Том 524, № 2 (2025)

The paper compares the young structures of the Terceira rift and the ancient ones – the King's trough. It was shown that despite the significant difference in the time of their formation, they have much in common. They are located obliquely in relation to all the structures that formed within the Mid-Atlantic Ridge, have a similar extent, and combine parameters characteristic of both continental (superslow rate of extension, thickness of the lithosphere, alkaline volcanism) and oceanic rifts (segmentation, magmatism localized in a narrow area). The stages of formation of the structures are similar. They were formed on the already existing oceanic crust. The initial stage in both cases is associated with diffuse plume tholeiitic magmatism, distributed in some extension area with the formation of large linear uplifts. The second stage was characterized by almost complete cessation of magmatism and localization of extension in a single narrow area. Alkaline magmatism of the central type is typical for the final stage. Both of these structures are part of triple junctions, being fragments of the boundaries of lithospheric plates. The noted similarities indicate the recurrence in time of the kinematics of the movement of lithospheric plates in the North Atlantic with the formation of structures at the plate boundaries that are different in age but similar in geological history and formation mechanisms.

The first results of U–Pb (LA-ICP-MS) age determinationof zircon grains from acid volcanics occurring in the lower part of the Upper Precambrian basal strata section of the Subpolar Urals (in the Puivinskaya formation) are presented. The obtained age of 647±3 Ma records the time of the earliest manifestations of acid magmatism in the Late Proterozoic history of the formation of the Subpolar Ural segment of the earth's crust, and also determines the upper age limit of the rocks hosting the volcanics. Taking into account the previously obtained U–Pb (LA-ICP-MS) dating results of detrital zircon grains from meta-silestones of the Puivinskaya formation (the average weighted age of the three youngest zircon grains is 883±71 Ma), the possible time interval of its formation has been clarified: 950–650 Ma. The obtained data allow us to estimate the time of the Timan passive margin formation.

The first detailed δ¹³C_org record in the lower part of the Permian of Western Verkhoyanie was obtained based on the study of 103 samples of siltsrone rocks from the Srednyaya Dielendzha section, which is the prototype of the Khorokyt Formation and the Khorokytian Regional Stage. Carbon isotope correlation with the previously studied Kubalakh section of Northern Verkhoyanie showed that in the prototype of the Kubalakh Formation of the lower reaches of the Lena River, the Jakutoproductus budnikovi Beds and the Jakutoproductus talchanensis Beds fall on a break in the outcrop. The paleontologically uncharacterized upper part of the Srednyaya Dielendzha section belongs to the upper half of the Jakutoproductus insignis Zone. For the first time, chronostratigraphic relationships between the biostratigraphic units of Verkhoyanie and the conodont zones of the boundary Asselian-Sakmarian deposits of the Southern Urals have been established using chemostratigraphic methods. Carbon isotope data indicate that the Khorokytian Regional Stage of Verkhoyanie fully corresponds to the Asselian stage of the International Chronostratigraphic Chart.

The article reports a unique discovery of isotopic anomalies established by studying the ratios of three stable sulfur isotopes (³²S, ³³S and ³⁴S) in authigenic sulfides from sedimentary rocks formed at the end of the Permian (~252 million years ago) in northeastern Asia (Suol section, Southern Verkhoyanye, Eastern Siberia). The range of δ³⁴S variations reaches 65‰, the deviation of Δ³³S values from zero values varies from 0.11‰ to 0.46‰. The presence of sulfur isotopic anomalies at high paleolatitudes of the Boreal Superrealm is recorded for the first time. The anomalies indicate intense UV fluxes penetrating the Earth's atmosphere, which may be related to the weakening of ozone protection as a result of the decrease in magnetic field intensity and the release of large amounts of gaseous sulfur compounds and halogens into the atmosphere during massive volcanic eruptions. Active hard UV radiation had a direct, deadly effect on both terrestrial and marine (primarily surface plankton) biota.

We report new data on the mineralogy, petrography, geochemistry, U–Th–Pb geochronology, and Sm–Nd and Rb–Sr isotopy of granitoids and associating rocks of the Sup, Duzunya and Batyrchan plutons, including rocks with rapakivi texture, which we combine into the new Severookhotsk complex. These rocks were formed in the Centomalian–Coniacian ages 94–88 Ma (U–Pb SHRIMP-II data) in the back-arc of the West Okhotsk flank zone of the Okhotsk–Chukotka volcanoplutonic belt. Sm–Nd and Rb–Sr isotopic data confirm the presence of both an enriched mantle and a continental component in the composition of the magmatic source of the rapakivi granites. We show that the Severookhotsk complex magmatism and the Sn-polymetallic and Au–Bi mineralization of the Allakh-Yun tectonic zone have the same origin.

In the south of the Russian Far East, metalliferous (titanium, gold, platinum, etc.) Late Mesozoic intrusions of ultrabasic basites have been identified within the Sikhote-Alin orogenic belt. In the outer contour of one of them, the Ariadna dike, there are dikes of fluidoexplosive breccias of alkaline picrites, characterized by a fairly high degree of carbonation and enrichment with rare earth elements (REE), as well as Ba, Sr, Zr, V, Cr, Nb, Zn. The most common minerals concentrating REE are monazite-(Ce) and lucasite-(Ce). The total content of lanthanides, dominated by light REE, varies synchronously with the concentration of carbonaceous matter in the form of graphite. Isotope-carbon studies indicate the involvement of mantle and crustal processes in the formation of graphite-rare earth mineralization. It is assumed that the association of graphite with REE minerals can serve as one of the indicators in the predictive assessment of the total ore potential of ultrabasic magmatism. The presence of industrially promising high-carbon ore formations will also have a significant impact on the development of technology for extracting useful components.

