The paper analyzes the lithology and geochemistry of seafloor sediments in the southeastern part of the East Siberian Sea. Based on the geochemical and granulometric composition, element ratios (Si/Al, Ti/Al, Fe + Ti, Mn/Al, Mn/Fe, V/(V + Ni)), and organic carbon and methane (CH4) content, the studied water area is divided into four lithological and geochemical zones. The correlations between sea depth and geochemical indicators are established as a result of single-factor dispersion and one-dimensional regression analyses. The sedimentation processes are affected by redox conditions. Particular attention is paid to anaerobic sedimentation conditions and OM distribution in seafloor sediments in the southeastern part of the East Siberian Sea.
Current estimates of the oil source potential of the Permian deposits of the Yuryuzan–Sylva Depression of the Cis-Ural Foredeep are based on geological structural models created using data obtained at the end of the XX century and require revision and updating based on new geochemical data and modern technologies. The contribution of the Permian source strata and their generation potential are not fully understood. The aim of this paper is to investigate the lithology and geochemistry of organic matter in the Permian potential oil and gas source strata, to review the results of basin modeling and to evaluate the potential for oil and gas generation within the Yuryuzan–Sylva depression of the Cis-Uralian Foredeep.
The adsorption of cadmium ions on the surface of natural talc has been studied. The relationship between the adsorption value and pH of the solution has been established at 25°C. It has been shown that maximum absorption of cadmium from the solution occurs at pH 7–8. Adsorption is the most intense for the first 5 min; the adsorption equilibrium is achieved approximately 40 min after the mineral/solution contact. It has been established that the chemical interaction of cadmium ions with the talc surface contributes to the overall rate of the process; this is supported by the consistence of the experimental data and the pseudo-second-order kinetic model. Adsorption isotherms are the most adequately described by the Freundlich model, which indicates the heterogeneity of the surface adsorption sites with variable energy. The effective sorption of cadmium ions by talc makes it possible to use talc as a sorbent for the treatment of natural and industrial waste water over a wide pH range.
The paper provides an original isotopic composition of a water phase of mud volcanoes, which are located in the southern part of the West Kuban Trough. For the first time, the δ17O, δ18O, and δD isotope ratios are determined for free and clay-bound water fractions, which were experimentally extracted by direct evaporation from clay volcanic pulp at 105 and 350°C. Our results indicate the absence of a significant contribution of dehydration waters, which are released during the smectite–illite transformation, to the overall water budget of mud volcanoes of the Kerch–Taman region. The water phase of the studied mud volcanoes mainly form due to mixing of infiltrating meteoric waters, seawater, and absorbed clay water extracted at substrate heating up to 150°C.
This paper presents the results of biostratigraphic studies of Turonian–Coniacian deposits widely distributed in the eastern Peri-Tethys. Despite extensive previous study, problems related to their stratigraphic subdivision remain insufficiently resolved. Changes in foraminiferal assemblages within this interval and their significance for zonal subdivision are examined.
A huge ammonite Parapuzosia (Austiniceras) austeni (Sharpe, 1855) was found in the Cenomanian deposits on Mountain Kremennaya (Bodrak River basin, southwestern Crimea). In addition, another fragment of a large ammonite was found in the lower Cenomanian deposits near the Crimean geological training ground of the Lomonosov Moscow State University in the 1980s. This fragment was previously found in old collections and identified as Parapuzosia (Austiniceras) cf. austeni (Sharpe, 1855). This is the second time that such an ammonite has been found in Crimea.
A comprehensive study was conducted on the chemical composition of 12 spring waters from the Shchyolkovo Urban District (Moscow Region). Hydrochemical parameters (СOD, pH, electrical conductivity) and concentrations of major ions (Ca2+, Mg2+, Na+, K+, NH_4^ + , HCO_3^ - , Cl–, SO_4^2 - , NO_3^ - ) were determined. The waters are characterized by low mineralization (0.1–0.7 g/L) and total hardness up to 8 meq/L, with calcium and bicarbonate ions predominating. The СOD values for several springs ranged from 16 to 40 mgO/L. The chemical composition of spring waters is influenced by the infiltration of atmospheric precipitation through layers of recent sediments subjected to anthropogenic impact. Integral indexes (WQI,
This paper is focused on the gold–bismuth telluride mineralization from the Losikha prospect in the Western Chukchi Peninsula, which exhibits many features typical of the intrusion related gold deposits. The mineralization includes quartz–scheelite, sulfide, gold–bismuth telluride, and supergene mineral assemblages. It is assumed that a high Te activity at the beginning of the formation of gold-bearing assemblage resulted in the complete replacement of the early native bismuth by Bi tellurides or direct crystallization of tellurobismuthite. The formation of Bi tellurides resulted in the absence of native bismuth and crystallization of high-fineness native gold rather than maldonite.
