pdf № 371, November

DOI: 10.19110/geov.2025.11.1

Granites recovered by boreholes 1-Yuzhnaya Bolotnaya and 1-Sosyanskaya in the Izhma zone of the Timan megablock of the Pechora basin basement are most similar in their mineral and chemical composition to S-type granites. U-Pb (SIMS SHRIMP-IIe and SHRIMP-RG) zircon studies of these granitoids have not allowed for a correct determination of the rock formation time, as the zircons are either inherited or highly discordant. The granite age has been revised by the ⁴⁰Ar-³⁹Ar dating of muscovite from the same samples. The ⁴⁰Ar-³⁹Ar age of muscovite in granites of the 1-Yuzhnaya Bolotnaya borehole is 548 ± 7 Ma and in the 1-Sosyanskaya borehole is 565 ± 7 Ma. These data correlate with U-Pb (SIMS SHRIMP-IIe and SHRIMP-RG) ages on zircons from granites of other zones of Pechora basin basement and confirms the large-scale intrusion of granitoids in the Late Vendian during collision processes at the final stage of Timanian tectogenesis.

Keywords: Pechora basin, Izhma zone, basement, granite, zircon, U-Pb SHRIMP-RG age, muscovite, ⁴⁰Ar-³⁹Ar age of muscovite

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DOI: 10.19110/geov.2025.11.2

For the first time, original data from the Tunantza deposit, located in the Cordillera del Cóndor in the Sub-Andean zone of southeastern Ecuador, are presented. The study includes a geological map, descriptions of host rocks and mineralized structures, which serve as the basis for the preliminary classification of the deposit and understanding its origin. Geological materials and documentation from surface outcrops and underground workings at the Tunantza deposit are used; the petrographic study involves the analysis of 96 thin sections. Literature data on similar deposits are used. Important characteristics of the deposit and similar objects are obtained. A classification of these deposits based on the position of mineralization relative to the pipe is proposed. The results demonstrate the relationship between the deposit and the type of mineralized structures and should be used as a tool in the exploration and classification of epithermal and porphyry deposits.

Keywords: breccia-pipe, classification, gold, epithermal, Cordillera del Condor

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DOI: 10.19110/geov.2025.11.3

For the first time, lithological mapping has been carried out for the Shchuchinsky zone of the Polar Urals using the space decoding method on the basis of digital data from the Harmonized Landsat Sentinel-2 remote sensing instrument. The objective of this study is to evaluate the feasibility and effectiveness of Harmonized Landsat Sentinel-2 satellite data with modern image processing methods for lithological mapping of the northeastern slope of the Polar Urals (the Shchuchinsk zone hosting the Yunyaginskoye Au-Fe deposit).

We have created a lithological map of the study area showing a strong correlation with the existing geological map of the region. Specifically, metamorphosed rocks are reliably identified by dark blue to violet hues, ultramafic rocks by red, and a combination of green and blue indicates areas of sedimentary and metamorphic rocks.

The study results confirm the effectiveness of the chosen approach and demonstrate a significant potential of using this satellite imagery for geological mapping in high-mountain terrain with a thin cover of Quaternary sediments (up to 6 m). To further improve the accuracy and expand the method applicability, integration with other satellite image processing techniques that effectively identify lithological units under thicker Quaternary cover is recommended together with fieldwork verification.

Keywords: satellite imagery, the Polar Urals, Harmonized Landsat Sentinel-2 (HLS), lithological mapping, minimal noise, color composite

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DOI: 10.19110/geov.2025.11.4

We conducted shallow seismic exploration in the Middle Timan region to study the depth and spatial distribution of geological bodies. The study focused on the «Verkhnemezenskaya» kimberlite pipe, and the «Pavyuga» and «Kamenskaya» magnetic anomalies, located within the southern part of the Chetlas uplift.

Analysis of the seismograms revealed distinct anomalies in the form of changes in first-arrival waveforms, loss of correlation, and reduced seismic wave intensity. These features clearly delineated the «Verkhnemezenskaya» pipe, and the «Pavyuga» magnetic anomaly zone.

The shallow seismic survey proved effective in mapping geological boundaries based on vertical heterogeneities. The investigation depth, determined by the energy of the seismic source and the spread length (235 m in this case), typically did not exceed 30–50 m., and in the vast majority of cases did not exceed 30—50 m with an alignment of 235 m.

The use of shallow seismic exploration (refraction method) supported this method to identify the boundaries of geological structures based on the heterogeneities of the environment.

Keywords: shallow seismic exploration, linear seismic station, seismograms, velocity section, seismic waves, Middle Timan

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DOI: 10.19110/geov.2025.11.5

Phase composition of kaolin (kaolinite clays, Middle Timan, Russia) has been studied. A method for synthesizing zeolites from low-grade aluminosilicate raw material — kaolinite clay (Middle Timan, Russia) — is adapted. The resulting zeolite sorbents are analyzed by a range of modern analytical methods, and their porous structure parameters are determined. We have found that hydrothermal treatment in an alkaline solution resulted in the formation of two types of zeolites: LTA and FAU (faujasite), both with a high degree of crystallinity. The sorption capacity for Sr²⁺ ions is 180 mg/g, exceeding the values for known micro- and mesoporous sorbents. We have shown that the morphological and structural properties of the zeolite influence its sorption capacity. The resulting zeolites represent an effective and affordable material for use in environmental technologies.

Keywords: kaolinite clay, low-grade aluminosilicate raw material, zeolites, LTA, FAU, faujasite

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DOI: 10.19110/geov.2025.11.6

This article presents the results of developing the «Paleozoic Miospores» relational database and its application to systematizing and analyzing data on Devonian spores. The database contains detailed morphological descriptions, stratigraphic, and geographic references for 190 genera and 1,880 myospore species. The taxonomic nomenclature was standardized according to M. V. Oshurkova (Oshurkova, 2003). The use of digital tools confirmed the previously established dynamics of changes in spore species diversity in the Devonian. The practical significance of this study lies in the creation of a verified digital resource that can be used to solve stratigraphic problems, perform paleoecological, geographic, and climatic reconstructions, and for educational purposes. Future plans include supplementing the database with spore images, which will enable the implementation of a visual search for similar spores based on image comparison using computer vision methods.

Keywords: database, miospores, systematics, Devonian period

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