Vol 516, No 1 (2024)

The oldest granitoids of Kan-Сhingiz complex in Chingiz-Tarbagatay region of Eastern Kazakhstan, composed of quartz diorites, granodiorites, plagiogranites and granites, are first dated. U-Pb (ID-TIMS and SIMS) geochronological study of granites and plagiogranites is carried out and age estimates 509±2 and 512±3 Ma, approximately corresponding to the boundary of Early and Middle Cambrian, are obtained. These data allow to consider the age of volcanic-sedimentary sequences, host for granitoids, as Early Cambrian. Composition affinities of granitoids of Kan-chingiz complex indicate their formation within ensimatic island arc.

Detrital zircon dating allows us to elucidate the age and provenance of siliciclastic strata of the Sarydjaz and Ichkebash formations in the Middle Tianshan of eastern Kyrgyzstan, previously thought to be of the Middle or Late Ordovician age. New data indicate that the upper part of the Ichkebash Formation contains Lower Silurian strata, previously unknown in this region. The Kanachu Formation, which lies stratigraphically above, is also not older than the Silurian in age. The absence of marine fauna at these levels apparently reflects the predominant development of deltaic facies. The paleocurrent indicators and the ages of detrital zircons point at the provenance in the North Tianshan (NTS). Grains with ages from the Late Cambrian to the Silurian, synchronous with the main stage of the Early Paleozoic magmatism in the NTSh, predominate in the Ichkebash Formation. The occurrence of Precambrian detrital zircons in all dated samples and especially in the Sarydjaz Formation indicates the erosion of Precambrian rocks. The provenance most likely located in the Chu-Kendyktas Massif, where Precambrian detrital zircons in Neoproterozoic and Early Paleozoic metasedimentary rocks demonstrate a similar age distribution. The foredeep in the Middle Tianshan was formed in the Late Ordovician and Early Silurian generally subsynchronously with the main orogenic event in the NTS.

The article examines the results of digital and technological modernization of the oil and gas industry within the framework of the state program "Digital Economy 2017-2024" in the implementation of measures proposed by academic institutes of the Russian Academy of Sciences on the basis of a comprehensive scientific and technical program of a full innovation cycle, as well as the potential of exploratory and applied research to prepare a new state program "Data Economy" for the period up to 2030 of the year. The activities are a set of interrelated scientific, technical, digital solutions and innovative technologies that ensure the achievement of goals, developed with the leading participation of the Institute of Oil and Gas Problems of the Russian Academy of Sciences and the Institute of Oil and Gas Geology and Geophysics named after. A. A. Trofimuk SB RAS, program “Digital and technological modernization of the world’s largest West Siberian oil and gas production center.” The main goal of scientific research for the oil and gas economy of big geodata is the creation and implementation of digital modeling technologies, the development of ecosystems, computing platforms and digital twins of oil and gas assets, and the transportation of hydrocarbons to existing and newly created petrochemical clusters in order to develop the domestic market for their complete processing into products with high added value and strengthening the digital leadership of Russian energy companies. The key factor hindering the innovative development of the Russian oil and gas complex is the lack of high-performance computing systems. The main oil and gas tasks that require the involvement of supercomputers with peta- and exascale performance levels (1015 and 1018 floating point operations per second, respectively) include the tasks of managing the “digital ecosystem” of the world’s largest West Siberian oil and gas production center and unique oil and gas fields in the real time. The development of the digital ecosystem is proposed to be formed on the basis of platform solutions and comprehensive scientific and technical programs and projects of a full innovation cycle. The main problems in the sphere of creating a digital energy economy of big data have been identified: an acute shortage of personnel with digital competencies in the field of oil and gas production, specialists in opticalization, multisensorization, supercomputing, cybersecurity and petrorobotics.

The presence of ammonites of the subfamily Collignoniceratinae has been established in the Turonian Stage of Western Siberia. These findings allowed us to recognize the Collignoniceras woollgari zone in the Middle Turonian of this region, as well as to recognize the peculiarities of ammonite dispersal in the Arctic and clarify the palaeogeography of the Turonian age. Based on the frequency of occurrence of Collignoniceras woollgari regulare in the boreholes in the north of Western Siberia, their penetration into the West Siberian basin through the Arctic from the Western Interiort Sea of North America is most likely. For the first time Collignoniceratinae were determined in the Upper Turonian of the Yangoda River (west of the Yenisei-Khatanga regional trough).