The features of the transformation of coal-mining regions under the influence of mining over nearly three centuries are analyzed and systematized, including the composition of technogenic ecological–geological systems of man-made ground masses and their transboundary impact on residential areas. Based on an analysis of the resource potential of these systems and both published and newly obtained data, it can be concluded that achieving national goals aimed at creating comfortable living conditions for populations in areas adjacent to historical coal-mining territories requires the implementation of domestically developed and tested nature-based reclamation technologies. These should be based on an integrated approach combining the theory and practice of technophytocenosis formation, the concept of ecological functions of the lithosphere, and the methodology of ecological–resource mapping. Together, these approaches enable the systematization and coordination of environmental and socioeconomic problem solving.
Technogenic formations resulting from the extraction and processing of solid mineral resources are not merely waste, but a new class of dynamic geological bodies. This paper substantiates the necessity of applying a comprehensive lithological approach to them analogous to the study of natural formations in order to predict their evolution and assess the potential for secondary use. Using specific examples, the concept of exogenic–technogenic metallogenic provinces (e.g., Kola, Urals, Kursk) is proposed, reflecting the spatial localization and specialization of anthropogenic accumulations of mineral raw materials. The research results demonstrate that technogenic deposits are active components of the geological environment, and their study requires the development of a new scientific field, namely anthropogenic lithogenesis.
A paleogeographic model is proposed and the geological evolution of the Voronezh Anteclise in the Turonian and Coniacian is refined as a result of summarizing the numerous data. Strong facies variability, as well as a varying sedimentary thicknesses, is explained by vertical tectonic movements during the general uplift of Laurasia. The relatively shallow depth of an epicontinental basin (30–50 m) is highly sensitive to vertical tectonic movements. At amplitude of 10 m, the coastal line is shifted by tens to hundreds of kilometers and a shallow basin quickly becomes extremely shallow disintegrating on a series of isolated basins, which are surrounded by paleo-uplifts producing clastic material. During Tournasian arid climate, transgression from the Tethys Ocean came from the south and led to the accumulation of mostly carbonate deposits. During the Coniacian, transgression came from the south (warm waters; the formation of carbonate deposits) and from the north (cold waters; the accumulation of siliceous deposits); the volume of terrigenous run-off increases in humid climate.
The types of technogenic impacts of defense-industrial complexes on the components of ecological-geological systems (EGS) are described. Abiotic components of EGS of defense-industrial complexes, as well as technolithotopes and technoedaphotopes are characterized. Specific examples are used to demonstrate the influence of abiotic components of EGS of military-production complexes, military depots, and test sites in Russia and neighboring countries on the biotic components of EGS, including technomicrocenosis, technophytocoenosis, and technozoocenosis. It has been shown that changes in the abiotic component of EGS of defense-industrial complexes lead to a reduction in the abundance of microorganisms and a suppression of vital processes in plants when soils and grounds are contaminated with rocket fuel. This also can result in hearing loss in fighter-bomber pilots due to man-made acoustic anomalies, as well as death of people and all living things when the technogenic thermal events and subsequent fires during explosions under takeoff of launch vehicles.
The following stages of development have been identified in the geological history of the Arctic Ocean. (1) Barremian (Aptian)–Albian ( 125–100 Ма). Formation of the Alpha-Mendeleev volcanic-tectonic rise and associated basins such as Podvodnikov, Маkarov, Stefansson, etc. Маgmatic complexes such as Seaward Dipping Reflectors (SDR) are typical of both the Alpha-Mendeleev Rise and the basins. There was strong stretching of the continental crust, but no rupture occurred. Tectonics were in an intraplate regime. Geodynamics can be explained by the presence of hot material in the mantle. (2) Late Cretaceous (100–70 Ма). The main phase of the Canada Basin opening. The basin has opened as a back-arc basin associated with the Pacific subduction zone. The passive margin of the Canada Basin for the Northwind Ridge slope is characterized by SDR-type magmatic complexes with a probable age of about 125–100 Ма. (3) Late Cretaceous–Paleocene ( 70–56 Ма). Intraplate rifting affected parts of the Canada Basin, the Stefansson Basin, the Laptev Sea region, and the area of the future Eurasian Basin. A large number of normal faults formed across this extensive territory. In the Amerasian Basin, we identify the Northwind-Sever rift system (from the Chukchi Borderland to Sever Spur on the Canada margin). (4) Eocene–Quaternary (56–0 Ma). The Eurasian Basin opened gradually. At the same time, between 45 and 34 Ma, many normal faults developed in the Alpha-Mendeleev Rise area. Numerous normal faults also formed during the Neogene.
