V.A. Vernikovsky1,2, V.S. Shatsky2,3 1Trofimuk Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia 2Novosibirsk State University, Novosibirsk, Russia 3V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Tectonics, deep geodynamics, mantle plume, metamorphism, magmatism, geomagnetic field, Tomtor deposit, Siberia, Arctic
This special issue of the journal, dedicated to the memory of Academician Nikolai Leontievich Dobretsov, features papers reflecting the development of his research and ideas in the fields of his scientific interests. The diversity of Dobretsov’s scientific interests determined the broad range of topics covered in the presented papers: tectonics, deep geodynamics, the interaction of plate tectonics and mantle plumes, metamorphism, including ultrahigh-pressure metamorphism in subduction zones, structural patterns of geomagnetic and gravitational fields and their relationship with plume magmatism, and unique mineral deposits.
V.V. Yarmolyuk1, A.M. Kozlovsky1, V.M. Savatenkov2 1Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences, Moscow, Russia 2Institute of Precambrian Geology and Geochronology, Russian Academy of Sciences, St. Petersburg, Russia
Keywords: Intraplate magmatism, mafic rocks, rare elements, Sr-Nd-Pb isotopic composition, mantle plumes, plume-lithosphere interaction, Central Asia
The late Mesozoic-Cenozoic intraplate volcanic province of Central Asia unites a number of spatially isolated volcanic regions. Based on the examples of the South-Khangai, West-Transbaikal, and East-Mongolian regions, we demonstrate that three periods of activity can be distinguished in the province’s geological history. The initial period (between ~145 and 100 Ma) was characterized by a regional extension and riftogenic magmatism. The middle period (between 100 and 30 Ma) was distinguished by a quasi-platform tectonic regime and an areal type of volcanism. The late period (the last 30 million years) is distinguished as a period of lava plateau volcanism. The magmatism of the province is determined primarily by mafic rocks with elevated alkalinity. During the riftogenic period, trachybasalts and trachybasaltic andesites were formed, the geochemical signature of which was high REE contents with depleted concentrations of Nb and Ta. During the period of areal volcanism, trachybasalts and alkaline basaltoids with OIB characteristics became predominant. This rock type remains dominant in the volcanic associations of the final period of the province’s formation. The trends in variations of trace elements and the isotopic composition of Sr, Nd, Pb in mafic rocks of different ages in the province were determined and the compositions of their magmatic sources were estimated. We show that at all stages of the province development, one of the magma sourcecomponents remained constant and was close to the asthenospheric mantle of the EMORB type. During the rift period, subduction-metasomatized mantle also participated in magmatism. During the period of areal volcanism, the metasomatized mantle was gradually removed from the composition of melt sources. Since that time, the magmatism of the province has been determined by the interaction of asthenospheric, plume (OIB-type) and depleted lithospheric mantles. The formation of the province is associated with the emergence of a hot mantle field at the base of the East Asian lithosphere. Its origin is consistent with the activation of deep geodynamic processes in the early late Mesozoic, primarily with the activity of the Pacific superplume.
S.D. Sokolov1, L.I. Lobkovsky2,3, V.A. Vernikovsky4,5, V.A. Poselov6, O.E. Smirnov6, M.I. Tuchkova1, E.V. Shipilov7, N.O. Sorokhtin2, A.A. Baranov3,8, A.M. Bobrov8, S.M. Zholondz6 1Geological Institute, Russian Academy of Sciences, Moscow, Russia 2Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow, Russia 3Institute of earthquake prediction theory and mathematical geophysics, Russian Academy of Sciences, Moscow, Russia 4Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia 5Novosibirsk State University, Novosibirsk, Russia 6VNIIOkeangeologia, St. Petersburg, Russia 7Polar Geophysical Institute, Murmansk, Russia 8Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, Moscow, Russia
Keywords: Tectonics, geodynamics, Mesozoic, Eastern Arctic, Amerasia Basin, Chukotka, Arctic Alaska, Central Arctic uplifts
We provide a brief description of the main structures in the Eastern Arctic, in the evolution of which two major stages have been distinguished and considered: the late Paleozoic-early Mesozoic and the Late Jurassic-Early Cretaceous. We have established the synchronicity of tectonic events on the Arctic margins of Northeast Asia and Arctic Alaska and within the structures of the Amerasia Basin, indicating the existence of a cause-and-effect relation between the compression (fold-and-thrust structures) and extension (rifting and spreading in the Canada Basin). We have proposed the tectonic models of the formation of fold-and-thrust structures in Chukotka and Arctic Alaska and have determined their similarities and differences. Paleotectonic reconstructions have been performed for 160 and 120 Ma. We present a critical review of the concepts about the formation of the structures in the Amerasia Basin and provide a subduction-convection geodynamic model according to the analysis of seismic tomography of the mantle and regional geology and tectonics data. This model was previously used to describe the Cretaceous and Cenozoic evolution of the Arctic lithosphere at a qualitative level. The model is based on the idea of the existence of a two-tier subduction system: a horizontally extended convection cell in the upper mantle, coupled with a conveyor mechanism of subduction of the Pacific lithosphere. As a result, there is a convergence of the “outer” Pacific subduction zone and the “inner” subduction zone located inside the South Anyui and Angayucham oceanic basins, which provides their closure and subsequent collision. Under the influence of the reverse upper mantle flow, scattered deformations of the Amerasia lithosphere occur, caused by viscous dragging with flows beneath the lithosphere, which is the reason for the diversity of the structures in the Amerasia Basin and the Canada Basin in particular. In addition, the developed geodynamic model is supplemented by a tectonic and magmatic mechanism of crustal subsidence and the formation of sedimentary basins.
V.A. Vernikovsky1,2, A.N. Semenov1,3, O.P. Polyansky1,3, A.E. Vernikovskaya1,2, N.Yu. Matushkin1,2 1Novosibirsk State University, Novosibirsk, Russia 2Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia 3V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Collision, granite, rheology, heat flow, 3D modeling, Arctic, Kara orogen, North Taimyr, Siberian craton
Using 3D numerical modeling, we consider the formation of the postcollisional granitoids of the Kara orogen in Northern Taimyr 280-250 Ma under conditions of elevated heat flow due to the orogen’s breakup, prior to the magmatic activity of the Siberian mantle plume. The initial geometry of the model area, the boundary conditions and physical properties of the crust and mantle were set to be close to the structure of the Earth crust in the junction zone of the Kara, Central Taimyr and Siberian blocks. The model shows widespread melting in the granite-gneiss-andesite-basalt layer of middle crust, and a 1-2 km thick melting zone forming at the base of the crust in the granulite layer with the possible participation a mantle component. The magma ascent rate and the formation of groups of adjacent granitoid plutons depend on the value of the elevated mantle heat flow and on the rheology of the melting protolith rocks. The model shows the conditions for intrusion of magma and formation of plutons 10-20 km in diameter at depths 5-8 km in unmetamorphosed rocks. 3D modeling shows the mechanism of periodic magma intrusion pulses at the postcollisional stage during 30-40 Myr. The proposed formation mechanism for the plutons allows to reproduce such shapes and emplacement periodicity that are comparable to their actual geological position and age of the postcollisional granitoids of the Kara orogen. We compare the results of modeling in 2D and 3D configuration with identical model parameters and physical properties of the rocks. We conclude that 3D modeling is a more realistic and accurate means of description of the respective magmatic processes compared to the 2D one.
