Abstract The native gold in the Woxi Au–Sb–W deposit is characterized by remarkably high purities (99.9%), called as super-pure native gold. The deposit can thus be used as the suitable application example for analyzing ore-forming conditions by using the thermodynamic calculation of AuxAg1 – x-fluid equilibria. According to experimental results of minerals and fluid inclusions, some physicochemical

Abstract The paper presents data on noble-metal mineralization in carbon-bearing rocks of the Sarma Group in the southern flank of the Baikal inlier of the Siberian craton basement. The phase composition of the accessory ore minerals (pyrite, arsenopyrite, microinclusions of native Ni, Sn, Zn, Cu, Fe–Ni and Ni–Fe–Ti composite compounds, Cu and Pb sulfides, rutile, monazite, zircon, and barite) were

Abstract Surma Basin in Northeast India is characterized by a thick Cenozoic sedimentary succession that initiated due to the collision between Indian and Burmese plates. Variability in the litho-association of a thick sedimentary column in this robust terrain represents the distribution and deposition of enormous sediments that supplied throughout the entire basin evolution, especially during the

Abstract The paper summarizes data on germanium and gallium concentrations in natural magmatic melts as follows from analyses of mineral-hosted inclusions and quench glasses in volcanic rocks. Germanium concentrations in melts vary from 0.96 to 17.6 ppm (1472 determinations). The geometric mean germanium concentration in silicate melts is 1.56 ppm, which is quite close to the clarke value. Concentrations

Abstract Changes in the elemental composition of asphaltenes in organic matter (OM) of different origin, with particular focus on their evolution from proto- to mesocatagenesis, were analyzed in samples of Devonian bituminous shales and brown coals from the Kuznetsk Basin and samples of Cenozoic brown coals and clays from the Middle Amur Basin. The composition of asphaltenes (protoasphaltenes) of different

The paper reports petrochemical and isotope data on the ferromanganese ores and host volcanosedimentary rocks of the Taloi–Usoi interfluve of the Ikat terrane, the Central Asian Fold Belt. Obtained data indicate that the formation of the Taloi ferromanganese mineralization was related to the explosive and volcanic activity of synsedimentation suprasubduction volcanism. The age of the volcanogenic rocks

Abstract The paper presents author’s original and literature data on the standard free energy of 31 Sc ions and complexes in aqueous solution. Scandium behavior at the weathering of phyllite shales is physicochemically simulated with the Selector program package. The content of Sc in the shales is close to its average content in the Earth’s crust: 10–3 wt %. Solution in the weathering profile was determined

The natural basic aqueous aluminum and iron sulfate, aluminocopiapite (Al0.60\({\text{Fe}}_{{0.07}}^{{3 + }}\))\({\text{Fe}}_{{4.00}}^{{3 + }}\)[SO4]6.03(OH)1.95 ⋅ 19.54H2O (Blyava, South Urals, Russia), was studied using powder X‑ray diffraction, infrared and Mössbauer spectroscopy, and thermal analysis. The enthalpy of formation from the elements \({{\Delta }_{f}}H_{{el}}^{0}\)(298.15 K) = −11 826

Abstract The paper presents data on amphibolites dredged during Cruise 249 of the German R/V Sonne at three sites: one at the northwestern termination of the Stalemate Ridge (ocean-side slope of the Aleutian Trench) and two at the western slope of the north Shirshov Rise (in the western sector of the Bering Sea). Data on the petrography and geochemistry of the amphibolites and their estimated P–T metamorphic

The distribution of composition fields of syn-rift and syncollisional sandstones and fine-grained clastic/clayey rocks of various structures and different ages are compared on the SiO2–K2O/Na2O, F1–F2, and DF1–DF2 diagrams. Syn-rift sedimentary sequences fill intraplate rifts, rifts at divergent, conservative and convergent plate boundaries, as well as their triple junctions. Syncollisional sediments

Abstract The relationship between soil cave development and the chemical characteristics of groundwater in a karst area was investigated. The purpose of the investigation was to identify potential soil caves and predict their collapse. Field surveys and monitoring were carried out, and statistical analysis, and geological comparison methods were used to analyze the relationships between Ca++, HC\({\text{O}}_{3}^{

