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One of the pivoting problems in the genesis of magmatic deposits is the role of silicate melt in the origin of sulfide ores. A way of solving this problem is to compare massifs with different mineralization, using contents of major and trace elements in the rocks. However, intrusions of the Norilsk intrusive complex are rarely compared with one another in terms of ore composition and volume in them. This paper is the first geochemical data, all of which were acquired with the application of modern analytical techniques, on the Chernogorsky intrusion in the Norilsk trough. The structure and composition of this intrusion are well comparable to the intrusions of the same complex hosting the uniquely large deposits: Talnakh, Kharaelakh, and Norilsk 1. The weighted mean composition of the Chernogorsky intrusion (wt %) is as follows: 47.2 SiO2, 0.62 TiO2, 16.7 Al2O3, 9.94 FeO, 0.16 MnO, 11.7 MgO, 11.3 CaO, 1.53 Na2O, 0.46 K2O, 0.07 P2O5, and 0.18 Cr2O3,, and the ratios of trace elements (La/Sm)n = 1–2, (Gd/Yb)n = 1.2–1.4, and (Th/Nb)n = 1–4 are same as typical of other rocks of the Norilsk complex. The ores of the Chernogorsky intrusion are close to the ores of Norilsk 1, their Cu/Ni ratio slightly exceeds 1, and the Pt + Pd = 5–6 ppm on average. However, the predicted resources of metals in this massif (0.8 Mt Cu + Ni and 0.5 kt Pt + Pd) are 140 times lower than the resources of the Kharaelakh intrusion (113 Mt Cu + Ni, 17.5 kt Pt + Pd), and 50 times lower than in Talnakh (40 Mt Cu + Ni, 8.3 kt Pt + Pd). This confirms that the ore content in an intrusion does not depend on the composition of its silicate rocks, and hence, the compositions of these rocks cannot be used as an exploration guide for new deposits.

—We present results of a study of plutonic-rock xenoliths from the Kharchinsky Volcano (Central Kamchatka depression). The studied xenolith collection comprises nine samples of peridotites and clinopyroxenites. The peridotites are identified as wehrlites, dunites, and harzburgites composed of olivine, clino- and orthopyroxenes, amphibole, and chromite in varying amounts. The clinopyroxenites consist mostly of clinopyroxene and often contain subordinate olivine, amphibole, hercynite, and magnetite. The xenoliths have interstitial segregations and veins composed of chlorite, plagioclase, K-feldspar, orthopyroxene, barite, fluorapatite, ilmenite, and, more seldom, anhydrite, phlogopite, and some other minerals. The study has revealed that veinlet minerals sometimes replace primary minerals and form pseudomorphs, thus indicating the metasomatic origin of interstitial and vein mineral assemblages. The thermobarometric calculations for minerals have shown that peridotites formed at ~1140 °C and ≤10 kbar in the intermediate chambers at the depths from the spinel stability field to the Moho. Interstitial metasomatic alterations of rocks took place at ~400–850 °C.

Interfacial separation of components of extractants based on di-(2-ethylhexyl)phosphoric acid (di-2EHPA) in toluene and a mixture of di-2EHPA with trioctylamine in toluene has been studied in the course of treatment with aqueous sodium hydroxide solutions yielding an organic phase and an aqueous colloidal solution of di-2EHPA sodium salt. Conditions have been found for the isolation of almost pure di-2EHPA and toluene, as well as di-2EHPA and a trioctylamine solution in toluene. The aqueous colloidal solutions have been studied by conductometry, dynamic light scattering, and 1H-NMR spectroscopy. The considered systems are promising to be used in hydrometallurgy for improving parameters of extraction of metals and their concentrating in re-extracts.

The extraction of cadmium from sulfuric acid solutions and its separation from nickel with salts of bis(2,4,4-trimethylpentyl)dithiophosphinic acid (Cyanex 301) and amines was studied. The data obtained show that extractants based on Cyanex 301 and Quaternary ammonium bases are most suitable for this since it is possible to extract cadmium in the form of sulfates and bisulfates as well as stripping metal from the organic phase. For deep extraction of cadmium from sulfate solutions in this system, 1–2 stages of extraction are sufficient. At this stage, the separation coefficient of cadmium and nickel βCd/Ni reaches values > 106, and the distribution coefficient of cadmium reaches almost 104. Cadmium stripping is achieved by treating the organic phase with an ammonia solution containing ammonia more than 4 mol/L. The process can be used in the processing of cadmium–nickel batteries.