A.N. Didenko1,2, M.Y. Nosyrev2, G.Z. Gilmanova2, M.D. Khutorskoy1 1Geological Institute of the Russian Academy of Sciences, Moscow, Russia 2Institute of Tectonics and Geophysics, Far Eastern Branch of the Russian Academy of Sciences, Khabarovsk, Russia
Keywords: Curie Point Depth, plate boundaries, thermal anomalies and tectonic structures, Amur Plate
Based on the results of spectral analysis of the anomalous magnetic field, the depths of the roof and the base of the magnetoactive layer of the Amur Plate and adjacent territories were calculated. The causes of variations in the depth of the magnetoactive layer base (CPD) from 14 to 38 km (average 24 km) were determined. Maximum CPD depths are observed within sedimentary basins (Erlian, Songliao, and Middle Amur) in the southwest and in the central part of the plate. The areas of minimum depths in the continental part are located in the northwest within the giant granitoid batholiths (Angara-Vitim, Khentei) and in the northeast within the Bureinsky province. The third area of minimum CPD values is located within the waters of the Sea of Japan. The relatively high elevation of the magnetoactive layer base in the waters of the Sea of Japan is associated with rifting processes in the back-arc basin, which began at the end of the Oligocene, and the generation of fluids and magma chambers above the Pacific slab that is sinking under the Amur Plate. Two high CPD areas standing in the continental part of the plate are associated with the presence of two thermal anomalies. The north-western one is explained by the presence of a thermal crustal anomaly due to the process of radioactive heat generation by granitoids of the giant Angara-Vitim, Khangai and Khentei batholiths. The Northeastern Bureinskaya area is explained by the presence of an anomalous temperature of the mantle here. A comparison of the newly constructed CPD map with the boundaries of the Amur Plate, previously determined mainly from seismic data, shows that the surface boundaries of the plate coincide mainly with the zones of the greatest CPD gradients. All of them are associated with areas of increased seismic energy generation, with the exception of one small area on the southern border of the Amur Plate at its junction with the Yangtze Plate. In our interpretation, plate boundaries are not just lines on the surface, they are fairly wide zones from tens to the first hundreds of kilometers that encircle the plate.
D.V. Metelkin1,2, E.V. Vinogradov1,2, A.A. Eliseev1,2, M.E. Luzan1,2, V.V. Abashev3 1Novosibirsk State University, Novosibirsk, Russia 2Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia 3Geological Institute of the Russian Academy of Sciences, Moscow, Russia
Keywords: Hotspots, mantle plumes, geodynamo, geomagnetic reversal frequency, paleointensity, geocentric axial dipole, equatorial dipole, anomalous geomagnetic field, global magnetic anomalies, absolute plate reconstructions
We present an analysis of modern paleomagnetic data from large igneous provinces and paleorift structures in Siberia and the High Arctic that are potentially related to mantle plumes. The interrelationship between plume magmatism, geomagnetic reversal frequency, and field intensity over the last 600 Myr exhibits a periodicity of 70-100 Myr. Periods of mantle plume activity were preceded by an increase in geomagnetic reversal frequency, accompanied by a decrease in geomagnetic field intensity. Our proposed hypothesis explains this effect by changes in the thermal convection in the Earth’s outer core while mantle plumes are regarded as regulators of the state of the hydromagnetic dynamo. “Overheating” of the core increased the turbulence of convective currents, and therefore, the amount of reversals. During reversals, the value of the main component of the geomagnetic field - the geocentric axial dipole - first fell to zero and returned to high values only after a full reversal of the poles. Reduction of relaxation time in periods of frequent reversals led to prolonged low values of the absolute intensity of the geomagnetic field. Mantle plumes forming during such periods could remove the excess heat and stabilize the state of the geodynamo, even almost completely stopping reversals. We link the Ediacaran (Vendian) and Devonian geomagnetic phenomena to periods of ultra-frequent reversals. During these extended periods of low value of the axial dipole, the configuration of the geomagnetic field was determined by low-order non-zonal harmonics and by the global magnetic anomalies. We observe a qualitative coincidence of the position of paleopoles with centers of lower mantle gravitational and magnetic anomalies and postulate that the anomalies were stationary. This is the basis for substantiating a new reference framework for paleotectonic reconstructions in absolute coordinates. Examples of reconstructions made using this system also agree with the hypothesis of stationary hotspots. From the terminal Precambrian to the Mesozoic inclusively, the Siberian paleocontinent was located in the area of effect of the African mantle hot field, migrating northwards along the 0° meridian from the latitude of Tristan da Cunha to that of Iceland.
V.S. Shatsky1,2,3, A.L. Ragozin1, V.N. Reutsky1, V.V. Kalinina1 1V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia 2Novosibirsk State University, Novosibirsk, Russia 3A.P. Vinogradov Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russia
Keywords: Diamond inclusion, diamond formation, subduction zone
New evidence for the involvement of Fe-C-O melts in diamond formation from placers of the northeastern Siberian craton - combined with our data on iron carbide inclusions and previous research - provides a fresh perspective on diamond formation in subduction zones. Inclusions of iron carbides and oxides, along with moissanite and carbonates in polyphase inclusions, attest to a heterogeneous diamond-forming environment. Extreme variations in oxygen fugacity during diamond growth likely result from hydrogen and hydrocarbon generation via interaction between carbonated rocks of the subducting oceanic lithospheric slab and aqueous fluids. Separated hydrocarbon fluids can create localized ultra-reduced mantle regions where silicon carbide forms under conditions of nonequilibrium with the environment. A key characteristic of the studied diamonds is brittle fracture followed by crack healing, which is associated with the formation of polyphase iron carbide and oxide inclusions interpreted as trapped melts. We attribute brittle diamond fracture in the lower lithosphere to high strain rates localized in hypocenters of deep-focus earthquakes within the subducting lithospheric slab, triggered by dehydration or carbonatite melt formation.
E.V. Sklyarov1, A.V. Lavrenchuk2,3, E.V. Pushkarev4, Yu.D. Shcherbakov5 1Institute of the Earth’s Crust, Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russia 2V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia 3Novosibirsk State University, Novosibirsk, Russia 4Zavaritsky Institute of Geology and Geochemistry, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia 5A.P. Vinogradov Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russia
Keywords: Dunite, harzburgite, aluminous ultramafic rock, clinopyroxene-anorthite rock, sapphirine, corundum, Olkhon terrane, Western Cisbaikalia
Small bodies of restitic ultramafic rocks composed of dunite and harzburgite and enclosed in gneisses of the Olkhon composite terrane (West Baikal Area) are described. The estimates of the P - T conditions of metamorphism of the ultramafic rocks generally correspond to the metamorphic parameters of the host gneiss and amphibolite. The restitic rocks include unique aluminous ultramafic rocks composed of forsterite, enstatite, and chromium-free spinel. The latter are distinguished from restitic rocks by high contents of Al2O3 (up to 23 wt.%) at “peridotite” concentrations of magnesium (25-37 wt.% MgO) and silicon (30-42 wt.% SiO2). It is assumed that these rocks are the products of high-temperature (Max T = 730-790 °C) metasomatism of dunite and harzburgite. As shown by comparing the compositions of restitic and aluminous ultramafic rocks, the metasomatic process involves many elements, including those considered to be weakly mobile. The input elements are Al, Ti, V, Zr, and rare earth elements; the output elements are Mg, Si, Cr, and Ni. At the same time, there are no possible magmatic sources of metasomatizing fluids. It is assumed that host felsic gneiss served as a source of fluid at high-temperature metamorphism. The impact of metasomatizing fluids on aluminosilicate rocks, occurring as small fragments in restitic ultramafic rocks, strongly enriched them with alumina (up to 50 wt.% Al2O3) and formed specific mineral associations with corundum and sapphirine.