Abstract— Oxygen isotope composition was studied in 33 monomineralic fractions of olivine from plagioclase lherzolite, dunite, troctolite, and olivine gabbronorite of the Yoko-Dovyren layered massif. The δ18O values of the least altered rocks not contaminated with crustal materials range within 5.8 ± 0.2‰ (n = 27). These values for the dunite contaminated with carbonate material are notably higher

Abstract— The paper presents isotope–geochronological data on zircons from a granite–aplite dike that cuts garnet–hypersthene gneisses of the Kuzeyev unit of the Neoarchean–Paleoproterozoic Kan Group in the southern extension of the Ishimba–Tatarka regional shear zone, Kan River. The morphology and internal structure of most of the zircon grains indicate that the zircons are metamorphic and xenogenic

Abstract The variance and regression analyses were applied to study the distribution and relationships between organic carbon, calcium carbonate, abiogenic matter, biogenic silica, and their accumulation depth in the upper Pliocene sediments in different structural zones of the Indian Ocean. Analysis of variance allowed us to quantify the influence of diverse facies settings on the distribution of

We carried out equilibrium-kinetic modeling the interaction of the integrated technological sample from the Pavlovskoe ore deposit with atmospheric precipitates to estimate the potential environmental contamination during mining. Accumulation of major (Zn, Pb) and trace (Cu, Co, Cd, As, Hg, Se, Hg, Sb) ore elements in aqueous solution during summer period has been calculated. It has been shown that

Melt inclusions were investigated in the minerals of dacite tephra of the largest Holocene eruption (7900 years) of Khangar volcano, Sredinny Range of Kamchatka. Melt compositions correspond to rhyolite (SiO2 = 70–77 wt %, Na2O+K2O = 6–7 wt %) with ~5 wt % H2O. The melts show a minor negative Nb anomaly and lesser HREE depletion (La/Yb is ~7.1) compared to those of Ichinsky Volcano, another active

Abstract— The paper analyzes methods currently used to evaluate the generation parameters of source rocks and suggests a new modified variant of the van Krevelen diagram and an original algorithm for evaluating the hydrocarbon generation properties of bitumen-bearing rocks of the Bazhenov Formation and its analogues. This is done with the application of an integrated approach that employs pyrolitic

Abstract— The paper presents data on contents of the platinum group elements (Pt, Ir, Pd, and Ru) and Au in Fe–Mn nodules of different morphology and in their separate layers from the Cape Basin, Atlantic Ocean. The Layer-by-layer analysis of the Fe–Mn nodules and crusts shows that the platinum group elements (PGE) are accumulated in the ferromanganese oxyhydroxide layers relative to the clayey nuclei

Electron microscopic studies of the surface of the spacecraft descent vehicle (DV) have revealed faceted particles of various shape and size, which are formed when the DV travels through the Earth’s atmosphere at an ultrasonic velocity. The particles are no more than 5 µm in size. An X-ray diffraction analysis of the phase composition of the precipitate on the DVs porthole after their landing showed

The paper presents experimental and numerical simulation of the bioremediation in nitrate-, -sulfate-ions and uranium polluted aquifers near the Novosibirsk Chemical Concentrates Plant (NCPP) sludge storage facility. We used two HCh 4.4 (MSU) and PHREEQC 2.18 (USGS) software packages for geochemical modeling and found that the microbial consumption of oxidizers (oxygen and nitrate ions) led to a decrease

Abstract— Diamonds were lately identified in chromitites from ophiolites and in volcanic rocks. Although the tectonic settings of diamonds found in these rocks are different, the diamonds are identical in small size, cuboctahedral habit, sets of minor admixture elements, and isotopic characteristics. A model is suggested for their formation during various stages of a single evolutionary cycle of the

Abstract This paper reports the results of the first study of pyroxenes from the deepest zones of the Lovozero deposit. The geochemical and mineralogical study of these rocks is of great scientific interest, as they are the least differentiated rocks and provide insight into the composition of a parental magma. According to microprobe analysis, clinopyroxenes evolve from early diopside–hedenbergite–augite

Abstract— The GEOCHEQ_M and GEOCHEQ_Isotope databases and codes were used to simulate the evolution of chemical interactions with time in the closed systems aqueous solution 0.495 М NaCl + 0.0194 M NaHCO3 + olivine (Fo91) at temperatures of 200 and 320°C and a pressure of 350 bar. The solution to rock mass ratios, selected temperature and pressure, the chemical composition and size of the olivine grains

