This is a synopsis of the available data on crustal carbonatites, including their temporal and spatial distribution, mineralogy, geochemistry, and stable isotope (δ¹⁸O and δ¹³C) patterns. Crustal carbonatites are intrusive rocks containing >50 vol. % carbonate minerals and ≤20 wt. % SiO₂, which crystallize from partial melts of primary sedimentary carbonate rocks in the lower crust. They commonly occur as dykes in high-grade metamorphic complexes, bear silicate minerals typical of metasomatic environments, show isotopic and geochemical signatures of carbonate sediments or transitional varieties to mantle-derived carbonatites, and are emplaced during tectonic activity in strike-slip, rifting, or postcollisional extension settings. Partial melting of carbonate material in the crust and intrusion of melt batches to shallower crust levels is possible provided that primary carbonate sediments are present in the lower crust while the melting region is heated up by underplated mantle mafic magma and is fluxed sufficiently with H₂O-rich fluids.

The paper presents the results of the study of geochemistry and U-Pb zircon dating of Cretaceous igneous rocks of the westernmost part of the Badzhal terrane within the Badzhal and Dusse-Alin volcanic zones of the Khingan-Okhotsk magmatic belt. The granites of the Verkhneurmysky pluton and Pravourmyskaya dyke in the Badzhal zone were dated at 100±1 and 93±1 Ma, respectively. The age of diorite in the Suluk-Egono interfluve of the Dusse-Alin zone was estimated at 88±1 Ma, and the ages of three tuff zircon populations were estimated at 88±2, 97±1 and 105.5±1.3 Ma. The dating results indicate that the synorogenic reduced granites of the Verkhneurmysky ore cluster were formed under the transform continental margin regime, which gave rise to the occurrence of a large Albian-Cenomanian magmatic province of Pacific Asia. The magnetite series diorites of the Dusse-Alin zone were formed during the subsequent subduction-related Turonian-Maastrichian stage, but their geochemical characteristics are not typical of suprasubduction magmas. This may indicate a later transition to subduction at this section of the continental margin, or the existence of local extension and/or transcurrent faulting in the subduction settings. The studied igneous rocks of both stages and volcanic zones were formed with significant involvement of material from the mature continental crust, and are characterized by a similar range of ε_Nd(t) values from –0.9 to –2.6 and two-stage Nd model ages from 1.22 to 1.05 Ga.

The Late Devonian – Early Carboniferous intrusive magmatism in the West Magnitogorsk zone of the Southern Urals is associated with post-island arc restruction of the earth’s crust during the assembly of the Laurasia supercontinent. Magmatic bodies usually have a submeridional orientation, and the rocks are compositionally variegated and display mixed geochemical characteristics of supra-subduction and intraplate magmatism. A small proportion of magmatism falls within plagiogranites, the earliest of which correspond to the Kizil complex, which records the continental-type crust formation at the base of the Magnitogorsk island-arc terrane. It has been found that thin dikes and sills of the Kizil complex occur widely in the central part of the West Magnitogorsk zone and are represented by metasomatized plagiogranites with wide variations in alumina content (12–18 %), iron content (Fe# 0.7–0.9) and total REE (117–347 ppm). The ID TIMS method yielded four U-Pb zircon ages of which the 345±6 Ma value agrees most satisfactorily with the geological data; other values may be associated with the assimilation of host rocks and metasomatism of granites. Based on the microelement (variable minimums for Eu and Sr, minimums for Ti, Nb and Ta) and isotopic composition of Sr, Nd (εNd₍₃₄₅₎=5.9–6.0, ⁸⁷Sr/⁸⁶Sr₍₃₄₅₎=0.7041–0.7051), it was concluded that that the main source of the Kizil granitoids could be amphibolized mafic rocks of the ophiolite association, thrust onto the margin of the Laurussia paleocontinent along the Main Ural Fault zone to the west of the West Magnitogorsk zone.

Herein we report the results of LA-ICP-MS dating of detrital zircons from eight stratigraphic levels of the Proterozoic section of the Igarka uplift (northwestern Siberian Platform). The age spectra include the Meso- and Neoarchean (3100–2600 Ma), Paleoproterozoic (2100–1700 Ma) and Neoproterozoic (1000–600 Ma) ages. However, the age distribution drastically varies among the samples. The Neoproterozoic zircons, associated with the hypothetic orogenic belt at the platform periphery, dominate in the lowstand system-tract continental and marginal marine strata (Gubinskaya, basal Chernaya Rechka, and Izluchina formations). In contrast, the zircons in the Riphean and Vendian marine strata (Bezymyanny, Ludy, Korablik, and Sukharikha formations) mostly originate from erosion of the crystalline basement of the Siberian Platform. The concordant mafic bodies in the Upper Riphean (Criogenian) Gubinskaya formation contain the concordant cluster of zircons of 835±4 Ma. It contradicts with the maximum deposition age of 716±10 Ma of the host strata, hence the zircons in the mafic bodies supposedly comprise xenocrysts.