A.A. Tsygankov, G.N. Burmakina
Dobretsov Geological Institute, Siberian Branch of the Russian Academy of Sciences, Ulan-Ude, Russia
Keywords: U-Pb isotopic age, Lu-Hf, magma sources, geodynamics, Angara-Vitim batholith, western Transbaikalia
The late Paleozoic granitoid province of Transbaikalia (Angara-Vitim batholith (AVB), Russia), located in the northeast of the Central Asian Orogenic Belt (CAOB), occupies an area of about 200,000 km2. It is composed of rocks varying in composition from monzonites and quartz syenites to leucocratic granites. This research work is aimed at: 1) determination of the total duration and dynamics of formation of the Angara-Vitim batholith granitoids; 2) clarification of the reasons that determined the spatiotemporal heterogeneity of granitoids; 3) reconstruction of the sources of salic (granitoid) magmas and assessment of the contribution of mantle-crust interaction to the petrogenesis of granitoids. The paper is based on new petrogeochemical, isotope (Lu-Hf), and isotope-geochronological (U-Pb) data on the northern part of the AVB. Combined with the results of previous studies, it has been established that the AVB, one of the Earth’s largest granitoid provinces, formed over about 45 million years (from 320 to 275 Ma). During this time, about 90% of the batholith rocks formed. Crustal metagraywacke protoliths were the main source of salic magmas. The formation of monzonitoids, quartz syenites, and granodiorites is associated with the melting of mixed protoliths, in which the proportion of juvenile mafic material could reach 40-50%. The late Paleozoic granitoid magmatism in Transbaikalia began with the areal intrusion of calc-alkaline granites, granodiorites, and quartz syenites, which were predominant at the first stage of magmatism. At the second stage, magmatism took place in a narrow (200-250 km) permeable zone of NE strike. This zone drained crustal chambers of salic magmas and favored the penetration of mafic mantle melts into the upper crustal horizons. The AVB granitoids formed at the postcollisional stage of evolution of the eastern segment of the CAOB under the impact of mantle plume on the crust of the young orogen.
S.M. Zhmodik, E.V. Lazareva, V.A. Ponomarchuk, A.V. Tolstov, E.V. Airiyants, V.V. Sharygin, B.Yu. Saryg-ool, D.K. Belyanin, K.A. Musiyachenko, N.S. Karmanov
V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Carbonatite breccias, carbonates, pyrochlore, F-REE carbonates, C and O isotopes, Tomtor Complex of alkaline rocks and carbonatites
Carbonatite breccias were discovered by borehole G2 in the north of the Burannyi site in the Tomtor massif (complex) (TC) hosting the largest Sc-Y-Nb-REE ore deposit. The breccias are petrographically composite rocks consisting of fragments of dolomite, dolomite-ankerite, ankerite, and calcite carbonatites with significant amounts of F-REE carbonates, pyrite, and fluorite. They show signs of fragmentation of carbonatites and calcite rocks, transition of these fragments by younger melt-brine enriched in CO2, F, S, and REE, and its interaction with breccia fragments. The studied rocks are classified as magmatic-fluidogenic and fluidogenic breccias, which are a unique source of information about the rock composition and deep-level processes within the TC. The trace element spidergrams of the carbonatite breccias are similar to those of carbonatites and unique high-grade Sc-Y-Nb-REE ores of the upper ore horizon of the TC. The spidergrams show enrichment in Th, Nb, La, Ce, and Nd and depletion in U, K, Sr, Zr, Hf, and Ti, as in other carbonatite complexes of the world (including those with breccias). The REE pattern shows enrichment in MREE and HREE. The formation of carbonatite breccias is accompanied by the crystallization of unique REE minerals: synchysite-(Ce), parisite-(Ce), and/or bastnaesite-(Ce), cebaite-(Ce), and burbankite. Сrystallization of REE-fluorocarbonates is associated with dolomite replacement by ankerite. The maximum amount of these minerals, as well as cebaite-(Ce) and burbankite, is found in calcite rocks in association with fluorite and pyrite. It is shown that the δ18O and δ13C (‰) composition points in carbonatite breccia fragments and in the interfragmentary space form a trend with high correlation, which is similar to the trend of mixing of C and O isotopes of carbonatites and sedimentary carbonates. However, it contradicts the data on the increasing contents of REE, Nb, P, and other elements typomorphic for carbonatites with increasing δ18O and δ13C (‰) values and is the result of the transformation of carbonates by a low-temperature deuteric fluid. The first obtained comprehensive data on carbonatite breccias give grounds to consider them a new type of mineralization in the TC.
A.Sh. Shavekina1, V.A. Danilovsky1, O.L. Gaskova1, Yu.A. Kalinin1, R.V. Kuzhuget2 1 V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences,Novosibirsk, Russia 2 Tuvinian Institute for Exploration of Natural Resources, Siberian Branch of the Russian Academy of Sciences, Kyzyl, Russia
Keywords: Ag, silver, oxidation zone, halides, chalcogenides, supergene processes, Kyzyk-Chadr deposit, thermodynamic modeling.
The behavior of silver (Ag) in the oxidation zone of the Kyzyk-Chadr gold-sulfide-quartz deposit (Tuva Republic, Russia) has been studied. The main focus was on the mechanisms of Ag differentiation under supergene conditions, including the formation of its secondary minerals and its incorporation as an isomorphic impurity into other phases. It was found that Ag in the oxidation zone forms chalcogenides (acanthite, petrovskaite, uytenbogaardtite, jalpaite) and halides (iodargyrite, bromargyrite, mayersite), which are associated with malachite, chrysocolla, brochantite, quartz, and iron hydroxides. Electron probe microanalysis (EPMA) revealed that Ag concentrates in secondary copper sulfides (covellite, chalcocite, yarrowite, etc.), with levels as high as 0.7 wt.%. Optimization of EPMA parameters to improve resolution lowered the detection limit, enabling the determination of low Ag contents in chalcopyrite (up to 0.05 wt.%) and bornite (up to 0.09 wt.%). The sources of Ag are primary Ag tellurides and selenides, as well as primary and secondary Cu sulfides that break down during oxidation. Thermodynamic modeling simulated the behavior of Fe, Cu, and Ag during progressive oxidation of the primary assemblages (bornite, chalcopyrite, acanthite). The Eh-pH conditions controlling mineral migration and reprecipitation were calculated, and the element concentrations necessary for the formation of secondary phases were estimated.