The dunite–wehrlite–clinopyroxenite–gabbro massif in Eastern Chukotka, a key object for geodynamic reconstructions of the Vel’may terrane, which represents one of the segments of the southern border of the Chukotka folded system (Chukotka microcontinent, or Arctic Alaska–Chukotka microplate), is investigated. Mineralogical and petrological–geochemical studies of rocks of this massif are carried out. A comparative analysis of the primary mineralogy and formation conditions of cumulative rocks of dunite–wehrlite–pyroxenite–gabbro assemblages from modern island-arc systems, mantle transition zones, and crustal sections of ophiolites and ancient island arcs shows that the rocks studied are cumulates crystallized from a tholeiitic melt in an intraoceanic island arc at a moderately high pressure. The 40Ar/39Ar age of magnesian hornblende from gabbro indicates the massif was formed no later than in the Early–Middle Jurassic. The petrological and geochemical modeling suggests that the analyzed olivine clinopyroxenites and gabbros are probable plutonic comagmates of the Late Triassic island-arc basalts and dolerites of the Vel’may terrane. The arc segment represented by these rocks of the Vel’may terrane was probably part of the system of island arcs which had been reconstructed in this region for the age interval of 163 to 230 Ma. In addition, there is a tendency for the rejuvenation of the Middle Triassic–Late Jurassic island-arc magmatism in the direction from west to east, namely, from the South Anyui terrane of Western Chukotka through the Vel’may terrane of Eastern Chukotka to the Angayucham terrain of Alaska.

The extraction of iron(III) with tributyl phosphate from bromide aqueous solutions in the electrochemical processing of natural waters and brines was studied. It was found that iron(III) is extracted from solutions of alkali metal bromides in the form of the complex salt MFeBr4 at a salt concentration of more than 4 M. Extraction increases in the series KFeBr4 < NaFeBr4 < LiFeBr4. Extraction products are largely susceptible to electrolytic dissociation in the organic phase. The optimal conditions for the extraction of iron(III) bromide and its return to the technological process are determined.

Significant extraction degree of calcium and yttrium chlorides with solutions of the corresponding tetraphenylborates in tributyl phosphate has been revealed, due to the formation of mixed complex compounds in the organic phase. It has been shown that lithium, calcium, and yttrium tetraphenylborates are significantly dissociated in the organic phase. The process has been studied by conductometry. Based on the obtained data, it has been suggested that the formation of mixed halide complexes is owing to the high energy of the solvated ion pairs [CaLn]2+(A−)2 and [YLm]3+(A−)3 in organic solutions, which is significantly decreased upon the exchange of large tetraphenylborate anions with small chloride anions, possibly with the formation of solvated ion pairs with a lower charge of the cationic part of the complex [CaLn−1Cl]+A− or [YLm−2Cl2]+A−

Detailed mineralogical and melt and fluid inclusion constraints on magma storage, and the evolution of melts, are presented for the large-volume caldera eruption on the Vetrovoy Isthmus on Itutrup Island (Kuril Islands, Russia). The shallow magma reservoir beneath the Vetrovoy Isthmus is composed of a mush of plagio-rhyolitic melt, phenocrysts and the products of peritectic reaction(s). The melt appears to have formed as a result of partial melting of previously erupted rocks, which probably had andesitic to basaltic compositions and were metamorphosed into amphibole-bearing assemblages. The breakdown of amphibole in the partially melted precursor rocks led to the formation of early Mg-rich clino- and orthopyroxene, along with plagioclase and Fe–Ti oxides, and the release of aqueous fluids. Variations in fluid pressure are recorded by a strong increase of An contents in plagioclase. Crystallization took place at around 850°C with pressure ranging from 0·9 to 3 kbar. This study demonstrates that dacitic magmas erupted during the course of a 20 kyr voluminous eruption were the result of mixing between plagio-rhyolitic partial melts and the breakdown reaction minerals (i.e. pyroxenes, plagioclase and Fe–Ti oxides). Plagioclase and quartz were the last minerals to crystallize from these melts prior to eruption.

The paper presents study of the liquidus assemblage of olivine and spinel in high-magnesian basalts (MgO up to 10 mas. %) of the Menshiy Brat volcano (Iturup Island). It was possible to reconstruct the water content and evolution of volatile components in the primary parental magmas that took part in the formation of the Medvezhya Caldera, Iturup Islands. It is shown that the initial water content in the primary melts could reach 5 mas. % with oxygen fugacity corresponding to oxygen buffer NNO + 0.4 log. units. The evolution of magmas involved continuous degassing while magma rises to the surface. The water-rich fluid, which is constantly separated by evolving magma, could play a significant role in the formation of large siliceous magma chambers, which participated in catastrophic caldera eruptions.

Data from the study of minerals of the liquidus association (olivine and spinel) from high-Mg basalts (up to 10 wt % MgO) of Menshyi Brat Volcano (Iturup Island) are reported. Based on these data, it was possible to estimate the water content and to study the evolution of volatile components in the primary basic magmas that formed the Medvezhia Caldera (Irurup Island), for the first time. It is shown that the initial water content in melts could reach 5 wt % at an oxygen fugacity corresponding to the NNO + 0.4 buffer. The further evolution of magmas included continuous degassing at a depth of ≤8 km. Hydrous fluid separated from basic magma could play a significant role in the formation of large crustal chambers of siliceous magma participation in catastrophic caldera eruptions.