The paper presents isotopic U–Pb zircon data (LA–ICP–MS method) for the main types of high-potassic intrusive rocks of the Chorukh-Dairon W–Mo(–Cu–Au) skarn deposit situated in the Kurama segment of the Middle Tien Shan near the largest porphyry Cu–Mo–Au deposits of the Almalyk mineralized cluster. Together with the other Au, W, Mo and Cu deposits, all these deposits are parts of the extended Late Paleozoic metallogenic belt of Tien Shan. The concordant isotopic U–Pb zircon data obtained for the rocks of successive intrusion phases in the Chorukh-Dairon pluton span from about 298 Ma to 290 Ma. This interval included crystallization of monzodiorite (295.1±3.3 Ma), quartz syenite (294.7±2.3 Ma), quartz monzonite (294.1±2.1 Ma), and monzogranite (293.0±3.0 Ma). These dates correspond to the pluton emplacement at the Late Carboniferous-Early Permian boundary and highlight its younger age compared to the productive high-potassic intrusions of the porphyry Cu–Mo–Au deposits in the Almalyk mineralized cluster, the latter assigned to the Late Carboniferous (about 337–313 Ma and partially to 308–297 Ma). By contrast to the latter, which were intruded in the subduction-related environment, the emplacement of the high-potassic rock of the Chorukh-Dairon pluton occurred in the transitional subduction-related to post-collisional environment or even under an actual post-collisional regime. This allows distinguishing two pulses of ore-bearing Carboniferous-Permian high-potassic calc-alkaline to shoshonitic series magmatism in the Middle Tien Shan. Consistently, there is a metallogenic evolution in the region that was expressed in the transition from porphyry Cu–Mo–Au deposits associated with subduction-related potassic magmatism, and likely evolving toward epithermal Au–Ag deposits, to essentially tungsten (W–Mo–Cu–Au) deposits associated with younger potassic magmatism occurring rather in the post-collisional environment.

Primary studies of the concentrations of rare elements in the sediments of two lakes on King George Island (Kitezh and Glubokoe) showed that their geochemistry reflects the geological features of the area. Compared to the upper part of the Earth's crust, the studied sediments are enriched in Cu, Cd, V, Tl, Mn, Ti and P. Similar patterns have been identified in the geochemistry of volcanic and sedimentary rocks of the Fildes Peninsula. Trends in REE changes generally follow their behavior in rocks, but the overall REE concentration in sediments of lakes is higher, which may be due to the presence of organic matter accumulating in sediments of water bodies. Unlike the aquatic environment, the chemical composition of sediments does not reflect the significant influence of the activities of polar stations. However, small increases in Pb and Sb concentrations in the upper sediments suggest the influence of long-range atmospheric transport of the contaminants.

Dating of magmatic rocks from paleo-island arcs of orogenic belts helps to define the precise timing of subduction processes that took place during the formation of the orogen. Within the central (East Trans-Baikal) part of the Mongol-Okhotsk orogenic belt, the Kamensk island-arc terrane is an example of such paleo-island-arc complex. Its intrusive part is included into the Bereinsky complex, represented by a gabbro-diorite-tonalite-plagiogranite series of rocks demonstrating subduction geochemical characteristics. The dating of zircons from acidic rocks of this complex by the U–Pb classical method showed that they were produced in a narrow time interval – 203±1–205±1 Ma, which corresponds to Norian/Rhaetian boundary of the Late Triassic. Taking into account the previously obtained age of the diorites (254±5 Ma), the timing of formation of the entire series of intrusive rocks is about 50 Ma, thus indicating in the Late Permian – Late Triassic the subduction along the northern (in modern coordinates) margin of the Mongol-Okhotsk Paleocean beneath the Siberian paleocontinent. Diorites of the first phase have positive values ɛ_ND(254MA) = 3.2–3.6 (T_Nd(DM) = 879–994 Ma), and plagiogranites – ɛ_ND(205MA) = 2.3–3.5 (T_Nd(DM) = 859–1028 Ma), which points to the connection of these rocks with the substance of the depleted mantle source and is consistent with the Sm-Nd isotope characteristics of the juvenile crust of the Central Asian orogenic belt. This study was supported by Russian Science Foundation, grant no. 22-27-00775. The resources of the Shared Use Center for Isotope-Geochemical Research (Vinogradov Institute of Geochemistry, Siberian Branch, Russian Academy of Sciences, Irkutsk) were used in this work.

The helicity of atmospheric disturbances caused by inhomogeneities in the gravity field is theoretically estimated. For this purpose, a three-dimensional stationary analytical model of linear disturbances introduced by spatial inhomogeneities of the gravity field into the background geostrophic flow of a stratified rotating medium (atmosphere) was used. From the solution found, it follows that in highly anomalous regions the amplitude of the helicity of emerging disturbances can be noticeable.

A quantitative assessment of the transformation of the bottom pressure variations, generated by infragravity waves into displacements of the upper layer of the Earth's crust has been made on the basis of experimental data, obtained with a laser meter of hydrosphere pressure variations and two laser strainmeters. The dependence of the coefficient of transformation of bottom pressure into elastic vibrations of the Earth's crust on the periods of infragravity waves was determined.