The paper reviews the results of comprehensive studies and dating of contourite deposits from the Southwest Atlantic. It focuses on sediment transport and depositional processes as well as sediment sources in the context of Pliocene-Quaternary environmental and climatic changes. The work primarily highlights investigations conducted over the past decade by the Laboratory of Paleoceanology of the Shirshov Institute of Oceanology RAS in collaboration with other research groups over the last decade. The study examines contourite systems along the Argentine Patagonian continental slope, on the Santa Catarina and São Paulo plateaus, the Ioffe contourite Drift and the gravitite-contourite system, at the foot of the São Tomé Seamount . These systems were identified using a comprehensive approach combining seismo-acoustic, lithological, geochemical, and magnetic susceptibility data. Specific features of contourites that distinguish them from other types of deep-sea sediments are considered. The sediment age was defined by biostratigraphy and/or oxygen isotope stratigraphy and confirmed by AMS-14C dates (within the last 50 ka). The depositional system formation was predominantly controlled by erosion-depositional activity of bottom along-slope currents of the Antarctic origin. These Antarctic waters are a key component of Atlantic meridional circulation and the global conveyor system. Consequently, the contourite systems formed under the influence of these waters preserve a geological archive of the region's climatic and oceanographic history. The Ioffe Drift contains the longest sedimentary record in the study area, spanning the last 3.2 Ma. This time interval captures the development of modern-type paleoceanographic variability following the closure of the Panama Gateway. Other studied systems preserve sedimentary sequences documenting glacial-interglacial stages and associated changes in sea level, climate, and bottom current circulation during the Late Quaternary.
Merkulov O.I., Afanasenko A.P., Moskovsky I.G., Glukhova E.V. 1. JSC «Rosgeology», Moscow, Russia
2. JSC «Nizhne-Volzhsky Scientific Research Institute of Geology and Geophysics», Saratov, Russia
Keywords: hydrocarbons, hydrocarbon system modeling, geochemistry, hydrocarbon generation, compositional kinetic spectra, oil and gas source rocks, hydrocarbon potential, chromatography, pyrolysis
This article presents the fundamental principles of the author's technology for the justification and reconstruction of compositional kinetic spectra GeoArrhenius/SpectrOptim. The advantage of this technology lies in its ability to confidently separate gaseous hydrocarbons on the chromatogram and reconstruct multi-component (with an arbitrary number of components) kinetic spectra at the onset of catagenesis based on neural network modeling. Utilizing this technology in modeling hydrocarbon systems allows for accurate assessments of the volumes of hydrocarbons generated by the oil and gas source rock, and consequently, enables the evaluation of hydrocarbon resources in the area of study. This approach reduces the reliance on external and internal analogs during calculations, as well as the expert opinions of geological researchers.
U.A. Moroz1, A.V. Nikiforov1, V.V. Yarmolyuk1,2, A.M. Kozlovsky1, A.A. Ivanova3, E.V. Salnikova3, V.M. Savatenkov3, U.V. Plotkina3, А.К. Khertek2, N.A. Polyakov1 1 Institute of Geology and Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences, Russia 2 Tuvinian Institute for Exploration of Natural Resources of Siberian Branch of the Russian Academy of Sciences, Kyzyl, Russia 3 Institute of Precambrian Geology and Geochronology, Russian Academy of Sciences, St. Petersburg, Russia
Keywords: nepheline syenites, Central Asian Orogenic Belt, magma differentiation, isotopic composition, geochronology, Sangilen, rare-metal magmatism.
Massifs of alkaline granitoids and nepheline syenites are quite widespread in the territory of Eastern Tuva. Rare metal deposits and ore occurrences, which were formed mainly at the end of the Carboniferous period and in the Permian, are often associated with them. The Naryn massif includes nepheline syenites of the main phase, contact zone and a complex of 3 types of foidite microsyenite dikes. The age of the massif determined by zircon from the rocks of the main phase (SIMS – 315±3 million years) and dikes of microsyenites-1 (CA ID TIMS – 318±1 million years) showed an earlier time of its formation in the middle of the Carboniferous. Mineralogical, geochemical and Nd-isotope characteristics of the massif rocks suggest that the diversity of its rocks is associated with the same type of differentiation of a single initial magma, but occurring at different hypsometric levels. Crystallization of biotite-pyroxene-amphibole nepheline syenites of the main phase and feldspar liebnerite syenites of the marginal zone occurred at the upper level. From the lower chamber with the differentiating melt, dykes of apo-amphibole nepheline microsyenites-1, pyroxene-biotite microsyenites-2 and biotite nepheline microsyenites-3 were successively intruded. The evolution of melts, both at the upper and lower levels, occurred due to the precipitation of mafic minerals (amphibole), apatite and feldspar. With an increase in the alkalinity of the melts, accumulation of rare elements (Zr, Nb, Ta, REE) occurred, which are included in their own minerals at the late stages of rock crystallization. These data indicate that the foidite series rocks, widespread in Eastern Tuva, may be potentially ore-bearing, and the middle of the Carboniferous period should be considered as a phase of alkaline magmatism of the East Sayan rare-metal metallogenic zone. The Nd isotopic composition of the Naryn massif rocks (Nd(T) +6.3 – +7.1) does not suggest significant participation of the continental crust in the source of melts, therefore, sublithospheric alkaline-basaltoid magmas probably served as parental rocks for all the Naryn massif rocks.
Using a model sample of pyrite ore collected at the Degdekan gold deposit (North East Russia), we demonstrate the use of different variants of the IСP-MS method to determine the ratio of surficial-bound and structural-bound forms of trace elements (TE) in pyrite. Despite the difference in the physicochemical nature of the analysis methods involving the decomposition of crystals of different sizes (analytical data selections for single crystals - ADSSC) and direct determination by scanning the surface with a laser beam of different power (LA-IСP-MS), it has been shown that a number of elements tend to enrich the surface layer of pyrite crystals. The ratio of TE contents in the surface layer and in the volume (structure) of the crystal is defined as the selectivity (S) of surficial phases in the uptake of a given element. According to ICP MS – ADSSC data, the selectivity was 3.9 (Mn), 3.3 (Ag), 6.4 (Pd), 6.4 (La), 0.3 (Pr), 0.8 (Tb), 2.6 (Ho), 0.5 (Er), 1.0 (Lu), according to the results of LA-ICP-MS 3.9 (Mn), 1.4 (Co), 6.2 (Ni), 1.6 (Cu), 0.9 (Sb), 0.2 (Au), 0.3 (As), 6.8 (Ag), 18 (La), 46 (Ce), 5.2 (Pr), 11 (Nd), 1 (Eu), 0.6 (Dy). A comparison with experimental data for S Mn, Pd, and Ag reveals comparable results. However, it is concluded that LA-IСP-MS should be more representative in order to enable criterion-based statistical sampling (CBSS) according to a principle similar to ADSSC for more accurate discrimination of the structural component of TE concentration. Otherwise, significant errors are possible due to the influence of microinclusions of autonomous phases, in this case galena, which concentrates As, Au and Sb due to heterovalent isomorphism, resulting in S<1 for these elements. Most of the studied TEs show a direct correlation between selectivity and the difference in the ionic radii of the element and Fe, which confirms the relationship between S and the level of incompatibility of the impurity element in FeS2. High correlation coefficients between light REEs in the surface and the absence or negative correlations between light and heavy REEs are noted. This may reflect differences in the species of heavy and light lanthanides and requires more detailed study using LA-ICP-MS surface analysis and the application of the CBSS procedure. Despite the preliminary nature of the results, they deserve attention in practical terms as a justification for the development of technology for the extraction of critically important REEs as by-products in the processing and enrichment of pyrite ores and concentrates. They also justify the importance of the surface accumulation effect of REEs and the need to take it into account in meta-analysis and statistical processing of the results of analytical determinations of element content.