The complex niobium–rare earth pyrochlore–monazite–crandallite ores of the Tomtor deposit, located in the Siberian Arctic, should be considered as a new type of rare metal materials. The major valuable components of the ore are niobium (1.63–16.4%), rare earth elements (2.2–27.8%), yttrium (0.18–2.9%), and scandium (0.015–0.15%); associated components are titanium, vanadium, aluminum, and phosphorus. Because of the irregular distribution of the rare earth metals and niobium according to grain size, the extremely finely dispersed nature of the minerals and their close interpenetration to each other, ore processing by gravitation and flotation is not successful. The processes studied for the treatment of the Tomtor ores use direct alkaline-acid leaching to open the ore. A problem in the first stage of alkaline leaching is the high aluminum content, which decreases the activity of sodium hydroxide and alkaline-earth metals, which are bound to phosphorus. Ore processing using alkaline-nitrate and alkaline-chloride leaching was proposed and investigated. The first variant was used to obtain rare earth and scandium materials and a niobium–titanium concentrate, which can be a stock material for processors who use chlorination for the processing of ores and concentrates. The second variant is a complex advanced ore processing scheme with electrochemical regeneration of the waste chloride solutions obtaining sodium hydroxide, hydrochloric acid, and chloridizing agents. Moreover trisodium phosphate is used for purification of the waste mother liquors from metal cations. The complex salt, NaAlCl4, is proposed as the chloridizing agent for the decomposition of the niobium–titanium concentrate. The recovery of rare earth metals in the second variant of processing is about 95%; while for niobium and titanium, this value is 92–94%.

An augmented reality display based on a planar waveguide made in photo-thermo-refractive glass had been demonstrated. The monolithic integration of multiplexed volume Bragg gratings with the waveguide platform provided in/out-coupling and image transmission from a portable projector. Design and calculation of the grating configuration was performed. The optical replication method was simulated and implemented for manufacturing the multiplexed coupling elements. Resulted field of view was limited by the projection system of the prototype, however can be expanded beyond 50o.

Generalization of available literature and new original data showed that the Early Cretaceous high-Mg alkaline magmatism is confined to the ancient Lambert rift zone. Alkaline ultramafic rocks developed in the areas of this zone (Jetty Oasis, western flank of the Beaver and Radok lakes, Fisher and Meredith massifs) were derived through melting of metasomatized continental mantle at ~1270°С and at depths of 130–140 km. Variations of major and trace-element composition and the wide range in olivine composition (Fo91–Fo80) are consistent with its change through intrachamber crystallization. The average values of initial isotope composition of ultra-alkaline high-Mg basalts are as follows: 143Nd/144Nd—0.512485, 87Sr/86Sr—0.70637, 207Pb/204Pb—15.671, 206Pb/204Pb—18.391, 208Pb/204Pb—38.409. They are close to the model ЕМII source and can be arbitrarily taken as the preliminary assessment of isotope composition of a source of Mesozoic melts. Based on lithophile element and isotope compositions, the alkaline high-Mg basaltic magmatism is thought to be related to the thermal impact of the Kerguelen plume on the lithospheric mantle of East Gondwana 120–110 Ma. Similar ancient deep-seated metasomatized eastern Gondwanan mantle, which contains carbonates and biotite and has an age of 2.4 Ga, was found in southern East Antarctica as well as in the north within eastern India.

The objects of study are Triassic hypabyssal diamondiferous kimberlites with an age of 220–245 Ma, containing macrocrysts of unaltered olivine. The latter are close in the time of formation to the main stage of intrusion of the Siberian Trap Province (252 Ma), which lasted less than 1 Myr. A comparative high-precision analytical study of the Ti, Ca, Cr, and Al impurity patterns in about 1000 olivine macrocryst samples with a forsterite content Fo = (100Mg/(Mg + Fe)) of 78 to 93 has demonstrated the effect of traps on the lithospheric composition. A comprehensive comparative study of diamonds from northern placers and Triassic kimberlites, including determination of their carbon isotope composition, was performed. Chromatography–mass-spectroscopic analysis of submicron fluid inclusions in diamonds from northern placers and kimberlites has shown predominant hydrocarbons of a wide range of compositions and subordinate contents of N2, H2O, and CO2. These findings, together with the results of previous studies of subcalcic Cr-pyropes and diamonds found in the Lower Carboniferous gritstones of the Kyutyungde graben, lead to the conclusion that the Toluopka kimberlite field is promising for Paleozoic kimberlites. The results of comprehensive studies of diamonds and indicator minerals and U/Pb isotope dating of numerous detrital zircon samples from the basal horizon of the Carnian Stage (Upper Triassic) of the Bulkur site in the lower reaches of the Lena River suggest the presence of diamondiferous kimberlites within the northeastern Siberian Platform. The age of the probable primary diamond sources in the study area can be evaluated by an integrated U/Pb isotope dating of zircons, perovskites, and rutiles from the developed diamond placers and the basal horizon of the Carnian Stage.