On one hand, heavy minerals of terrigenous rocks make it possible to obtain unique information on configuration of the direction of clastic sediment transport into the basin and on the other to reconstruct the time for erosion of petrocomplexes of the provenances. In order to reconstruct the paleogeographic setting of the Southern Cis-Urals and the orogenic evolution of the Paleo-Urals at the Permian-Triassic boundary, the authors evaluated the composition and stability of the provenances for the Permian-Triassic terrigenous rocks of the Boevaya Gora section (Orenburg region) based on the analysis of the heavy minerals – zircon and garnet. Heavy mineral samples were taken from sandstones of three stratigraphic levels: Upper Permian, Lower Triassic, and paleontologically barren interval in the immediate vicinity of the Permian-Triassic boundary. The results of U-Pb LA-ICP-MS dating of detrital zircon and analysis of garnet end-members proportions have shown that the provenances covered the petrocomplexes of the tectonic zones of the Ural foldbelt – Uraltau, Main Uralian fault and Magnitogorsk, which allows reconstructing the Paleo-Urals orogen main-watershed axis position at the Permian-Triassic boundary east of that of the present day. It is shown that the source areas near the Boevaya Gora section remained stable during the whole time of accumulation of the studied part of the section. This conclusion is confirmed by the results of measuring the anisotropy of magnetic susceptibility in the studied rocks, which also suggest the strengthening of hydrodynamic regime in the terminal Permian and predominantly meridional direction of the clastic sediment transport.

The paper presents new data on the composition of Late Paleozoic terrigenous and volcanogenic-terrigenous rocks of the Upper Devonian-Lower Carboniferous Tocher formation of the Bagdarin synform (Western Transbaikalia). The authors consider petrographic and lithogeochemical features of the rocks, and clarify the conditions of depositional environment, source area, and tectonic settings that controlled sedimentogenesis. It has been established that terrigenous rocks of the Tocher formation were formed from decomposing igneous and volcanogenic rocks. The petrographic and lithogeochemical characteristics of the Late Paleozoic sedimentary rocks of the Tocher formation make it possible to classify them as greywacke, arkose, tuffaceous and silt sandstones. The distribution of petrogenic oxides, as well as rare and rare-earth elements, together with the results of petrographic studies of thin sections indicate that mixed (felsic, intermediate, mafic) magmatic rocks were decomposed in the source area. The sediments in the first member of the Tocher formation, were predominantly derived from felsic source rocks, and those in the second and third members – from mafic and intermediate source rocks. The Riphean island-arc volcanics of the Usoy and Burom formations, as well as gabbro-diorites and diorites composing the Shaman basement protrusion of the Bagdarin synform, are presumed to be the main source of clastic material. Another source area at that time could be a magmatic arc, as evidenced by the volcanomictic composition of terrigenous clastic rocks and the presence of pyroclastic rocks. The sedimentary complexes of the Tocher formation were formed in a deepening basin adjacent to the volcanic zone. Sedimentation took place in conditions of the continental slope and its foot, against the background of the growth of paleobasin-border uplifts. These conclusions are in agreement with the previous ideas that the Tocher formation accumulated in the geodynamic environment of an active Andean-type continental margin, concurrently to the formation of the Kydzhimite supra-subduction volcanic zone and the Tocher rear trough-fill graywacke turbidite system at the end of the Late Devonian-beginning of the Early Carboniferous between the Siberian Continent and the Mongol-Okhotsk Ocean.

The task was set on investigation of the possibility of constructing a new algorithm for earthquake prediction based on a set of precursor effects that had been reliably identified from the world data as a result of constructing the generalized vicinity of a strong earthquake from a scaled combination of the data on a large number of foreshock and aftershock areas of individual strong earthquakes. In relation to the Kamchatka-Northern Kurils region, the first-stage solution of this task lies in clarification of the regional character of the averaged precursor effects on the basis of the most complete and homogeneous regional catalogue. There has been a later onset of anomalous changes in the intensity of flow of events and in the slope of the recurrence diagram for intermediate-depth earthquakes. The deep-seated earthquakes show a dominant trend of increased rather than decreased depth of weak events in the vicinity of strong events. The specified features of the averaged precursor behavior will be used as typical patterns to predict different-depth earthquakes in the Kuril-Kamchatka region.