This paper describes a system for monitoring seismicity in specific volcanic areas of Kamchatka (Russia, Kamchatka Peninsula) based on estimates of the seismicity level according to the SESL’09 (Statistical Estimation of Seismicity Level) methodology. The application of the SESL’09 method to studying the preparation of volcanic activations is a promising approach for monitoring volcano state. We present the results of identifying seismically active source volumes for 10 active Kamchatka volcanoes. Nomograms were constructed for these volumes, allowing for the estimation of the seismicity level for any given time interval based on the seismic energy released within it. Examples of variations in the seismicity level of the volcanic areas, which are associated with the preparation for an eruption, are provided and support this conclusion.
A.V. Degterev¹, S.Z. Smirnov², D.V. Kuzmin², T.Yu. Timina², A.Ya. Shevko², I.R. Nizametdinov², F.A. Romanyuk¹, M.V. Chibisova¹ 1Institute of Marine Geology and Geophysics, Far Eastern Branch of the Russian Academy of Sciences, Yuzhno-Sakhalinsk, Russia
2V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Kuril Islands, Iturup Island, caldera, Lvinaya Past, pyroclastic deposits, explosive eruptions, pyroclastic flows, tephra, radiocarbon dating, geochemistry
At the end of the Pleistocene, two large-scale volcanic eruptions, associated with the formation of the Lvinaya Past caldera, occurred in the southern part of Iturup Island (Southern Kurils). These eruptions resulted in the formation of the largest partially submerged caldera in the Kuril Island arc, measuring 7×9 km, with a rim area of ~50 km² and a volume of ~25 km³ (including a submarine part of 12.26 km³). Comprehensive geological and geochronological studies established that the caldera formation was associated with two successive, very powerful explosive eruptions (LP-I and LP-II), separated by a repose period of several hundred years. The age of the first eruption (LP-I) is likely about 13,500 cal yr BP. The age of the second eruption (LP-II), determined from a series of radiocarbon dates, is estimated at ~12,300 cal yr BP. The eruptions were of Plinian type and involved the massive ejection of silicic pyroclastic material, represented by pyroclastic flow deposits and tephra. Based on silica and total alkali contents, the pumice from the caldera-forming eruption corresponds to low-alkali dacites and rhyodacites (SiO₂ 63.4–69.95 wt.%, total alkalis 3.9–5.5 wt.%), with less frequent andesitic (SiO₂ 58.3 wt.%, total alkalis 3 wt.%) and rhyolitic compositions (SiO₂ ~74 wt.%, total alkalis 5.6 wt.%). The total volume of erupted material from both events is preliminarily estimated at 80–100 km³ (DRE 35–45 km³), with the LP-II eruption being 30–40% more powerful than LP-I. It is suggested that the LP-I and LP-II eruptions, occurring only a few hundred years apart, could have impacted the natural environment on a regional and possibly global scale.
When conducting seismic surveys on the ground, it is usually not possible to place receivers with a uniform sufficiently frequent step over the area of observation. Interpolation (regularization) is an effective tool for generating additional seismic records without changing the spectral composition of data over time and with expansion of the spectral composition over space. This paper considers the optimization of a regularization algorithm based on iterative application of discrete Fourier transform (DPF) over a space known as ALFT (Anti-leakage Fourier transform). The proposed modification of ALFT is a way to reduce the set of test wave numbers when performing DPF. The effectiveness of the proposed algorithm was confirmed by processing both synthetic and field data. The calculation time has been reduced by several times compared to the original algorithm, and the results of recovery of skipped routes have not deteriorated. The results are valuable from a practical point of view and can be applied in future to the processing of ground-based seismic data on an industrial scale.
N.A. Mukhortina, E. V. Zippa 1Tomsk Branch of Trofimuk Institute of Petroleum Geology and Geophysics of Siberian Branch Russian Academy of Sciences, Tomsk, Russia
Keywords: polycyclic aromatic hydrocarbons, thermal waters, genesis of PAHs, technogenic load, water-rock system
New data on the composition and distribution of polycyclic aromatic hydrocarbons (PAHС) in thermal waters and host rocks in Baikal Rift Zone were obtained. It was shown that the total content of all identified individual compounds is 0.17-1.15 μg/L in the thermal springs and is 0.021-1.19 μg/kg in the rock. Naphthalene, phenanthrene, and dibenzo[a,h]anthracene dominate in the water. Phenanthrene, fluoranthene, and dibenzo[a,h]anthracene are predominant in the rock. The total PAHC content increased with TDS of water and with N2 and He growth in escaped gases. The calculated coefficients of technogenic load showed a low level of pollution for all studied sources. According to indicator ratios, the PAHC origin was determined. On the one hand, PAHC in thermal waters had petrogenic origin and were formed due to geochemical transformations of organic matter under high temperatures and pressures and microbial activity, entered with aqueous and gas along faults and fractures. On the other hand, some compounds have a natural pyrogenic origin, where pyrolysis products enter springs either at near-surface conditions or when mixing. The results let to characterize the composition of thermal waters in more detail and to describe a conceptual model the thermal waters composition formation in the studied region.
A. V. Drakon, A. V. Eremin, R. N. Kolotushkin, E. Yu. Mikheeva, E. S. Khodyko
Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow, Russia
Keywords: soot formation, soot particles, flat flame, LII, ethylene combustion, DME
The article presents experimental and calculated results of a study of the formation and growth of soot particles in a standard ethylene/air flat flame with dimethyl ether (DME) additive. Two-dimensional laser-induced incandescence (2D-LII) was used as an experimental method, obtaining data on the volume fraction of soot particles in the flame. The time-resolved LII signal provided information on the average soot particle size depending on the flame height. Kinetic modeling was performed using a modern kinetic mechanism of hydrocarbon pyrolysis and oxidation, including a sectional model of soot particle growth. It was shown that DME additives lead to a decrease in soot yield without significantly affecting the final particle size. Furthermore, DME additives slow down the initial stages of soot particle formation but accelerate their subsequent growth.
E. M. Makaryan, S. D. Arsentyev, M. Dzh. Pogosyan
Nalbandyan Institute of Chemical Physics, National Academy of Sciences of Armenia, Yerevan, Armenia
Keywords: chain reactions, methane oxidation, peroxide radicals
The mechanism of chain development during thermal gas-phase oxidation of methane was studied experimentally and theoretically. It was found that the rate-limiting step, which determines the overall process development, depends on the conditions. At a temperature of 728 K, the process is determined by the interaction of peroxide radicals with each other. Increasing the temperature to 873 K leads to an increased role for the reactions of peroxide radicals with formaldehyde, after which the rate-limiting step becomes the interaction of peroxide radicals with methane. Furthermore, changes in pressure and temperature have an equal effect on the concentration ratio of hydroperoxide and methylperoxide radicals, determined both by calculation and experiment.
