The material composition of potassium and potassium-magnesium salts of the Upper Pechora salt-bearing basin was studied, their lithological variability was established over the area of productive strata, depending on the tectonic features of the foundation. The main mining and geological conditions that complicate the possibility of their extraction and the environmental conditions for organizing mining and processing production of mineral salts were established. The basic physical and technological properties of sylvinite and carnallite rocks mined by the mine method were studied for their enrichment by halurgical and flotation methods. The objectives of the work were: determining the material composition, studying textural and structural features and assessing the technological processing of potassium rocks in the Upper Pechora salt-bearing basin. When solving the problems, the following methods were used: a study of the textural and structural features of sylvinites using the petrographic method; the chemical composition of samples and solutions was analyzed by AES spectrometry; the mineral composition of the water-insoluble residue is determined by X-ray quantitative phase analysis.

A complex comparative study of diamonds from commercially productive diatremes of DaldynAlakitsky field (Udachnaya, Zarnitsa) determined mineral typomorphic features, which allows diagnosing dispersion haloes of kimberlite material in sedimentary thick layers. By the set of typomorphic features, diamonds from Udachnaya pipe have many common features with crystals of other deposits of Daldyn-Alakitsky diamondiferous region. Increased content of variety II and III cubes, close by their features to diamonds from deep inclusions of eclogites, may be referred as inherent only to the Udachnaya pipe features. Zarnitsa pipe demonstarted pronounced prevalence of rhombic dodecahedral habit crystals of variety 1 with large concentration (> 30 %) of typically rounded diamonds. On the whole, diamonds of Daldyn field are characterized by a complex of typomorphic features, which allow distinguishing them from diatremes of other diamondiferous regions of the Siberian platform with confidence.

The purpose of the study is to investigate the cranes from loess-like deposits as indicator formations for the glacial epochs of the late Pleistocene – Holocene using current lithology methods. The motivating reason for the study was that loess-like deposits directly “seal” the industrial placer of the Silurian diamond-bearing reservoir in the Vishera diamondiferous region.

Loess doll (loess pupae, dutiki) are concretions weakly cemented by iron hydroxides, consisting of quartz grains with an admixture of fine-silty feldspars. In terms of granulometry and mineral composition, the cranes correspond to the loess-like deposits that host them and are the frame of the root system of tundra-type grass vegetation. In the center of the concretion, in place of the disappeared grass root, a hollow tubule is preserved, sometimes filled with silty sand from the surrounding rocks.

The granulometric composition of loess-like deposits was studied using an Analysette 22 MicroTec plus laser diffraction analyzer. Mineral composition of the heavy fraction of loess-like and underlying sediments – using quantitative mineralogical analysis. Quantitative gross mineral composition and the ratio of clay minerals in the pelitic fraction – using a D2 Phaser X-ray powder diffractometer (Bruker, Germany).

The data obtained can be used for geological surveying and exploration of diamond-bearing placers in the Urals and in regions with a similar geological structure. It must be borne in mind that in the study area the described loess-like deposits do not have a direct connection with industrial placer diamond content.

The article presents the results of the study by various geologists of the geological structure and prospects of ore-bearing trog complexes performing structures such as throgs, which were identified at different stages of geological research in the western part of the Aldan-Stanovy shield. The main types of traction complexes and their sections were determined. The nature of the occurrence of sedimentary (terrigenous), volcanogenicsedimentary and metavolcanic rocks performing throgs and forming throg complexes was established. The nature of the ratio of these rocks in the context of the trog complex in the studied trogs was described. The results of the study of trog complexes showed that they are generally characterized by facies variability, heterogeneity of metamorphism and dynamothermal processing of rocks (especially in the sides of trogs) with the formation of mylonites and cataclasites. It was established that the throgs are confined to three regional systems of discontinuous disturbances. Both consonantal and secant discontinuities were marked inside the throgs, defining their block tectonics. The results of determining the geological age of the rocks of the trogovoi complex were presented. The trog structures are characterized by ore mineralization associated with the processes of sedimentation (ferruginous quartzites, copper sandstones) and volcanogenic ore formation (copper-crusted and polymetallic mineralization), as well as with the processes of metamorphogenic-hydrothermal redistribution of ore matter (stratiform scheelite mineralization, ore-bearing quartz veins). It was also found that the metallogeny of the trog structures has not been studied sufficiently. Nevertheless, the majority of geologists who studied the trogovye complexes noted in their reports that Precambrian trogovye complexes can be considered as important and metallogenically promising geological objects in the western part of the Aldan-Stanovy Shield and deserve more in-depth study.