The paper presents the results of paleomagnetic analysis of metasandstones of the middle and upper parts of the Sakukan suite of the Udokan complex Kodaro-Udokan trough of the western part of the Aldan shield. The rocks of the Sakukan suite were deposited in a relatively narrow time interval of 1.90–1.88 Ga, during which of folding and greenschist facies metamorphism also occurred. According to high-temperature components of remanent magnetization and remagnetization circles of 8 sites, the average direction is: D = 192.7° I = 21.5° k = 18.0 α₉₅ = 13.4°, fold and reversal tests are positive. Pole calculated by averaging virtual geomagnetic poles of 8 sayts (Plat = −21.0° Plong = 104.8° A₉₅ = 11.4°) coincided with the poles of the Early Proterozoic granites of the Kodar complex and gabbroids of the Chiney complex of the Udokan, the age of which is 1867–1876 Ma. According to our data, the Olekminsky block was located 1.90–1.88 Ga ago in near-equatorial (11°) latitudes. The Sakukan suite of the Kemen series of the Udokan complex is probably the most ancient geological object from which it is possible to obtain a reliable paleomagnetic pole for the Siberian craton.

A fragment of the partially mineralized lower molar M₁ of a fossil pig Sus sp. is described from the main bone level of the Taurida cave locality (central Crimea, Russia), dated to the Late Villafranchian (Early Pleistocene, MO1 zone, 1.8–1.6 Ma). Like the materials from the coeval Dmanisi locality in Georgia, this extremely rare find (so far the only one of many thousands of vertebrate remains from the Taurida cave) may indicate a sharp decline in number (but not complete disappearance) of Suidae in Eastern Europe and Western Asia around 1.8 Ma, which clarifies the ideas associated with the “suid gap” hypothesis about the absence of pigs in Europe in the interval of 1.8–1.2 Ma.

On the basis of gravitational data, seismic data and geochemical models of the mineralogical composition of the mantle of Mars, the internal structure models were constructed. The effect of the mantle mineralogical composition on the model value of the Chandler Wobble period was investigated. Andrade rheology was used to account for the inelasticity of the interiors when calculating the tidal Love number k₂ and the period of Chandler Wobble. Variations in the composition of the planet's mantle lead to a change in the value of the period of the Chandler Wobble by 1–1.5 days.

In order to study the consequences and conditions of the Beltir earthquake, at the IPE RAS an epicentral expedition to the Altai Mountains was organized. The intensity of earthquake in populated areas reached VI–VII. In general, there was minor damage to buildings, furniture and other household items; some people experienced fright and poor health. In the epicentral zone secondary effects have occurred. They formed a compact area covering different geological and geomorphological conditions. The intensity in the epicentral area is VII. The seismic source is a locally activated structure, pronounced on the surface by an arch-shaped anticlinal fold measuring approximately 2.6×4.5 km.

The study focuses on developing and experimentally validating an ultra-long-range hydroacoustic communication method capable of data transmission over distances exceeding 1,000 km in the complex acoustic environment of Russia's coastal seas. The proposed method employs frequency manipulation with tonal pulses in a narrow low-frequency band (300–500 Hz), ensuring robustness against multipath propagation, intersymbol interference, and Doppler distortions. A key feature of the method is the use of signal frames containing synchronization M-sequences and information components processed via the Goertzel algorithm for dominant frequency detection. Experimental verification in the Sea of Japan achieved record-breaking message transmission over 1073 km with a signal-to-noise ratio near 0 dB, demonstrating just 1–3% decoding error probability at 4 bits/s. The results confirm the feasibility of establishing an information support system for underwater vehicles across Russia's entire exclusive economic zone, with strategic implications for marine reconnaissance, navigation, and monitoring. This method enables covert one-way communication with autonomous underwater vehicles, including long-range gliders.

Analysis of temperature measurements at a mooring in the Norwegian Sea was performed. The buoy station operated for two years at 73°22′ N, 7°18′ E, with the mooring replaced after a year of operation. The mooring was positioned south of the critical latitude (74°30′ N) for internal tides with the M2 frequency. Temperature variations, which reflect fluctuations associated with internal waves, varied depending on the vorticity at the measurement point. Cyclonic and anticyclonic eddies were alternately located in the study area. In the presence of anticyclonic eddies, peaks in the temperature spectra caused by internal waves were noted. When a cyclonic eddy approached, the peaks disappeared, despite the buoy positioned south of the critical latitude.

A scheme for the subdivision of soil organic matter (SOM) into structural, process-related, and functional pools has been developed. In particulate organic matter (C_POM) and mineral-associated organic matter (C_MAOM) belonging to the group of structural pools of SOM contain, on average, 28% and 70% of total soil organic carbon (C_ORG), respectively. The carbon contents in the process-related pools of potentially mineralizable organic matter (C_PM), microbial biomass (C_MB), and chemically oxidizable organic matter (C_OX) were 4.6%, 1.4%, and 81%, respectively. The sizes of the structural and process carbon pools correlated with each other and with C_ORG. The three functional SOM pools (active, slow, and passive) contained approximately 5%, 76%, and 19% of C_ORG, respectively.