A. M. Savelyev, V. A. Savelyeva, A. N. Tarasenko, S. A. Torokhov, I. N. Kadochnikov, D. V. Novakovsky
Baranov Central Institute of Aviation Motors, Moscow, Russia
Keywords: low-emission combustion, combustion chamber, modeling, surrogates
A skeletal reaction mechanism for the ignition and combustion of complex dodecane/decane/isooctane/isocetane/toluene surrogates of kerosene-type aviation fuels has been developed. The mechanism includes submechanisms for the oxidation of dodecane, decane, isooctane, isocetane, and toluene in the high- and low-temperature regions, as well as in the inverse temperature coefficient zone. The mechanism was tested using experimental data on ignition delay time, normal flame propagation velocity, and component concentration distribution. The combustion characteristics of the surrogates were tested using the developed reaction mechanism, and a demonstration CFD simulation of the operating process in a low-emission combustor of a gas turbine engine using rich-lean combustion technology was conducted.
G. V. Kuznetsov1,2, V. V. Dorokhov1,2, K. Yu. Vershinina1, P. A. Strizhak1,2 1Tomsk Polytechnic University, Tomsk, Russia 2Kutateladze Institute of Thermal Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: coal waste, composite fuels, combustion, gas emissions, nitrogen oxide emission reduction, multicriteria analysis
The results of an experimental study of the thermal oxidation characteristics and combustion product composition of coal slurry and composite fuels based on it, with the addition of water and dispersed wood, are presented. The positive effect of the additives on the critical ignition temperature, burnout efficiency, and anthropogenic gas emissions is substantiated. The main mechanisms and schemes for the formation and suppression of nitrogen oxides at different stages of thermal conversion are presented. The most effective conditions for reducing nitrogen oxide emissions are determined. Using a multicriteria analysis technique, the environmental, economic, and energy advantages of composite fuels over the original coal slurry are demonstrated. Dry fuel mixtures based on coal slurry and biomass with a mass fraction of the latter of 30 and 50% are found to have the greatest potential. Compared to coal slurry, the efficiency of such fuels is 30 to 45% higher. With maximum emphasis on environmental indicators, composite liquid fuels hold the greatest promise.
F. A. Bykovsky, S. A. Zhdan, E. F. Vedernikov
Lavrentyev Institute of Hydrodynamics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: continuous spin detonation, pulsating detonation, vortex radial combustion chamber, aviation kerosene, air, flow structure, specific impulse
Detonation combustion modes of a two-phase mixture of TS-1 aviation kerosene and air in a 500 mm diameter radial vortex chamber with a center-facing outlet, a nozzle, and axial baffles equalizing the product flow in the axial direction were implemented and studied. Continuous spin and pulsating detonation modes were achieved with strong (detonation wave) and weak (with combustion transition to detonation) initiation. It was found that with weak initiation, continuous spin detonation with a single transverse detonation wave was always achieved upon reaching the maximum specific impulse in this experimental setup - Isp,ƒ,max ≈ 1 600 s. A comparison was made between the specific impulses of this radial combustion chamber and chambers with annular cylindrical geometry, in which kerosene was burned in continuous multifront detonation modes. It was found that during detonation combustion of kerosene in cold air, the specific impulse values in annular cylindrical combustion chambers are higher than in radial combustion chambers. At hydrogen and air flow rates close to stoichiometry at the start of the combustion, autoignition followed by a transition to continuous spin detonation was observed. The transition time was reduced to 10 ms by forced (spark) initiation of the hydrogen-air mixture.
V. V. Parakhin1,2, V. M. Volokhov1, E. S. Amosova1, D. B. Lempert1 1Federal Research Center for Problems of Chemical Physics and Medical Chemistry, Russian Academy of Sciences, Chernogolovka, Russia 2Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
Keywords: fluorodinitromethyl-ONN-azoxy compounds, composite solid propellant, STT, plasticizer, enthalpy of formation, density, quantum-chemical calculations, thermodynamic calculations, specific impulse, effective impulse
The energy potential of ten fluorodinitromethyl-ONN-azoxy compounds as binder plasticizers in model composite solid propellants of various formulations, with and without metal (aluminum hydride or metallic aluminum). The energy potential of these plasticizers was compared with that of the most energy-intensive known plasticizers (nitroglycerin, tetranitromethane, and dinitrofurazan) for model solid propellants intended for different stages of rocket systems. It was shown that almost all of the studied fluorodinitromethyl-ONN-azoxyfurazans, when used as active binder components, provide higher energy values than nitroglycerin and tetranitromethane, and some fluorodinitromethyl-ONN-azoxyfurazans even outperform dinitrofurazan. High-performance quantum-chemical calculations of the enthalpy of formation of new, not yet synthesized energy-intensive substances that are promising in various fields of application were carried out.
M. V. Antipov, S. V. Erunov, D. N. Zamyslov, V. A. Ogorodnikov, D. A. Polshkov, A. V. Fedoseev, E. A. Chudakov
Nizhny Novgorod State Technical University n.a. R.E. Alekseev, Nizhny Novgorod, Russia
Keywords: shock wave, dusting, nitrogen, particles, flow, density, synchrotron radiation
The paper presents the results of measuring the velocity and density distributions in high-velocity (1.7 ÷ 4 km/s) shock-induced particle flows ejected from the free surface of tin and copper liners into vacuum (less than 103 Pa) or nitrogen (105 and 8 ⸱ 105 Pa). Periodically repeating triangular grooves 50 μm deep and 250 μm wide (2a0 / λ = 50/250 μm) were applied to the liner surfaces. Multi-frame recording using synchrotron radiation and laser heterodyne interferometry were used in the experiments. A pressure of ≈45 GPa in the shock waves emerging on the free surfaces of the liners led to the melting of tin, while copper remained in the solid state. A significant difference in the structure of the flows ejected from the surface of copper and tin liners and their deceleration velocities in the gas is observed.
A. L. Gamov1,2, A. B. Georgievskaya1,2, T. V. Karsanova1,2,3 1All-Russian Scientific Research Institute of Experimental Physics, Sarov Russia 2Nizhny Novgorod State Technical University n.a. R.E. Alekseev, Nizhny Novgorod 3Lomonosov Moscow State University, Moscow, Russia
Keywords: shock wave, hydrodynamic instability, particles, liquid, metal, radiography
The results of numerical simulations of experiments conducted using proton radiography and synchrotron radiation to record the motion of a flow of fine metal particles in gaseous media are presented. Particle ejection occurred as a result of a shock wave acting on the free surface of metal samples with small-scale, profiled initial disturbances. Numerical simulations were performed using a developed model of particle flow evolution in a gaseous medium, based on a model of the source of shock-wave dusting of metals, based on the physics of Richtmyer-Meshkov instability, and the laws of fragmentation of a single liquid droplet in a gas flow. The proposed model is shown to be in good agreement with experimental results.
