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The present study investigates changes occurring in the material composition and properties of the South Yakutian carbonate soils during cryogenesis. The nature of the transformations of certain limestone varieties composing the surfaces of rock massifs was determined using scanning electron microscopy, 3D X-ray tomography, as well as lithological–mineralogical and optical–petrographic studies, over a 10-year period. The areas in carbonate rock massifs with increased clay content, pyritisation, dolomitisation, and baritisation, as well as zones of calcite and dolomite junction, were found to be least resistant to the effects of processes associated with water phase transitions, i.e., freezing and thawing. The mineral proportion of limestone on the surface of soil massifs chemically processed over a 10-year period reached 5–7% of the volume of the weathered rocks. In the process of transformation, not only the composition of the rocks changed, but also the nature of the structural bonds that significantly influence their mechanical strength properties. The number of cracks for weathered soil samples increased by 9–16%; their opening increased by 13–18%. For rocks initially having uniaxial compression strength in the range of 33–46 MPa, this strength was reduced by 19–27%. Laboratory experiments on 1000-fold cyclic freezing and thawing of carbonate rock samples (which corresponds to an 8–10-year period of weathering on the surface of a mountain outcrop under the natural conditions of South Yakutia) demonstrate the similarity of these changes with those observed in samples taken from the sides of open pits 10 years ago. In general, soils are influenced by a wide range of environmental factors under natural conditions. The significant influence of alternating temperatures on the changes in the composition and structure of limestones in South Yakutia is characterised in detail.

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This article highlights key moments in the history of the development of loose material micromorphological analysis, analysing its current position in the context of lithological facies studies. This method was developed to reconstruct the conditions of transport and deposition of Quaternary deposits. Since the 1970s, the study of grain surfaces has been used to study the features of cryogenesis formation in deposits. The development of the method was facilitated by the technical progress of the twentieth century, and the development of electron microscopy has brought the method to a completely new level. Currently, micromorphological analysis remains the most widely used method of analysing the surface of grains. However, modern methods for studying the surface of particles, such as computed tomography, are now being introduced into the research methodology. This in turn significantly expands the research scope: in recent years, the shape and degree of roundness of grains has been used to analyse the properties of soils for construction. As of today, the volume of publications abroad significantly exceeds the number of publications in Russia.