The process of recovery by direct extraction of metal bromides from calcium chloride brines using mixtures of molecular iodine with tributyl phosphate has been studied. It was found that iodine significantly increases the recovery of the bromides of alkali and alkaline earth metals due to the formation of hydrophobic iodine complexes with the halide anions. Bromides of calcium and lithium are the most selectively extracted. The extracted complexes significantly dissociate into ions in the organic phase. The extraction of calcium halide over a wide range of its concentration in an aqueous solution results in the extraction of a mixed chloride-bromide salt. This is due to a significant difference in the separation factors for bromide and chloride ions in the interphase exchange reactions for the halide ions of the inner and outer coordination spheres of the extracted complex.

The Matachingai River basin is known among the few ophiolitic complexes on eastern Chukotka as the southern boundary of the Chukotka Fold System (in terms of tectonics, the Chukotka microcontinent or a fragment of the Arctic Alaska–Chukotka microplate). This complex comprises tectonic blocks of residual spinel harzburgite with dunite bodies and pyroxenite, olivine gabbro, and leucogabbro veins; blocks of hornblende gabbro, diorite, and plagiogranite; and Upper Jurassic–Lower Cretaceous basaltic–cherty and cherty–carbonate rocks. The geological relationships of rocks within tectonic blocks, the compositions of primary minerals, the bulk geochemistry of rocks, as well as the strontium, neodymium, and lead isotopic compositions, make it possible to consider individual tectonic blocks of the complex as fragments of a disintegrated oceanic-type lithosphere that formed in a back-arc spreading center. The melts, crystallization products of which are represented by hornblende gabbro of blocks, olivine gabbro of veins, and basalts, separated from geochemically and isotopically heterogeneous mantle. Blocks composed of rocks with various modal composition are likely relicts of an oceanic lithosphere of different segments of a back-arc basin. The studied complex may be a lithosphere of one of the Middle–Late Jurassic back-arc basins. Fragments of these basins are retained in ophiolitic complexes on Great Lyakhovsky Island of the New Siberian Islands Archipelago, western Chukotka, and the Brooks Range in Alaska.

We studied combined effect of β-hairpin antimicrobial peptide tachyplesin I and cytotoxic agent cisplatin on tumor and normal human cell lines. MTT assay and flow cytometry showed that tachyplesin I selectively sensitized cancer cells to cisplatin in specified concentration ratios. In vitro experiments demonstrated that combined use of tachyplesin I and cisplatin allows decreasing the effective dose of the cytostatic thus reducing nonspecific toxicity.

A periodic character of the evolution of trap magmatism was inferred by many researchers from the fact that sequences of volcanic rocks consist of alternating units of lava flows and tuff. A new phase of studying magmatic rocks in the Siberian Platform was related to the possibility of apply high-precision geochemical techniques in studying trace elements and Sr, Nd, and Pb isotopic compositions. The use of these techniques made it possible not only to identify small individual cycles in the vertical sections of volcanic rocks but also to distinguish larger stages. The currently most widely acknowledged scenario of the origin of volcanic rocks involves three stages, during which oceanic-island basalts (OIB), transitional series (intermediate between OIB and WPB), and within-plate basalts (WPB) were formed. This scenario was inferred mostly from data on rocks in the western part of the Norilsk area (Kharaelakh Trough). This publication presents recently obtained data on the inner structure of the sequences of volcanic rocks and the geochemistry of basalts in the eastern part of the territory, where no rocks show transitional characteristics have ever been found. They can be classified into two types that have clearly different composition and occur in different areas. These types characterize two major stages of the origin of volcanic rocks: rift-related and trap magmatism itself. The rocks produced during these stages occur at neighboring territories.

For the Permian–Triassic foidite and meimechite lavas of Polar Siberia, both the whole-rock petrochemistry and geochemistry and that of melt inclusions in olivine phenocrysts from the same rocks have been demonstrated to be similar. In addition, their isotope characteristics imply the possibility of their generation from an abyssal parental melt compositionally resembling a high–Mg alkaline picrite.

The probability of obtaining of ash-free coal extracts, so-called “hyper-coals,” has been shown for coals of the Pechora basin for the first time. The ash content in them does not exceed a few percent, whereas initial coals contain up to 20% ash. High-resolution 13C NMR shows the similarity in the structure of the initial coal and the extract. It is demonstrated that the solvent selected for hyper-coal extraction is not chemically inert, and the products of interaction of N-metylpyrrolidone and organic matter of coal are present in the composition of the extracts obtained.