The article addresses a topic that is currently both highly relevant and rapidly developing worldwide, namely geothermal prospecting and exploration. It presents an overview of current trends in geothermal energy, including global geothermal power generation, areas of application, and investment patterns. A brief overview of geothermal development in Russia is also provided, highlighting key regions with high geothermal potential in the context of their geological structure. Using the Mutnovsky block in Kamchatka—currently the region with the largest geothermal power generation capacity—as a case study, the paper analyzes the specifics of exploration planning. Geological risks are examined, and the features of constructing geological models of geothermal fields are demonstrated as a means of minimizing these risks and developing an effective exploration strategy under the geological conditions of Kamchatka. It is shown that a key aspect of geothermal field analysis is an interdisciplinary approach that simultaneously takes into account geological, geophysical, hydrogeological, and tectonic factors.
This study addresses the topical issue of non-destructive tree-trunk diagnosing using ground-penetrating radar (GPR) tomography. The primary goal is to identify dynamic attributes in non-processed GPR data that can reliably indicate the presence of decay or air cavities within tree trunks. The study is based on GPR tomography data obtained from 22 large trees in Gorky Park, Moscow. The proposed “attenuation multiply to distance” attribute effectively distinguishes between healthy and decay-affected trees. For healthy trees, this attribute exhibits positive values, while for decay-affected or hollow trees, the values are negative. The obtained results open new perspectives for non-destructive diagnostics of trees in urban areas and can be applied to large-scale screening of green spaces.
The Upper Kolyma gold province, which was discovered in the early 20th century, has produced more than 3000 tons of gold from placer deposits. This precious metal allowed to partially support financially the industrialization of the USSR in the 1930s and it was also used to pay for Lend-Lease supplies during the Great Patriotic War. In the 21st century, although gold continues to be extracted from placer deposits, the main source of gold production in the Kolyma region is hardrock deposits. At different periods, self-educated gold prospectors and professional geologists, who graduated from Leningrad and Moscow universities have made significant contributions to the development of this world-class gold province.
This paper reviews the structure and formation history of the Chilekta plutonic massif, located in the East Magnitogorsk zone of the Southern Urals. The pluton is composed of plutonites of two complexes, the Krasninskii (tonalite series) and the Chilekta (subalkaline series). The Chilekta complex of monzodiorites, granosyenites, and moderately alkaline granites was identified for the first time, its isotopic age (380 Ma) was confirmed by U–Pb dating (LA-ICP-MS) on zircons. The Chilekta pluton was formed as a shear magmatic duplex on the NE-trending left-lateral strike-slip fault.
Geological studies of the Natib and Mariveles volcanoes of the Luzon Island Arc, which is part of the Philippine Mobile Belt, have been carried out. New data on the stratigraphy of volcanic and volcanogenic-sedimentary Pliocene–Quaternary deposits have been obtained. Detailed geological maps of volcanoes have been compiled on the basis of geological mapping and decoding. The maps differ significantly from those available at the beginning of the research. The history of volcano formation, dynamics of volcanism during the Pleistocene–Holocene, and the geodynamic features of the volcanic zone have been considered.
Geochemical characteristics and normalized patterns of rare earth elements (REE) have been studied in 16 water samples collected from rivers and lakes in temperate and boreal regions of Russia. It is shown that the studied waters exhibit a typical REE pattern, with light REE being more abundant than heavy REE. The positive correlations between REE concentrations and dissolved organic carbon and iron in lake waters are moderate to high, indicating a potential role of organomineral colloids in REE transfer. Anomalies of Ce due to its oxidation on the surface of Mn oxides and Fe oxyhydroxide colloids and of Eu, which is associated with the contribution of groundwater to the nutrition of the studied rivers and lakes, are recorded in some of the studied reservoirs.
The composition and purpose of the main types of engineering surveys for construction are discussed including engineering-ecological surveys. It is explained that the soil massif should be considered as an ecological-geological system, which is a specific volume of the lithosphere containing biota that functions within it and on its surface. The composition and structure of this system, and the position of the lithospheric block as a lithotope in the structure of the ecosystem are described. Ecological functions of the lithosphere and types of geologic indicators studied in the process of engineering-ecological surveys and assessment of ecological-geological systems and ecosystems are discussed. The role of geologic objects, including significance of modern geologic processes within the context of modern engineering-ecological surveying is also evaluated.