Abstract— The paper presents data on the comparative assessment of the composition and properties of natural and magnetized zeolite-bearing tuffs (ZBT) from the Kholinsky, Transbaikalia, and Chuguevsky, southern Russian Far East, deposits in Russia. In addition, the composition and properties of magnetite synthesized by two methods and used for ferritization of ZBT were determined. The phase composition

Three different-age series of granitoid veins and dikes of the Baikal–Muya fold belt were studied. Two of them, plagiogranites of the ophiolite complex and the first postophiolitic plagiogranites, are associated with the suprasubduction ophiolites of the eastern Baikal–Muya belt. The third series is represented by hypabyssal tonalite–plagiogranite–leucogranite complex of the Kichera zone in the western

Abstract— This paper discusses the petrological and geochemical characteristics of the acid plutonic rocks (mainly granites of different colors) exposed in Khanak and Devsar areas of Neoproterozoic Malani Igneous Suite (MIS) to understand their magmatic evolution processes, petrogenetic history and tectonic regimes. Petrographically, granites of both areas show porphyritic, hypidiomorphic, granophyric

Abstract The paper presents the results of thermodynamic modeling of a transformation of a kerogen-bearing sedimentary rock within the temperature range of 50–400°С at a gradually increasing pressure from 300 to 2200 bar. A gradual increase in temperature and pressure, starting from 50°С, leads to the formation of the lighter and more oxidized type of kerogen. The methane–carbon dioxide gas phase is

Abstract The paper presents certain aspects of applying equilibrium-kinetic modeling to preliminarily assess the formation of the chemical composition of sewage subdump waters during upcoming mining at the Udokan deposit. The mineral dissolution rates, including oxidative dissolution of sulfides, and sorption of strontium, cobalt, zinc, and nickel on calcite are taken into account. It is shown that

Thermodynamic modeling with the HCh software complex was applied to analyze the probability of acid drainage formation during the evolution of a copper–ore deposit in low-temperature conditions (5°C) with various water levels. During the modeling, three main factors were taken into account: the percentage of pyrite in rocks, the availability of oxygen in the air, and the water content of the rocks

Abstract— A thermodynamic model of the gold–polymetallic volcanogenic massive sulfide ore-forming system, related to the evolution of a shallow acid volcanic chamber of an island arc (Galkinskoe deposit, Northern Urals) was created. The low W/R ratio (<0.25) obtained via modeling indicates slow filtration of fluid upsection in the sequence. In general, the Cu, Zn, Pb, Ag, and Au concentrations in the

Abstract Chemical interactions in carbonate rock–seawater, silty sand–seawater, clay rock–seawater, basalt–seawater, and granite–seawater systems, where the term “seawater” denotes the compositions of halite, epsomite, and sylvinite stages of seawater densification, were simulated at 25, 100, 200, and 300°С and various pressures in order to assess the ability of rocks to generate hydrocarbons. Based

Abstract The paper briefly describes some of the problems solved at the Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, to illustrate the possibilities and limitations of the promoted physicochemical computer simulation method. The computer simulation results on the formation of hydrocarbons in the Earth’s crust, acid drainage estimates, and other results of the method

Abstract The report presents extensive factual data on the chemical composition of natural waters in different regions of Central Eurasia. The features of the chemical composition of natural waters are revealed for several regions with a humid and arid climate, as well as for tectonomagmatic activation conditions. The abundance of over 50 chemical elements in natural waters is characterized. The geochemical

Abstract— The research data are presented on the chemical and isotope composition of sodium bicarbonate groundwaters in the southeast of West Siberia. It is shown that the studied waters occur ubiquitously within Mesozoic–Cenozoic sedimentary deposits at a depth roughly from 50–300 m to 1.0–2.3 km. Various geochemical characteristics and conditions of occurrence made it possible to distinguish five

Abstract— The paper presents experimental data on fluorine leaching from igneous rocks (dacite, rhyodacite, and trachyrhyolite) and greisen with distilled water and 0.01 M HCl, CH3COONa, NaHCO3, and Na2CO3 solutions. Fluorine leaching is proved to be proportional to its content in the rocks and depends on pH of the aqueous solution: the equilibrium concentrations of fluoride are minimal in the near-neutral