The article provides the material on the geological structure, structures, tectonic position and metamorphism of rocks developed within the Chara-Tokko iron ore region, identified in the western part of the Aldan-Stanovoy shield. Most researchers agree that the Chara-Tokko iron ore region is confined to a trough that formed on the site of one of the long-lived deep fault zones of meridional strike. This zone received various names (Derbegelakhskaya, Charo-Imalykskaya, Tarynakhskaya, etc.). Currently, the fault zone and the trough trough are called Chara-Tokko after the name of the iron ore region. It is assumed that to the south, the iron ore deposits of the Chara group (Sulumatskoye, Nizhne-Sakukanskoye) are confined to the continuation of this trough trough. The nature and conditions of metamorphism can be judged by the mineral associations of some rocks of the sedimentary productive complex, such as metapelites or ferruginous quartzites. It is noted that metapelites, now represented by gneisses and mica schists with high-alumina minerals, are especially important for this. Based on their characteristic mineral associations, three temperature facies were identified in the Chara-Tokko iron ore region: staurolite, biotite-muscovite gneiss and orthoclase-biotite-sillimanite. The internal structure of the Chara-Tokko iron ore field were not sufficiently studied and is extremely controversial. The boundaries of metamorphic zones are mainly parallel to the general strike of the structures and only in rare cases intersect the stripes of productive sedimentary units. After the temperature maximum of progressive metamorphism and past granitization, a significant period of cooling began, which was heated and in some places impregnated with layer-by-layer injections of migmatites and bodies of granites of the Borsala sequence. Gradual cooling was accompanied by regressive metamorphism with the formation of low-temperature minerals at the expense of higher-temperature ones. It is believed that ferruginous quartzites of the western part of the Aldan-Stanovoi shield are part of sedimentary-volcanogenic rock complexes that fill suture troughs or troughs confined to long-lived deep fault zones. The processes of regressive metamorphism manifested themselves most intensively in tectonic zones. The nature of the processes depends on the composition of the host rocks. The regressive phenomena of continuous chloritization and epidotization are associated with the local movement of components, mainly calcium.

The article presents the results of a study of the mineral composition, structural and textural features of sediments of the Ustchurochinskaya and Churochinskaya formations in the Krasnovisherskiy diamondiferous region. Rocks were studied with the petrographic analysis. According to the results of petrographic study, the composition of rocks of the Ustchurochinskaya and Churochinskaya formations was clarified. The rocks of the Ustchurochinsky formation were represented by siltstones, sandstones and gravelly sandstones. The rocks of the Churochinskaya formation are represented by tillite with interlayers of siltstones. The roof is represented micrograined dense dolomites. A detailed study of rock fragments of different genesis gives an idea of the sources. The Vendian deposits consist of erosion products of the underlying sediments of the Upper Riphean formations, volcanic rocks, granitoids and gneisses, the source of which are the Timan uplifts with outcrops of crystalline basement rocks of the Russkaja Plate.