The small volcanic islands of the central Greater Kuril Chain (GKC) produce strong explosive eruptions, two of which occurred in the recent years. The latest eruption took place at Raikoke volcano, which occurred on June 21–25 (2019) and was one of the largest on the Kuril Islands in the 21st century. This study presents mineralogical, petrographic and geochemical data on the air fall ash and pyroclastic density current deposits to elucidate the causes of high explosivity of this eruption. The magma involved in the Raikoke volcanic eruption is likely to have had a mantle origin and basaltic composition. Prior to forming a near-surface reservoir, the magma fractionated (i.e. due to crystallization of olivine and pyroxene) at depths of about 26 km, which is close to the Moho discontinuity in the middle part of GKC. The presence of amphibole among the 2019 pyroclastic minerals indicates that the magma contained significant (i.e. no less than 4 wt%) amounts of water at depth. This magma was degassed prior to intrusion into a shallower reservoir. The magma in the shallow reservoir had high crystallinity and contained viscous felsic residual melts, which prevented the development of effusive eruptions or Strombolian explosions. It is likely that magmatic fluid bubbles were still present, but their abundance was insufficient for lava fragmentation in the conduit. This led to low degree of vesiculation of the erupting melts. The results of this study demonstrate that the explosivity of the eruption is most likely related to the interaction in the volcanic edifice between meteoric waters and the magma, which was largely degassed and contained significant amounts of crystals and felsic melt (i.e. had high viscosity and low mobility).

Tholeiitic melts from the Bouvet triple junction (BTJ) of rift zones in the South Atlantic are moderately enriched rocks with specific lithophile-element patterns. The high (Gd/Yb)n values (up to 2.5) in some tholeiite compositions suggest the presence of garnet in the mantle source of primary BTJ melts. The high Ni and low Mn contents of the most magnesian olivines determined by high-precision probe microanalysis suggest the presence of pyroxenite, along with typical peridotite, in the melting source. The unusually wide within-sample variation in the proportions of pyroxenitic component in the source region (XPx Mn/Fe = 0–90%) indicates different degrees of mantle heterogeneity beneath the spreading zone. Based on geochemical data, this component is a silica-oversaturated eclogite, reacting with peridotite to form olivine-free pyroxenite in the melting source. This component is probably represented either by subducted and recycled oceanic crust or by fragments of the ancient continental lithosphere buried into the mantle after the Gondwana breakup. The observed global and local mantle heterogeneities might have been developed during the complex geodynamic evolution of the Southern Ocean, whose opening was affected by the activity of the Mesozoic Karoo–Maud–Ferrar plume and multiple jumps of the spreading axes, which led to the involvement of fragments of the early oceanic lithosphere in the melting process.

The Chuktukon niobium-rare earth elements ore deposit is located in Siberia (Russia). Weathered carbonatite crusts are the basis of the ore deposit. The deposit itself is 3.5 km in length, about 800 to 1400 m in width and up to 200–300 m in thickness. The ores are composed of iron-manganese oxides (hydrogoethite, hematite, psilomelane, pyrolusite) and contain 3–7 wt.% of rare-earth phosphates (florencite, monazite) and 0.5–1 wt.% of niobium oxide (pyrochlore). The ore is completely finely dispersed and consists of oxide particles formed of compact, dense aggregates which makes ore dressing as well as leaching of the rare and radioactive elements very difficult. Several options for processing of these ores have been considered: 1) reduction of the iron oxides to magnetite followed by beneficiation with magnetic separation to produce a rare metal concentrate; 2) processing of the rare earth elements (REE) containing minerals by direct alkaline-acid treatment; 3) processing of the ores using nitric acid leaching in an autoclave.

Cathodoluminescence (CL) microscopy studies were performed to unravel internal structures and zonations of carbonates from 6 unaltered hypabyssal kimberlites from several Mesozoic - Paleozoic kimberlite pipes of the Siberian craton. Different generations of prograde and retrograde carbonate grains/domains were identified. Most investigated kimberlite samples are unusually fresh and contain abundant unaltered olivine. Only minor amounts of carbonates of a primary magmatic origin were found; most carbonates are of secondary origin formed during late metasomatic or hydrothermal events. A rare carbonatite xenolith discovered in the Malokuonapskaya kimberlite contains abundant apatite and monazite; an apatite inclusion was detected in one zircon grain. Some apatites contain oriented lamellae of monazite. Early studies of the carbonate minerals in this xenolith demonstrated a trace amount of Sr; all these characteristics are typical of carbonatite. We conclude that carbonate minerals play a significant role in the evolution of hypabyssal kimberlites of the Siberian craton. The CL-studies of these minerals provide significant insights into their growth history and help to differentiate different parageneses, as either primary or secondary. Carbonatite xenoliths are of vital significance for the discussion of a possible genetic interrelation of kimberlite and carbonatite melts in the mantle. The present results may serve as a starting point for future studies of these carbonate minerals, using electron-microprobe, micro-PIXE or other high-resolution techniques. Future in-situ oxygen and carbon isotope analyses, as well as inclusions of melt, fluid, and minerals in different carbonate domains, will add essential new data with which to further unravel the genesis of the kimberlite-carbonatite association.

The primary melt and fluid inclusions in regenerated zonal crystals of olivine and homogeneous phenocrysts of olivine from kimberlites of the Udachnaya-East pipe, were first studied by means of microthermometry, optic and scanning electron microscopy, electron and ion microprobe analysis (SIMS), inductively coupled plasma mass-spectrometry (ICP MSC), and Raman spectroscopy. It was established that olivine crystals were regenerated from silicate–carbonate melts at a temperature of ~1100°C.