A. V. Attetkov, A. V. Kotovich, E. V. Pilyavskaya
Bauman Moscow State Technical University, Moscow, Russia
Keywords: shock wave, two-phase porous material, melting, temperature field
The article presents the summarized results of a numerical analysis of the formation of a temperature field in a shock-compressed two-phase porous material in the absence and presence of phase transformations during plastic pore filling. Using mathematical modeling methods, the influence of mesoscopic processes of thermal dissipation and heat transfer on the resulting temperature field is investigated, and its topological features are determined in the presence of molten zones in the shock-compressed porous material.
S.-Z. Wu1, Z.-R. Gao1, Y.-K. Yang2, F.-Y. Zhang1, J.-X. Wu1, J.-Y. Huang1, Y.-C. Li1 1College of Field Engineering, Army Engineering University of PLA, Nanjing, China 2Key Laboratory of Chemistry for NBC Hazards Protection, Beijing, China
Keywords: damage characteristics, reinforced concrete beam, explosive impact load, dynamic response, model testing, numerical simulation
The character, criteria, effects and other characteristics of damage to reinforced concrete beams under the action of explosive impact loading were studied experimentally and using numerical modeling methods. A fast method for obtaining the P-I curve of beam elements with arbitrary structural parameters is proposed. First, five model tests were conducted to study the dynamic response and damage parameters of two types of reinforced concrete beams with cross-sectional widths of 0.04 and 0.047 m under a 200 g TNT explosion at pre-detonation distances of 0.2 and 0.5 m and at blast locations above 1/2 and 1/4 of the span. The results showed that damage to the reinforced concrete beam was less with a cross-sectional width of 0.04 m and at a blast location above 1/2 of the span under the experimental conditions. The experimental results confirmed the effectiveness of the numerical modeling method. Based on a large number of numerical simulation results, the approximation formula for the P-I curve of reinforced concrete beams was simplified, and the influence of the following parameters on the P-I curve was investigated: stirrup reinforcement ratio ρs, longitudinal reinforcement ratio ρ, concrete axial compressive strength ƒ′c, beam span L, beam cross-section height b, and beam cross-section width a. As a result, a method for quickly determining the P-I curve of reinforced concrete beam elements is proposed, which can be applied in the field of blast protection design and rapid damage assessment.
S. Debbarma1, P. Kumar2, S. Kumar Ghosh1, S. Saravanan3, K. Jayachandran3, R. K. Bhogendro Meitei1 1Department of Mechanical Engineering, National Institute of Technology, Tripura, India 2Department of Mechanical Engineering, Galgotias University, Uttar Pradesh, India 3Annamalai University, Department of Mechanical Engineering, Tamil Nadu, India
Keywords: explosion welding, loading factor, mechanical properties, microstructure, intermetallic compound, heat-affected zone
This article presents an analysis of the influence of the loading factor, a key parameter of the explosion welding process, on the interface morphology and mechanical properties of similar and dissimilar joints. The loading factor (the ratio of the explosive mass to the impact plate mass) determines the impact velocity, dynamic bending angle, and jet formation. It influences the nature of the interface, namely the formation of straight, wavy, or intermetallic layers, and therefore the weldability of dissimilar metals. Correct selection of the loading factor ensures high-quality welding with minimal defects, while excessive or insufficient loading factors lead to incomplete bonding or deterioration of the interface quality. This article summarizes the main experimental results and offers recommendations for process optimization and future research directions.
V. A. Arinin1, A. O. Blikov1,2, I. A. Blinov1,2, A. B. Georgievskaya1,2, A. Yu. Gordeev1, N. B. Davydov1, A. V. Degtyarev1,2, S. V. Erunov1,2, V. N. Knyazev1, S. A. Korshunov1, E. V. Kulakov1, S. F. Manachkin1, A. B. Profe1, A. S. Pupkov1, R. V. Tilkunov1, B. I. Tkachenko1, O. A. Tyupanova1 1All-Russian Scientific Research Institute of Experimental Physics, Sarov, Russia 2Nizhny Novgorod State Technical University n.a. R.E. Alekseev, Nizhny Novgorod
Keywords: lead, spherical explosive device, quasi-isentropic compression, equation of state, cold compression curve, pressure, density
A method for studying the quasi-isentropic compressibility of condensed substances was tested using an experiment with a lead shell. This method utilizes multi-frame radiography and explosive spherical loading devices with gas symmetrization. At maximum compression, the average density of the lead shell was ≈52.3 g/cm3, with a compression ratio of ≈4.6. The total pressure in the lead at maximum compression was ≈3.2 TPa, with the cold component equal to ≈94% and the thermal component ≈6%. The pressure values were obtained from a one-dimensional numerical calculation, which accurately describes the compression dynamics of the lead shell, using the ROSA-MI EOS for lead.
For hemispherical cumulative liners of degressive thickness (decreasing from apex to base), an increase in the velocity of the leading portion of the forming cumulative jet is observed with increasing thickness difference between the apex and base of the liner, which is ensured by the process of its explosive compression becoming more spherically symmetric. Based on a numerical solution to a model problem of the inertial, centrally symmetric collapse of a shell in the shape of a spherical segment with a model material that does not resist all-round stretching, it is shown that the maximum velocity of cumulative jets from hemispherical liners of degressive thickness that do not undergo volumetric destruction should be higher than that of jets from conical liners -- at least 12 km/s for copper liners. The production of a coherent copper cumulative jet with a warhead velocity at the specified level was recorded in a numerical simulation of the explosion of a charge with a lining of degressive thickness, having a hemispherical outer surface and a semi-superellipsoidal inner surface with an exponent of 2.05 in the semi-superellipsoid equation.
A. I. Konurin, D. V. Orlov
Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Rock bursts, large-scale blasts, seismic monitoring, cluster analysis, machine learning, geodynamic risks, blasting operations, stress-strain behavior
The analysis of 10 years-long seismic monitoring data at the Sheregesh deposit revealed the spatiotemporal patterns in the blasting-induced seismicity. Response of rock mass to blasting features a high spatial nonuniformity conditioned by geological medium anisotropy and tectonic faulting. The use of the k-means algorithm enables segmenting rock mass into process zones and allows identifying stress concentration areas. The cluster-specific time patterns in seismic response are confirmed, and the median time of delay in activation of post-blasting shocks varies in different zones. It is proved that the correlation dependence between the blasting energy and the post-blasting shock parameters is statistically insignificant, which highlights prevalence of the local geomechanics influence over the external effect. It is found that each blast induces 9.4 aftershocks on the average, at a high standard deviation, which proves variability of rock mass response. The research findings are of current interest in mining practices at rockburst-hazardous deposits in the conditions of complex geology and high tectonics.
