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We studied the distribution of gold, silver, and platinum group elements (Pd, Pt, Rh, Ir, and Ru) in two bottom sediment cores of the southern Chukchi Sea. It is shown that the Holocene pelite-silty sediments with an age of up to 4.0 ka BP are significantly enriched in these elements, except for Ru and Rh, relative to their clarkes. Native silver minerals were found in all samples by probe microanalysis, whereas gold minerals were revealed only in the surface layer of the sediment core closest to the Chukchi Sea coast. Multicomponent statistical analysis of the chemical composition and grain size of the sediments and the content of organic matter in them has led to the conclusion about the accumulation of clastogenic and chemogenic forms of precious metals. The abnormally high content of gold (0.3 ppm) in the recent sediments near the Chukchi Peninsula coast might be due to its additional removal from the continent as a result of the placer mining there.

Based on integrated structural and geophysical studies and generalization of geophysical, hydrogeological, mineralogical, geochemical and other data, it is shown that the southern cluster of thermal fields of the Kambalny volcanic ridge (South Kamchatka) is included in the modern hydrothermal system. New data on the structure of the steam hydrotherm discharge area investigated to a depth of about 300 m have been obtained. The structural and hydrodynamic connection between two thermal fields from this group has been established. The Kambalny ridge geothermal system embracing all major clusters of thermal fields is assumed to have a single deep-seated source of heat supply.

Surface waves are the main source of coherent noise in land seismic survey, and their suppression is one of the main stages of common depth point data processing designed to improve the quality of tracking primary reflections on time sections. In practice, noise reduction is carried out using procedures from modern software based on numerical modeling of waveforms. However, they are too resource-intensive and have a large number of subjectively customizable parameters. The known algorithms have a common drawback: either the energy of reflected waves is distorted in an interference zone with a noise wave or the noise suppression quality is unsatisfactory. The current research is aimed at improving the filtering algorithm in a time-frequency domain using the slant Karhunen-Loeve transform in order to overcome these limitations, to increase the accuracy and rate of its software implementation, and also to test it when processing profile field data from land-based 2D seismic surveys. The algorithm is modified by developing a new method for determining static corrections for surface wave hodograph rectification in a time-frequency domain and by the application of preprocessing in which the reflected wave signal is removed preliminarily. These and other modifications ensure faster calculations and improve the quality of surface wave interference suppression. In addition, the slant Karhunen-Loeve transform is accelerated by parallelizing calculations across logical processor cores. In this paper, the algorithm is described in detail, its significant advantage over the standard methods of bandpass filtering and f-k filtering is shown, and the results of processing the field data obtained by the SWANA procedure (Geovation 2.0) and by the slant Karhunen-Loeve transform. The result obtained by the slant Karhunen-Loeve transform is superior to the SWANA procedure in terms of the surface wave filtering quality and has only four adjustable parameters (SWANA has 20 parameters).

The paper discusses the results of the development of a deep learning-based algorithm of the inverse Sumudu transform applied to the problem of on-ground non-stationary electromagnetic sounding. The Sumudu transform has potential for solving forward geoelectric problems in three-dimensional earth models because, unlike using the Laplace or Fourier transform, the Sumudu image of a real function is also a real function. Thus, there is no need to use complex numbers in subsequent calculations, which reduces computational costs and memory requirements in case of successful determination of the Sumudu image of the function. The disadvantages of the approach include the absence of an explicit method for calculating the inverse transform. The inversion can be done by solving the corresponding Fredholm integral equation of the first kind, but this is a poorly conditioned task leading to high requirements for the accuracy of the Sumudu image. The use of modern machine learning techniques can provide a method that is more robust to noise in the input data. This paper describes the process of creating a training dataset and developing a neural network algorithm; we evaluate the accuracy and performance of the obtained solution. The proposed method can contribute to the development of new approaches to physical processes modeling as well as to analysis, processing and interpretation of measured geophysical data.

An increase in technogenic impact and the need to conserve biodiversity has set us the task of assessing the baseline biodiversity in mining areas. The aim of this work is to investigate the state of mesofauna of invertebrate animals in the litter and topsoil of typical biotopes of the Middle and Southern taiga. This study is the first in the Perm Krai. The vegetation characteristics of the survey sites are based on field geobotanical descriptions, soil sampling method was used to collect invertebrates, and soil properties were studied using conventional methods. Taxonomic diversity and population structure of soil invertebrates was evaluated, vegetation was described, morphological and physical-chemical analysis of soils as well as correlation analysis of quantitative indicators of soil mesofauna with chemical properties of soils of surveyed sites was performed for the first time on 10 survey sites. All surveyed biotopes have typical for the Ural taiga zone floristic composition and fauna of litter and soil invertebrates. At the same time, vegetation synanthropization is pronounced in all studied forest and meadow phytocenoses. The composition, structure and abundance of invertebrate mesofauna in all studied biotopes depend on the phytocenosis type, litter composition and thickness, the degree of soil and litter moisture. Correlation analysis revealed a relationship between soil acidity level and quantitative indicators of Lumbricidae and Oniscidea. The natural communities studied are affected by anthropogenic factors such as land reclamation, changes in soil composition and structure caused by mechanical disturbances during road construction, etc.

Based on long-term research (1993-2022), the content of chemical elements (Na, K, Ca, Cu, Zn, Fe, Pb, Sr, Zr, Cd, Ni, Co, Cr, Ba, Cd, and Mn) has been determined in 17 plant species of the northern West Siberia region. The regional geochemical background of dominant plant species has been established, and an assessment of changes in the chemical composition of plants in the area of oil and gas condensate field development in the northern West Siberia region has been provided. Indicator species reflecting early trends in ecosystem transformation under the influence of anthropogenic load and associations of chemical elements linked to various sources of pollution have been recommended. The role of phytoindication methods has been demonstrated in detecting subtle changes in the environmental state in the conditions of gas condensate field sites.

The article examines the situation around differential equations as a tool of natural science. On the one hand, during the “Quiet Scientific Revolution” of the 18th century, they made it possible to overcome the limitations of human intuition and reveal the potential of analytical methods for understanding nature. On the other hand, by the end of the 19th century, the problem of integrability of differential equations, which most clearly manifested itself with regard to the “n-body problem,” showed the need to rehabilitate intuition as the most important factor in scientific knowledge. It was the appeal to intuition that determined the creation of qualitative/geometric methods for studying nonlinear systems. Based on the analysis of this situation, the article draws a conclusion about the changes in methodology when scientific knowledge meets its limits: here the choice of mathematical tools is made in such a way that the “complexity” of one of the elements of the research situation, which has become an insurmountable barrier for knowledge, is transferred to some other element. So, this “complexity conversion” allows progress in the study of nature.

The paper reviews «The Inessential Indexical. On the Philosophical Insignificance of Perspective and the First Person» written by Herman Cappelen and Josh Dever. The review presents the main arguments of each of ten chapters

In the monograph "Geological cognition as a subject of philosophical and methodological analysis" (Ekaterinburg, 2003. 200 p.) V.A. Mironov makes an attempt to solve the problem of scientific status of geological cognition. This work is particularly important in the context of the vacuum in the philosophical and methodological studies of geology, which was formed by the end of the 1980s. The author distinguishes two directions, within the framework of which philosophical problems of geology are studied: domestic (Soviet, Russian) and represented in the English-language literature (mainly British and American). At the same time, he draws attention to the fact that separately each of these traditions does not allow to fully reflect the complexity of the process of geological cognition.