Abstract—Studies have shown that the concentration of heavy carbon isotope in the organic matter (OM) in the surface layer of the marine sediment increases and the amount of terrigenous OM decreases by about 1.4 times with increasing distance from the Indigirka River delta from 50 km to 600 km. This is accompanied by 1.3–2.1 times decrease of heavy metals and 1.3–1.4 times decrease of rare-earth elements

Abstract— The paper presents results of SIMS and SEM-EDS studies of the silicate minerals from one radial and one granular chondrule of the Buschhof ordinary equilibrated L6 chondrite and discusses geochemical features of the olivine, pyroxene, and plagioclase from the chondrules and matrix of this meteorite. Results show that pyroxene and plagioclase from the radial chondrule did not preserve the

Abstract Structure, defects and inclusions in natural polycrystalline ballas-type diamonds are studied by complementary techniques: Scanning Electron microscopy, cathodo- and photoluminescence, X-ray diffraction, radiography and fluorescence, infra-red spectroscopy and carbon isotope analyses. Peculiarities of internal structure of some of the samples are explained by growth of the diamonds as volume-filling

Abstract— The paper presents data on the vertical distribution of 137Cs of Chernobyl origin in arable and meadow soils to a depth of 40 cm in typical catenary junctions of predpolessie, predopolje, and opolje landscapes with a different density of 137Cs contamination 30 years after the accident at the Chernobyl nuclear power plant. Newly obtained data on the removal of 137Cs beyond the arable horizon

This paper considers the element distribution between species in the lysimetric waters and lakes of the Valdai National Park in different seasons. Seasonal studies of natural waters and element speciation in them in 2019 using membrane filtration and ion-exchange separation showed the differences in the seasonal distribution of species depending on geochemical factors. The seasonal temperature factor

Abstract— Authors’ original continuously updated database, which currently comprises data from 22 300 publications on mineral-hosted fluid and melt inclusions, is used to generalize data on the physicochemical parameters of processes that produced fluorite and barite deposits. The paper presents data on the following parameters of the fluids: temperature, pressure, density, salinity, and gas composition

Abstract Extensive field hydrogeochemical data and thermodynamic simulations demonstrate that the composition of lacustrine waters is controlled not only by evaporation but also by interaction between the waters and rocks. This interaction begins in the catchment areas of the lakes and continues in these lakes themselves, because the waters (regardless of their salinity) do not occur in equilibrium

Extremely high uranium concentrations (>100 times average crustal content) are established in the recent sediments of small lakes of the northern Murmansk region. It is substantiated that the high uranium concentrations in the sediments of the lakes of the northern Murmansk region were mainly controlled by natural uranium migration from magmatic and metamorphic rocks bearing uranium mineralization

Abstract— The paper presents the first data on the nitrogen isotope composition of the associated gases of mineral waters in the North Caucasus and newly acquired data on the carbon isotope composition of the CO2 and CH4. Most of the samples were taken from the high-\({{p}_{{{\text{C}}{{{\text{O}}}_{{\text{2}}}}}}}\) waters of the Elbrus and Kazbek volcanic areas in the Greater Caucasus. It is shown

Abstract — The paper presents data on 48 samples of crude oil and oil shows from oil fields and surface oil seeps in the Krasnodar Territory, Crimea, and the Russian part of the Black Sea. The oil samples were analyzed for isotope and molecular composition. According to the results, all crude oil samples were classified into three genetic types (Akhtyrsky, Sladkovsky, and Nikolaevsky), which differ

Numerous orogenic gold deposits of different age, scale, and mineralization type are located within Northern Transbaikalia. Among them, there is a large group of Early Permian deposits, whose sources and relationships with Late Paleozoic magmatism remain debatable. These issues were solved by the example of the middle-scale (~24 t, Au) Irokinda deposit, localized within the Precambrian rocks of the

Abstract— The model of the formation of the Earth–Moon system during the compression and fragmentation of a gas–dust cloud (Galimov, 2011; Galimov and Krivtsov, 2012) suggests an unusual mechanism for the formation of the Earth’s core. In particular, the model predicts that iron in the Earth’s core should be enriched in the light isotope, and the Earth’s mantle should be, conversely, enriched in the

Abstract The first experimental data were obtained on the distribution of boron isotopes between gas and liquid at 100–350°С and the pressure of saturated water vapor, and the effect of pH on this distribution at 100°С was studied. The results showed that the value of δ11Bgas–δ11Bliquid was 5.9, 3.7, 1.1, 0.8, and –1.3 ‰ at 100, 200, 250, 300, and 350°С. In an alkaline solution, the boron distribution