Тhe results of generalization and GIS integration of the results of the study of all known indigenous deposits and manifestations of diamonds located in the distributed and undistributed fund of the subsoil of the Russian Federation are presented. The work takes into account the results of prospecting, exploration and exploitation works, minutes of meetings of regional (TKZ) and federal (RKZ and GKZ) commissions on mineral reserves and published data. As a result, a GIS-integrated database was created containing 1,319 objects, for each of which key parameters were determined: coordinates, shape, size, age, average diamond content, forecast resources, and diamond reserves. It was established that the indigenous diamond deposits are concentrated in the Central Siberian subprovincia and account for 2.3 % of all known kimberlite bodies, diamond-bearing kimberlite bodies in the Yakut diamond-bearing province – 282, the predominant body shape is a pipe (59 %). There is no correlation between the size of kimberlite bodies and their diamond content, small pipes, as well as large diatremes, can be industrially diamondiferous, the prevailing absolute age of industrially diamondiferous kimberlites is 329-382 million years.

In this article we present the results of landscape structure study in the Middle Lena valley (Erkeni, Ensieli and Tuimaada), made using GIS mapping based on Sentinel 2 satellite images and ASTER GDEM datasets. Alas complexes and croplands were identified using K-means image segmentation with different initial numbers. Three machine learning algorithms were tested for pixel-based land cover classification. The best result was achieved with the Support Vector Machine classifier. The mapping revealed the landscape structure of 20 spatial units, which were organized into groups of upland, alas, slope, valley and floodplain landscapes. The contrasting landscape structure of the Middle Lena valley was revealed. The northern Ensieli valley is characterized by the predominance of forest larch-pine landscapes, alas complexes mostly dry with steppe meadows are widespread in the watershed. The slopes are dominated by larch forests with patches of birch. The central Tuimaada valley is the most anthropogenically transformed, here steppe meadows and anthropogenic steppes dominate. The plateau part is mainly forested with croplands. The southern valley of the Erkeni is characterized by the smallest area of the valley part dominated by steppe meadows, the slopes of the main bank of the southern and south-eastern exposition are covered with xerophytic meadows. The landscape structure of valleys, floodplain and plakor parts largely determines the specifics of agricultural land use of the local population. The results obtained can be used for further research into the response of permafrost landscapes of the Middle Lena valleys to increased anthropogenic pressure in the context of climate change.

The article reveals the activities of the Zolotinka geocryological station in South Yakutia, one of the BAM expeditions of the Institute of Permafrost, USSR Academy of Sciences. Relevance. The article is dedicated to the 95th anniversary of the birth of Maria Gavrilova, a climatologist, permafrost scientist, famous in Russian and world science, Doctor of Geographical Sciences, professor, Honored Scientist of the Russian Federation and the Republic of Sakha (Yakutia), academician of the Academy of Sciences of the Republic of Sakha (Yakutia), the Russian Academy of Natural Sciences [1].

The BAM expeditions of the Institute of Permafrost were united by a common research topic “Prediction of the evolution of the cryolithozone in the development of the territory adjacent to the BAM railway” to predict the state of geocryological conditions and make practical recommendations for the construction of engineering structures in settlements, stations and roads in the Maly BAM zone [2].

In different natural conditions, landscapes of the foothills of the Stanovoi Ridge of South Yakutia (valleys, watersheds, as well as on the slopes of different exposures), special permafrost conditions are formed associated with the patterns of heat exchange of the upper layers of the earth’s crust – the earth’s surface – the atmosphere [2]. To identify permafrost, microclimatic and thermal balance conditions in the midlands of South Yakutia, on the territory of the village of Iengra of the Neryungrinsky City Council, on September 1, 1975, the Zolotinka geocryological station was organized under the leadership of Dr. Gavrilova. The year-round station conducted three full cycles of microclimatic and thermal balance studies from 1975-1978. A retrospective approach to the topic of the BAM expedition organized by the Institute of Permafrost made it possible in this article to familiarize and summarize in detail the scientific and organizational activities of Maria Gavrilova on the work of the Zolotinka geocryological station in 1975-1978.