It has been demonstrated for the first time that the isotopic compositions of carbon (δ13C) in magmatic calcites from the Udachnaya–East pipe kimberlite groundmass varies from–2.5 to–1.0‰ (V-PDB), while those of oxygen (δ18O) range from 15.0 to 18.2‰ (V-SMOW). The obtained results imply that during the terminal late magmatic and postmagmatic stages of the kimberlite pipe formation, the carbonates in the kimberlite groundmass became successively heavier isotopically, which indicates the hybrid nature of the carbonate component of the kimberlite: it was formed with contributions from mantle and sedimentary marine sources.

Palynological (dinocysts) and geochemical data were compared for the first time for Paleogene sediments of borehole no. 8 (settlement of Russkaya Polyana, Omsk oblast). The layers with a concentrated amount of dinocysts of the genus Pseudokomewuia (20.5% of the palynocomplex) are characterized by higher contents of Fe, P, Ti, Nb, Ta, and W. The microphytoplankton bloom (an analog of the present-day red tides) in the late Oligocene Turtas Lake–Sea was probably caused by a greater contribution of nutrient substances from the continent during the transgression of this basin. Comparative analysis of the geochemical features of marine and continental Paleogene sediments from borehole no. 8 showed that the Turtas basin was either freshwater or had brackish water.

Comparative analysis of ultramafic meymechites of the Maimecha Suite and alkaline volcanics of the Ary-Dzhang Suite (foidites (nephelinites, analcimites, limburgites, etc.) and melilitites) has shown their consanguinity, which indicates their relationship with the same magmatic system periodically producing large amounts of alkaline ultramafic melts. We have studied the petrogeochemical and mineralogical compositions of rocks and melt inclusions in the hosted olivines. The rocks of the Maimecha and Ary-Dzhang Suite differ considerably in MgO content, which is well explained by the accumulation of olivine. The inclusions in olivines from the meymechites and the rocks of the Ary-Dzhang Suite correspond in composition to foidites. The trace and rare-earth element patterns are similar both in the foidites and meymechites and in the melt inclusions: They show negative anomalies of Rb and K and positive anomalies of Nb and Ta. The ratios of indicator elements (Nb/Ta, Ba/La, Ta/La, etc.) in the rocks of the Maimecha and Ary-Dzhang Suite are constant and almost independent of their Mg# values. The La/Yb ratio in the foidites is significantly higher than that in the meymechites and in the melt inclusions from their olivines, which indicates that the rocks of the Ary-Dzhang Suite resulted from the fractionation of highly magnesian alkaline picritoid melt.

Pyroxenite veins in mantle peridotites of the Unnavayam sheet of the Kuyul ophiolite terrane (Koryak—Kamchatka folded area) are composed of clinopyroxenite and websterite crystallized from a boninite-like melt. The host clinopyroxene-bearing spinel harzburgites are moderately depleted residues, whose mineral compositions and conditions of formation correspond to those of peridotites from mid-oceanic and back-arc spreading centers. Mantle peridotites of the Unnavayam sheet may have formed a part of the mantle wedge above a subduction zone and have been intruded by boninitic melts at a certain stage of their evolution.

Magmas forming large igneous provinces (LIP) on continents are generated by extensive melting in the deep crust and underlying mantle and associated with break-up of ancient supercontinents, followed by formation of a new basaltic crust in the mid-oceanic rifts. A lack of the unifying model in understanding the sources of LIP magmatism is justified by lithological and geochemical complexity of erupted magmas on local (e.g. a cross-section) and regional (a single and different LIP) scales. Moreover, the majority of LIP rocks do not fit general criteria for recognizing primary/primitive melts (i.e.

The paper reports the first results of the petrological studies of magmatic melts that formed siliceous pyroclastic deposits related to voluminous eruptions on Iturup Island. The caldera-forming eruptions of the Lvinaya Past and the Vetrovoy Isthmus, having similar features, resulted from the evolution of silicic melts that originated from partial melting of metabasalts. According to the mineral thermometry results, the melt was crystallized at ~800°C. The phenocrysts from the Vetrovoy Isthmus pumices were crystallized at

Mineralogical studies and U–Pb dating have been carried out on rutile included in peridotitic and eclogitic garnets from the Internatsionalnaya pipe, Mirny field, Siberian craton. We also describe a unique peridotitic paragenesis (rutile + forsterite + enstatite + Cr-diopside + Cr-pyrope) preserved in diamond from the Mir pipe, Mirny field. Compositions of rutile from the heavy mineral concentrates of the Internatsionalnaya pipe and rutile inclusions in crustal almandine-rich garnets from the Mayskaya pipe (Nakyn field), as well as from a range of different lithologies, are presented for comparison. Rutile from cratonic mantle peridotites shows characteristic enrichment in Cr, in contrast to lower-Cr rutile from crustal rocks and off-craton mantle. Rutile with Cr2O3 > 1.7 wt% is commonly derived from cratonic mantle, while rutiles with lower Cr2O3 may be both of cratonic and off-cratonic origin. New analytical developments and availability of standards have made rutile accessible to in situ U–Pb dating by laser ablation ICP-MS. A U–Pb age of 369 ± 10 Ma for 9 rutile grains in 6 garnets from the Internatsionalnaya pipe is consistent with the accepted eruption age of the pipe (360 Ma). The equilibrium temperatures of pyropes with rutile inclusions calculated using Ni-in-Gar thermometer range between ~ 725 and 1030 °C, corresponding to a depth range of ca ~ 100–165 km. At the time of entrainment in the kimberlite, garnets with Cr-rich rutile inclusions resided at temperatures well above the closure temperature for Pb in rutile, and thus U–Pb ages on mantle-derived rutile most likely record the emplacement age of the kimberlites. The synthesis of distinctive rutile compositions and U–Pb dating opens new perspectives for using rutile in diamond exploration in cratonic areas.