Measurements of temperature pulsations under conditions of summer hot weather in the near-surface air layer in a deserted area were carried out using wire sensors distributed spatially and in height with a recording frequency of 1000 Hz. For the power spectra, slopes with values from “–1” to “–1.35” (scale: 0.2–2 m) are noted for frequencies below the “–5/3” inertial interval region. At frequencies above the inertial interval (scales: 0.01-0.1 m), slopes range from “–4.2” to “–5.8”. In some episodes at frequencies less than 0.1–0.3 Hz, slopes from “–0.2” to “–0.85” are observed. Based on the equations of motion in the Boussinesq approximation, we obtained estimates for the observed slopes of the spectra: “–1”, “–4/3”, and “–7/3”, characteristic of a thermally stratified medium. Using a qualitative (visual) method at different signal averaging times (1, 10, 200 s), the occurrence of thermoconvective structures of “ramps” with a temporal length of 0.3–1 s was revealed, which constitute ramps with a length of 1–10 s at larger averaging.

Using the data from weather observation stations, an assessment of the statistical significance of the first harmonic amplitude of the average long-term daily precipitation amount series in Russia in 1961–2020 and their changes in 1991–2020 compared to 1961–1990 is made. It is shown that at most stations the first harmonic has a reliable value different from the noise, except for eleven stations in the southern regions of the European Part of Russia. It is revealed that, on average, there is a significant decrease in the first harmonic amplitudes of the daily precipitation series across Russia. An analysis of the spatial distribution of the studied quantities is performed and the presence of large areas with their homogeneous character is demonstrated.

The high-resolution pollen record retrieved from dated sediments of the Khanka Depression made it possible for the first time to reconstruct evolution of vegetation in the south of the Russian Far East that occurred during one of the coldest phase of MIS 2 – the Yonger Dryas. The results of palynological analysis showed that strong global cooling occurred after the first, slight warming between 18200 and 15500 cal BP, which followed after one of the coldest and driest Gydan Stage of the Sartan Glaciation, again led to spread of boreal flora plants. The spruce and small-leaved forests, sparse larch and dwarf birch, alder and elfin pine forests, and also Sphagnum mires dominated in the ecosystems of the region. This plants were typical of the south of the Russian Far East during the drier and colder Gydan Stage of the Sartan Glaciation. Their ranges under the cold climate, which were significantly different from the modern ones, due to increasing cooling, again began to shift southward.

Among the species of the genus Crotalaria L., Crotalaria juncea is the only cover crop cultivated for its fiber. The quality of the latter depends on nutritional conditions, the accumulation of biophilic elements in the biomass and the synthesis of proteinogenic amino acids. Thus, the purpose of the study was a qualitative and quantitative assessment of the green harvest at the stage of active flowering, before the phase of bean formation, when the entire biochemical cycle of the plant is reconfigured, and biochemical indicators are maximum. The plants were grown for 140 days (from April 22 to September 9, 2023) in protected soil conditions. The experimental design consisted of two blocks of 50 plants: in the first (control) plants were grown in a soil mixture without any additives; in the second, the crop was treated three times during the growing season with an organic suspension of humic acids (1000 ppm) obtained from sapropel (Pskov region) – UDGSS, by applying it when watering at the root. The soil substrate in both cases was typical chernozem (Kamennaya Steppe nature reserve, Voronezh region, 51°01ʹ41.6ʹʹN 40°43ʹ39.3ʹʹE) with a 20% addition of volcanic zeolite. Over the course of every 14 days, a systematic record of the dynamics of changes in the morphometric indicators of crop growth (height and dry biomass) was carried out, by removing five cultivars from each block of variants. After 140 days, the remaining five replicates per variant were subjected to biochemical analysis using inductively coupled plasma mass spectrometry (ICP-MS) and high-performance liquid chromatography (HPLC) using 7500 and LC 1200 instruments (Agilent Technologies, USA), according to the manufacturer's method. Treatment with UDGSS increased productivity and shoot height by 51.1% and 11.3%, respectively. The concentration of macroelements in dry biomass was in the following order: Na>K>Ca>S>P>Mg in the control and Na>K>Ca>Mg>P>S in the variant with UDGSS, and the export of microelements – Fe>Mn>Zn> Ba>B>Cu>Mo and Fe>Mn>B>Zn>Ba>Cu>Mo. At the same time, in total, the increase was more manifested in the amount of accumulation of microelements, due to a twofold increase in the concentration of iron ions. Among amino acids, an increase in the concentration of L-Lysine, L-Glycine, L-Glutamine and L-tyrosine was observed. The first three are structural components of biological tissues, which indirectly indicates an increase in the fiber strength of the culture.

Charcoal is a common material for radiocarbon dating and is underestimated as an object of dendrochronological analysis – a method that allows dating natural and historical-archaeological events with an accuracy of up to a year. The new approach to charcoal sample preparation developed by the authors removes previously existing restrictions on the use of this fragile material in dendrochronological studies and allows it to be used as an effective source of information in paleoecology, paleoclimatology, paleogeography and archaeology. Applying this approach, a 377-year tree-ring chronology was constructed using archaeological coals from ancient iron-smelting furnaces in the Chuya-Kurai ferrous metallurgy province of the Russian Altai. This is the first tree-ring chronology of charcoal in Russia and the longest in the world dendrochronological practice. Its further analysis will provide new information about the nature and archaeological events of the high mountain region located in the center of Eurasia.