Sergey Viktorovich Albertin
Pavlov Institute of Physiology, Russian Academy of Sciences, St. Petersburg, Russia
Keywords: integrative brain functions, modeling, scientific knowledge, methodology, thought experiment, ideal and material models
The article considers human cognitive abilities when modeling is actively used to understand and transform the external world. It discusses the prospects and possibilities of cognitive models and real experiments in studying physical objects and brain functions, as well as the limitations of objective research methods in studying mental processes that play an important role in forming a holistic view of world in the human mind.,
Oleg Nikolaevich Gurov
State Academic University for the Humanities (GAUGN), Moscow, Russia
Keywords: cyborgization, cyborg, integrative methodology, posthumanism, anthropotechnical subject, cyborgian eclecticism, ethics of technology, agro-cyborg, transformation of experience
The article presents the phenomenon of cyborgization as a complex interweaving of technological and human practices. It is shown that the roots of cyborgization lie in ancient myths and prosthetic practices. Using examples from history and contemporary cases, the author argues that the expansion of capabilities through external devices alters ontological and epistemological frameworks: a synergistic effect arises, and subjective experience and cognition are transformed. Comprehending cyborgization within the framework of optimistic transhumanist discourse, technology critique, descriptions of hypothetical models such as the agro-cyborg, and the concepts of the anti-cyborg and “reverse cyborg” makes it possible to identify both the risks and potential of cyborg technologies. The author develops an integrative approach, that is, cyborgian eclecticism based on the interweaving of various theories and methodologies and the reflexive revision of priorities as new data emerges. This approach enables the development of recommendations for the integration of technologies into social processes in a way that promotes the protection of human values and takes into account the variability of the socio-technical context. Cyborgization thus appears not simply as a modification of the body and/or consciousness, but as a transformation of modes of being that requires philosophical understanding and flexible ethical guidelines.,
Aleksandr Anatolyevich Shevchenko
Institute of Philosophy and Law, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: relevant explanation, integrative model, ontology, epistemology, social epistemology, explainable AI (XAI), understanding, epistemic norms
The article examines the evolution of the concept of relevance in scientific explanation in contemporary philosophy of science. The author demonstrates how classical formal models, such as Hempel and Oppenheim’s deductive-nomological model, have given way to a pluralistic approach that acknowledges multiple, context-dependent criteria of relevance. Three major challenges to the traditional paradigm are analyzed: (1) the epistemic shift from explanation to understanding as a primary epistemic goal; (2) technological challenges posed by “black-box” AI systems and the rise of explainable AI (XAI); and (3) the social and ethical responsibility involved in selecting which factors count as relevant in scientific explanations. In response, the author proposes an outline of the integrative model of explanatory relevance, which synthesizes three interdependent dimensions: ontological, epistemic, and social-normative. Within this model relevance is reconceptualized not as an external pragmatic constraint but as an internal epistemic norm that determines what deserves attention in scientific inquiry.,
Georgii Vladislavovich Cherkasov
Institute of Philosophy, Russian Academy of Sciences, Moscow, Russia
Keywords: ontological antirealism, deflationism, quantifier variance, metaphysical antirealism, skepticism about metaphysics, relativism, metaontology, metametaphysics
The article focuses primarily on outlining the positions of critics of heavyweight ontology - deflationists and antirealists. The author shows that these positions do not entail the denial of metaphysics. The article begins with examples from the Russian-language discussion in which deflationism and antirealism in metaontology are associated with the denial of the existence of an independent reality - metaphysical antirealism. These examples fall within the general trend of confusing theses of scientific, metaphysical, and epistemological antirealism, as well as antirealism with respect to specific types of entities (sometimes relativism and skepticism are also included). Next, a terminological policy is proposed for distinguishing between ontology and metaphysics, as well as metaontology and metametaphysics. It is argued that these terms usually play a coordinating role in the discussion and do not require definition. At the same time, clarifying the coordination terms helps advance from debates about words to debates about substantive issues.,
Inna Gennadievna Merkoulova
International Center for Semiotics and Intercultural Dialogue of the State Academic University for the Humanities, Moscow, Russia
Keywords: digital culture, meme, mediatization, meaning, semiotics
The new issue of the Latin American semiotic journal “deSignis” (No. 41, July-December 2024) focuses on the topic of digital culture and memes. Leading semiotic experts from Argentina, Brazil, Mexico, Uruguay, and several European countries reflect on the phenomenon of the meme as part of the general digital culture in the context of the production and dissemination of meaning. The articles in the issue represent the so-called “third-generation semiotics”, which in the 21st century strives for an interdisciplinary dialogue with philosophy and anthropology.,
Vladimir Moiseevich Reznikov
Institute of Philosophy and Law, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: physics, mathematics, probability theory, applied statistics, axiom, independency, causality, artificial intelligence
In the 1900s, D. Hilbert formulated his famous problems, and the sixth problem was intended to axiomatize probability theory as a physical science. In 1938, the axiomatics proposed by A.N. Kolmogorov were accepted as a working mathematical science. This raises a question that has been neglected in the established philosophical literature - why did Hilbert consider probability theory a physical science? The main goal of this work was to describe the characteristics of probability theory that are specific to the strong natural sciences. The author first presented some well-known considerations and examples on this subject. They were based on the concept of holism, which held that results, such as those obtained in statistical physics using probability theory, were not separated from probability theory itself. However, they are not sufficiently complete and thorough to consider probability theory a physical science. Then, the author formulated his own arguments. Thus, based on an analysis of the content of Bernoulli’s and Chebyshev’s theorems, he demonstrated that they allow for verification of the conditions of their applicability to the data being studied, and, in principle, a more complex verification of the adequacy of the results proven within them to these data. In addition, he demonstrated that a number of concepts of this science, such as independence and probability, allow for a general scientific interpretation. Therefore, probability theory is a mathematical science, which follows from the formal and abstract nature of its axioms, but it has some features characteristic of strict natural scientific and technical disciplines. The second part of the article is devoted to the study of the reasons for changing the status of applied statistics, since over the past decades in Western universities this science is no longer considered part of mathematics. As a result, on the basis of a substantive analysis of classical statistics, the author has shown that there are far more reasons for this discipline than for probability theory not to be considered an exclusively deductive science.,
Igor Felixovich Mikhailov
Institute of Philosophy, Russian Academy of Sciences, Moscow, Russia
Keywords: physics, ontology, perception, theory, waves, particles, duality
Classically, physicists strived to assign some rigorous explanatory models to what happens in our phenomenal scope, and they surely succeeded. Nowadays, cognitive science tells us that our phenomenal representations, even being presumably structurally veridical, are made out of our inborn “mental paints” (Harman), such as light, colours, warmth, density, etc. According to professionally trained physics, the wave-particle duality is not at all paradoxical mathematically, only is it perceptually. Thus, one may conjecture that the rest of items of our physical ontologies may have been induced by our perceptual constitution, and if bats or robots did physics, their science, the set of its problems and their representations of facts could have substantially differed. Our physics uses categories (particles, waves) that feel natural to us because they’re built from our “mental paints” and predictive habits. A robot’s correlation-based science would skip these, suggesting our ontology isn’t inevitable. If perception is an evolved interface (Hoffman) and knowledge is a data-trained predictive model (Friston), then bats or robots would indeed craft different sciences. Our “problems” (e.g., wave-particle duality) might not even register with them. Big Data science hints that theory itself - our need to explain with entities like “fields” - might be a human peculiarity. An AI could deal with the same reality without our conceptual baggage, echoing Hoffman’s idea that we don’t see the “real” code. In sum, this suggests that the ontology of physics isn’t a direct window into reality but a human-constructed map, shaped by how evolution painted our interface and how our brains model the world. The mathematics might be universal (e.g., quantum equations), but the entities we project beyond - like waves or particles - are our own. Moreover, match or mismatch of an ontology and a theory can affect the latter’s efficiency.,