The composition of volatile components in picroilmenites from Yakutian kimberlitic pipes of various ages (the Olivinovaya, Malokuonapskaya, and Udachnaya–East pipes) was studied for the first time by means of gas chromatography–mass spectrometry (GC-MS). It was shown that picroilmenites and olivines from same kimberlitic pipes contained volatile components of close composition, whereas these components were quite different in these minerals from different pipes. These features point to a common source and represent the specificity of the magma chamber formed under the pronounced influence of hydrocarbons with their derivates, as well as nitrogen-, chlorine-, and sulfur-containing compounds. The fraction of hydrocarbons and derivates in the composition of volatile matter is as high as 99%, including 9.7% of chlorine- and fluorinecontaining compounds.

The composition of volatiles from fluid and melt inclusions in olivine phenocrysts from Yakutian kimberlite pipes of various ages (Olivinovaya, Malokuonapskaya, and Udachnaya-East) were studied for the first time by gas chromatography–mass spectrometry. It was shown that hydrocarbons and their derivatives, as well as nitrogen-, halogen-, and sulfur-bearing compounds, played a significant role in the mineral formation. The proportion of hydrocarbons and their derivatives in the composition of mantle fluids could reach 99%, including up to 4.9% of chlorineand fluorine-bearing compounds.

The results of study of crichtonite group minerals in pyropes from the Internatsionalnaya kimberlite pipe are reported. Most of the studied samples are characterized by high concentrations of Sr, Ca, Na, and LREEs in comparison with minerals of the LIMA series from kimberlites of South Africa, whereas the average concentrations of Ba and K are significantly lower. Crichtonite group minerals in pyropes are characterized by predomination of Na over K in most samples and by a high concentration of Al2O3 (up to 4.5 wt %). Findings of inclusions of crichtonite group minerals with high concentrations of incompatible elements provide evidence for the metasomatic origin of host chromium-rich pyropes.

The results of study of rutile inclusions in pyrope from the Internatsionalnaya kimberlite pipe are presented. Rutile is characterized by unusually high contents of impurities (up to 25 wt %). The presence of Cr2O3 (up to 9.75 wt %) and Nb2O5 (up to 15.57 wt %) are most typical. Rutile inclusions often occur in assemblage with Ti-rich oxides: picroilmenite and crichtonite group minerals. The Cr-pyropes with inclusions of rutile, picroilmenite, and crichtonite group minerals were formed in the lithospheric mantle beneath the Mirnyi field during their joint crystallization from melts enriched in Fe, Ti, and other incompatible elements as a result of metasomatic enrichment of the depleted lithospheric mantle.

In this paper it was carried out the numerical simulation of the main working parameters (light current- voltage curves, quantum yield spectral distributions) of SnS-based (SnS/SnS2/ITO, SnS/ZnS/ITO) solar cells (SCs) using the SCAPS-3102 simulation package. Using the basis input simulation parameters such as wide band gap Eg,, layers thicknesses d, electron affinities х, etc. there were estimated the next SCs characteristics: open-circuit voltages UOC, short-circuit current densities JSC, fill-factors FF and their efficiencies ᶯ . These data allows us to estimate the optimal constructive parameters of simulated SCs. В даній роботі проведене числове моделювання основних експлуатаційних характеристик (світлові вольт-амперні характеристики, спектральні розподіли квантової ефективності) сонячних елементів (СЕ), виконаних на базі шару SnS (SnS/SnS2/ITO, SnS/ZnS/ITO) з використанням програмного пакету SCAPS-3102. Обравши такі базові характеристики для моделювання, як ширина забороненої зони Eg,, товщини шарів d, спорідненості електронів х, тощо, були отримані наступні експлуатаційні характеристики СЕ: напруга холостого ходу UOC, густина струму короткого замикання JSC, фактор заповнення FF та коефіцієнт корисної дії фотоперетворення ᶯ. Отримані значення дозволили визначити оптимальні конструктивні параметри змодельованих сонячних елементів. В данной работе было проведено численное моделирование основных эксплуатационных характеристик (световые вольт-амперные характеристики, спектральное распределения квантовой эффективности) солнечных элементов (СЭ), исполненных на основе слоя SnS (SnS/SnS2/ITO, SnS/ZnS/ITO) с использованием программного пакета SCAPS-3102. Избрав такие характеристики для моделирования, как ширина запрещенной зоны Eg,, толщины слоев d, электронное сродство х, и т.д., были получены следующие эксплуатационные характеристики СЭ: напряжение холостого хода UOC, плотность тока короткого замыкания JSC, фактор заполнения FF и коэффициент полезного действия фотопреоб- разования ᶯ. Полученные значения позволили определить оптимальные конструктивные параметры смоделированных солнечных элементов.

