№ 10 (2024)

The article is devoted to the genesis of microcrystalline dolomites of the Kashira and Podolsk horizons of the Moscow stage, which are oil reservoirs in the western part of Bashkortostan. They form consistent layers of low thickness, traceable for tens of kilometers, which determines the relevance of studying the conditions of dolomite formation. Dolomites are composed of crystals 1–10 μm in size with sulfate inclusions and sepiolite admixture. Sepiolites are developed in the intercrystalline space as the finest threads and films enveloping dolomite crystals. A detailed study of sepiolites with a scanning electron microscope with experiments on partial dissolution of dolomites with acid showed an abundance of bacteriomorphs of sepiolite composition. The distribution of REE and Y in dolomites and host rocks is considered. Good convergence in REE spectra is noted for a number of dolomite samples. As a result of the conducted complex of studies, a conclusion is made about the microbial-induced formation of dolomite and sepiolite in the shallowest part of the sea basin with high salinity.

Mineralogical-analytical methods and methodologies for predictive assessment of solid minerals essentially determine the feasibility and tactics of developing raw materials, and, if necessary, the possibility of replacing, first of all, strategic raw materials with others. Using the example of strategic types of minerals: manganese ores of the Usinsk and bauxite deposits of the Upper Shchugor deposit, the possibilities of mineralogical study of ores with complex composition and structure as part of assessing their quality are considered. The problems and prospects of technological mineralogy in solving problems of mineral resources of strategic metals are identified.

This brief report presents the results of our study of the effect of shungite sample thickness (both shungite rocks and vein forms comparable to higher anthraxolites) on their electrophysical properties. The study was conducted by measuring impedance in the frequency range of 0.05–15 MHz. Shungite samples with a carbon content of 96, 95, 73, and 38 at. % and a thickness ranging from 5 mm to 12–15 μm were studied. A significant increase in resistance was found with a decrease in sample thickness to 100 μm or less. In this case, the inductive resistance typical of shungite macrosamples changes to capacitive resistance or only active resistance appears. Thus, it is shown that not only the total content, but also the form and dimensionality of the occurrence of such carbon affects the electrophysical properties of the rock. The obtained results can be used to interpret electrical exploration data of rocks containing disordered carbon (shungites, anthraxolites) in vein and lenticular form, and also to show new prospects for the use of such carbon in the development of functional materials.

On April 12, 2024, the 16th Russian Seminar on Technological Mineralogy with a thematic program was held at the Institute of Geology, Komi SC UB RAS. A plenary report «Role of the RMS Technological Mineralogy Commission in improving the completeness and integrity of mineral raw material utilization» was presented. V. V. Shchiptsov with co-authors O. B. Kotova and E. G. Ozhogina presented their analysis of the scientific, organizational and practical activities of the Technological Mineralogy Commission of the Russian Mineralogical Society from the moment of its creation by the decision of the 6th All-Union Congress of the Mineralogical Society in December 1982 to the present day. The role of the Commission in conducting geological, mineralogical and technological research related to the technological assessment of mineral raw materials and the promotion of technological mineralogy as an important independent scientific direction of the Earth Sciences at various scientific sites and publications is shown.