Structural and petrographic features of K12 coal seam in the Karaganda Basin, and their influence on processing properties

The article describes the integrated geological and petrographic research of the Karaganda Coal Basin. The scope of the analysis embraced the structural tectonics, stratigraphic confinedness of coal-bearing strata and the patterns of the physical layout of productive strata within the limits of the Tentek, Sherubainura, Karaganda and Upper Sokyr industrial regions. The deposition conditions of sediments and the post-sedimentation alterations of organic matter, which condition the actual material constitution and a carbonization degree of coal in the test basin, are analyzed. The details of coal petrology are given, including genetic prerequisites of organic matter formation, classification and quantitative characteristics of macerals, their morphological and diagnostic properties in reflected light, as well as structural and textural features of carbon matter. Micro-lithotypes and petrotypes, reflective of the conditions of pet accumulation, facial environment and transformation degree of an initial plant material are systematized. It is shown how the petrographic characteristics of coals are interconnected with their physical, mechanical and processing properties. Spotlight of the study is on K12 coal seam–the highest productive stratum of the Lower Carboniferous Karaganda series. Based on the microscopic research data and the quality analysis, the material constitution and petrographic constituents, degree of metamorphism, vitrinite reflectance, mineral impurity content and the structure heterogeneity of the test coal type are evaluated. The interrelation of the maceral composition, coking properties, gas content and dressability of coal with the deformation behavior of rock mass is shown. It is highlighted that the petrography heterogeneity of K12 coal is one of the development factors of plastic deformations and floor buckling in mine roadways. The results can be used in geological-engineering and geomechanical modeling, in coal quality prediction and in stability estimation of mine roadways. 

Zamaliyev N. M., Kryazheva T. V., Mussin R. A., Akhmatnurov D. R., Sadchikov A. V. Structural and petrographic features of K12 coal seam in the Karaganda Basin, and their influence on processing properties. MIAB. Mining Inf. Anal. Bull. 2026;(7):109-129. [In Russ]. DOI: 10.25018/0236_1493_2026_7_0_109.

This research was carried out with the support of the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan within the framework of program-targeted financing for the implementation of the scientific and scientific-technical program of the IRN BR28712407.

N.M. Zamaliyev¹, PhD, Acting Associate Professor, e-mail: nailzamaliev@mail.ru, ORCID ID: 0000-0003-0628-2654,
T.V. Kryazheva, Cand. Sci. (Geol. Mineral.), Associate Professor, O.A. Baikonurov Zhezkazgan University, Zhezkazgan, Republic of Kazakhstan, e-mail: kryazheva_t@mail.ru, ORCID ID: 0000-0003-2804-020X,
R.A. Mussin¹, PhD, Acting Associate Professor, e-mail: R.A.Mussin@mail.ru, ORCID ID: 0000-0002-1206-6889,
D.R. Akhmatnurov¹, PhD, Head of Laboratory, e-mail: d.akhmatnurov@gmail.com, ORCID ID: 0000-0001-9485-3669,
A.V. Sadchikov¹, Cand. Sci. (Eng.), Senior Lecturer, e-mail: a.sadchikov@kstu.kz, ORCID ID: 0000-0002-6022-2073,
¹ Abylkas Saginov Karaganda Technical University, Karaganda, 100027, Republic of Kazakhstan.

R.A. Mussin, e-mail: R.A.Mussin@mail.ru.

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