The primary fluid and melt inclusions in regenerated zonal crystals of olivine from kimberlites of the Malokuonapskaya pipe were first examined by means of microthermometry, optic and scanning electron microscopy, and Raman spectroscopy. The high-pressure genesis of homogenous central parts of the olivines was revealed, probably under intense metasomatism at early hypogene stages with subsequent regeneration in the kimberlitic melt. The olivine crystals were regenerated from silicate–carbonate melts at about 1100°C. The composition of the kimberlitic melt was changed by way of an increase in the calcium content.

ISSN 1028334X, Doklady Earth Sciences , 2015, Vol. 463, Part 2, pp. 828–832. © Pleiades Publishing, Ltd., 2015.Original Russian Text © N.V. Sobolev, A.V. Sobolev, A.A. Tomilenko, V.G. Batanova, A.V. Tolstov, A.M. Logvinova, D.V. Kuz’min, 2015, published in Doklady Akademii Nauk,2015, Vol. 463, No. 5, pp. 587–591.

The paper deals with Russian geographical terms in the Karelian dialects of Tver Region and is mainly based on field materials collected by the author in the 2000s. The author argues that the main corpus of geographical terms and place names of the studied area is of Karelian origin and correlates with geographical terminology and toponymy of other groups of the Karelian population that migrated in the past from the north-eastern Lake Onega Region. At the same time, as distinct from other areas of settlement of the Karelian population, the dialects of Tver Karelians are rich in loan words from the Russian language which appeared in different periods: a part of them represent traditional geographical terms of the Russian population of Tver Region, while others seem to be relatively recent innovations, mainly of the Soviet period. According to the data provided by the author, approximately 40 % of current geographical terms of the Karelian dialects of Tver region are of Russian origin. This proportion can be explained by the specificity of the landscape of the studied territory which differs from the landscape of the original Karelian areas, as well as by Tver Karelians' long habitation in the Central Russian Historical Zone which made permanent contacts with the Russian population inevitable.

Unaltered Mg-olivine (Fo = 85-94) is a predominant mineral of the kimberlite block (serpentine-free) of the Udachnaya-East pipe, and it prevails in peridotite xenoliths and as inclusions in diamonds. The kimberlite of this pipe, like a series of hypabyssal kimberlites in other regions, contains two main types of olivine macrocrysts according to their size and morphology: those rounded or irregularly shaped (olivine I) and euhedral phenocrysts (olivine II), which are usually no larger than 0.5 mm and very seldom reach 1 mm in size. This study was focused on several thousand olivine samples assigned both to olivines I and to olivines II, with a gradual transition between them. Particular attention was paid to the search for mineral inclusions in olivine and for phenocrysts with a clear zoning. In the phenocryst cores of homogeneous composition, we have revealed orthopyroxene inclusions as well as clinopyroxene (chrome-diopside and chrome-omphacite) inclusions with wide variations in the Na2O and Cr2O3 contents, significantly higher than the previously established ones: up to 6.00 wt.% Na2O and 4.23 wt.% Cr2O3. Convincing evidence for the high-pressure origin of the olivine macrocryst cores is the presence of pyrope inclusions with 1.41-9.14 wt.% &2O3, 4.64-6.61 wt.% CaO, and Mg# = 75.6-83.7 in six samples, which testifies to the high-pressure lherzolite paragenesis of the phenocrysts cores. The cores of the studied olivine phenocrysts are identical in the contents of Ni, Co, Ca, Cr, and Mn to olivines from diamonds and peridotite xenoliths. However, they differ significantly in the steady elevated Ti content, equal to 100-300 ppm for the majority of the phenocrysts, including those containing pyroxene and pyrope inclusions.

Petrological-geochemical data were obtained on the lamproites of the Gaussberg Volcano located at the eastern Antarctic coast and compared with data on the magmatic rocks developed in the East Antarctica and Indian Ocean in relation with the Kerguelen plume. It was shown that the lamproites were derived from the ancient Gondwana lithosphere repeatedly modified at the early stages of its evolution, including significant enrichment in volatiles, lithophile elements, and radiogenic Sr and Pb isotopes. The Gaussberg Volcano located on the eastern Antarctic continental margin falls in the distribution field of the Kerguelen plume, which formed 130 Ma within the incipient Indian Ocean and is continuing to operate at present, forming volcanic rocks of Heard Island in the last ka. Manifestations of alkaline magmatism at the Antarctic margin around 56 ka (Mt. Gaussberg) indicate a sublithospheric spreading of mantle plume in the southwestern direction.