The study deals with the analysis of the evolution of seismicity and inner crustal movements in Taiwan over the past 10 years. The primary data sources included time series generated from permanent GPS observations, the earthquake catalog, and the location of the main tectonic structures. Horizontal displacement vectors of GPS stations were determined for each day, relative to the initial epoch. An inner reference system was used in the absence of general area motion defined in the global coordinate system. An animation video was made for synoptic analysis of the evolution of internally generated seismic and tectonic motions. It is shown that the majority of strong M≥6 earthquakes occurred within the boundaries of the inner crustal movement deficit zones or thereon. This allows us to consider such highstrength crustal areas as prognostic signs of earthquakes. They are revealed by GPS observations over several years and destroyed by strong seismic events, as well as by large groups of moderate and weak earthquakes. By 2024, on the island there was formed an east-to-west elongated high-strength zone. It connects the place of convergence of the Ryukyu and Manila trenches with the insular land. It can be assumed that this area marks a zone of high seismic-generating stresses, which is important to take into account in further assessment of seismic hazard.

The aim of this study is to quantify and map a recent seismic swarm sequence that occurred in the Alboran Sea between 2020 and 2021, focusing specifically on the South Alboran Basin. To identify the seismic clusters, a criterion based on seismicity is employed, considering the distribution of two parameters: the kernel density of earthquakes and the kernel density of seismic moments. The first parameter reveals the presence of two seismic clusters: one located north of Al Hoceima, specifically within the southern segment of the Al-Idrissi Fault System (AIFS), and another in the Granada Basin. The second parameter indicates that both clusters released significant amounts of energy, particularly in the southern part of the AIFS, with values reaching up to 1.6·10¹⁴ J·km^–2·year^–1. The 3D seismic modeling indicates a clustering of seismic occurrences in northern Morocco, displaying an eastward pattern in terms of depth. This observation leads to speculation about the existence of nearby geological formations, possibly associated with the AIFS system. Analysis according to the Gutenberg-Richter law shows that the seismic swarm sequence in the southern Alboran Basin exhibits a b-value close to 1, indicating a slip regime. Temporal analysis of the b-value variation reveals two stress regimes: an initial decreasing regime with a b-value close to one, succeeded by a sharp increase indicative of an extensional regime, possibly due to fracture opening. The focal mechanisms show an alternation between strikeslip and strike-slip with normal components, indicative of a transtensional regime. This type of faulting suggests both lateral motion and some degree of extensional force, which aligns with certain rises in the b-value, as these could correspond to stress release events associated with opening fractures or fault segments, although the timing does not perfectly match b-value fluctuations. Together, these findings highlight a complex tectonic environment marked by strike-slip and transtensional forces, supporting the ongoing southern development of the AIFS.

This study presents a comprehensive investigation of the crustal structure in Thailand, Myanmar, and Malaysia using Rayleigh wave dispersion data from a dense network of 49 seismic stations. A direct inversion approach is employed to derive a high-resolution, 3D shear wave velocity model of the crust, circumventing the traditional intermediate step of constructing group velocity maps. The Fast Marching Method is utilized to compute surface wave travel times and ray paths, ensuring an accurate representation of the complex wave propagation patterns within the heterogeneous Earth structure. The resulting 3D velocity model, with dimensions of 120 (longitude) × 112 (latitude) × 9 (depth) and a total of 120960 grid points, reveals significant lateral heterogeneity that correlates with major tectonic features such as the West Burma terrane, Shan-Thai terrane, Indo-China terrane, and the Sagaing fault. The integration of these findings with existing geological and geophysical knowledge provides critical insights into the tectonic evolution and crustal dynamics of this seismically active region, furthering our understanding of the complex interplay between tectonic processes and crustal architecture in Southeast Asia.

The 3D model of tectonic fragmentation of the block of rock for the central part of Iturup Island has been developed to clarify the permeable zones of the upper part of the Earth’s crust. The use of the thermal infrared cameras allows us to image the bottom of Lake Utinaya Banya. The differential-leveling survey data helped us to develop the 3D model of the relief of the lake basin and the adjacent areas. We made chemical analyzes of waters and free gases released from the bottom of Lake Utinaya Banya. We revealed mineral composition of sediments collected during drilling in the area of the explosive event on the lake. Also we presented the conceptual model of the hydrothermal-magmatic system of the studied area. Thus, the obtained data suggest that Lake Utinaya Banya, located in the central part of Iturup Island may have been formed as the result of a series of hydrothermal eruptions. So, we can conclude that there is a risk of new hydrothermal explosions at Lake Utinaya Banya in the future.