A series of photochemical experiments with sulfur dioxide were carried out using a xenon lamp (λ > 200 nm), a low-pressure mercury lamp (λ = 184.9 and 253.7 nm), and an UP-213 laser system (λ = 213 nm) as light sources. Based on the isotope data obtained for elemental sulfur (the end product of SO2 photolysis), we revealed specifics in correlations between δ34S, ∆33S, and ∆36S values depending on the

Abstract— The isotopic composition of noble gases, nitrogen, and carbon in two samples of the Ozerki L chondrite, which differ in the degree of impact metamorphism, analyzed by the methods of stepwise oxidation and crushing, is reported. The data obtained indicate that the meteorite contains gases trapped on the asteroid during the impact events. The isotopic composition of trapped argon, studied by

Abstract— The first data on the isotopic composition and elemental ratios of nitrogen, carbon, and noble gases in samples from the early stages of the formation of the Guli Complex (Maimecha-Kotui igneous province, Polar Siberia), obtained using the method of stepwise crushing, are reported. The 40Ar/36Ar ratios in the crushing steps vary from the values close to atmospheric (~296) in the meimechite

Abstract— Distinguishing between components (stomatal conductivity, mesophyll conductivity, carbon dioxide fixation in chloroplasts, and respiration) of the complex biochemical mechanism of plant photosynthesis is a challenging problem. To solve it, we used both experimental data obtained in natural conditions (time series of recorded indicators) and a specially designed experiment: determination of

Abstract Geochemical processes controlling hydrochemical evolution of shallow groundwater (<200 m) were studied in the Chahan Lake Basin, China. A combination of chemical and isotopic tracers (δ2H, δ18O, 87Sr/86Sr, 3H and 14C), along with inverse geochemical modeling were applied. Shallow groundwater primarily originates from local precipitation, and has negligible mixture with deep groundwater. Shallow

Kola nuclear power plant, which discharges warm water into one of the bays of sub-arctic Lake Imandra, significantly changes the fish habitat, creating temperature gradient from 2 to 8°C compared to water temperature in the other part of the lake. The permeation, metabolism and bioaccumulation of elements in the stenothermal cold-water species (Coregonus lavaretus L.) in warm water impact zone are

The paper reports chemical data on the atmospheric precipitation within the studied area of the Valdai National Park during monitoring in 2015–2018. The main parameters of atmospheric precipitation as well as major and trace-element compositions of waters are analyzed. Seasonal dynamics and possible pathways of element uptake in atmospheric precipitation are considered. Multidimensional statistical

Abstract— The paper presents a concept of the sustainability of aquatic ecosystems, their disorganization when impacted by anthropogenic pollution, and evolutionary development after the effect of the toxicants decreased. The general laws of the ecosystem transformations are explained from the viewpoint of the ecological theory and the mechanism of thermodynamic ordering of matter in living systems

Abstract— The concept of toxicity is analyzed from the standpoints of theoretical biogeochemistry and geochemical ecology. The phenomenon of toxicity is demonstrated to appear and be able to significantly manifest itself only as a consequence of anthropogenic disturbances of self-regulation systems and dynamic equilibria that existed in natural biogeochemical cycles throughout the whole history of

The paper addresses the removal of chemical elements by suprasoil and subsoil phytomasses of herbaceous phytocenoses and their subsequent return to soil during decomposition of plant remnants. The obtained results allowed us to evaluate the biogeochemical cycles of essential (Zn, Cu) and toxic (Pb, Cd) elements in natural biogeocenoses of the Middle Urals. It has been shown that the intensity of such

Abstract— The paper presents data on seasonal fluctuations in hydrochemical characteristics and the supply dynamics of biogenic elements in four hypersaline lakes in Crimea: Sasyk-Sivash, Oiburg, Konrad, and Sakskoe (eastern basin) in 2017. The migration pathways of biogenic elements in the hypersaline lakes are determined depending of natural and anthropogenic factors. The role of the elements in

The higher accumulation of Mo, W, Cu and Re by soils and organisms in the Baksan River basin owing to the anthropogenic contamination by the former Tyrnyauz W–Mo industrial complex and migration of the metals with natural waters are discovered during biogeochemical studies of W–Mo mining landscapes of the North Caucasus and background territories. The man-made transformed soils of the Baksan River