The totality of the material characteristics of the terrigenous rocks of the Takata formation, taking into account the published data, allowed us to assume that sedimentation of the rocks occurred on the passive continental margin, with the supply of clastic material due to the erosion of internal raised blocks of the foundation of the East European Platform. The activation of the latter occurred in the Emsian time with the manifestation of general lithospheric folding. At the same time, water flows carrying weathering products from the East European Platform eroded sedimentary rocks of the Riphean, Vendian, Ordovician and Silurian, which fragments we observe in small quantities when describing thin sections.