In December 2023, ArcelorMittal (former wholly-owner of the Karaganda Coal Mines Complex which includes Tentekskaya mine) completed the sale of its assets in Kazakhstan to Qazaqstan Investment Corporation (QIC). QIC acquired all the shares in ArcelorMittal Temirtau and ArcelorMittal Tubular Products Aktau. Qazaqstan Steel Group and its founder Andrey Lavrentiev became the new investor. ArcelorMittal Temirtau was later renamed Qarmet.
Summary:
The coal mines of Qarmet JSC (former ArcelorMittal Temirtau) are located in the Karaganda Coal Basin. The basin is more than 3,000 square kilometers and was formed by strata of Upper Devonian and Carbonic ages, Mesozoic and Cainozoic formations. Due to structural peculiarities, the coal basin is divided into three geology-based mining areas: Karagandinskiy, Sherubay-Nurinskiy and Tentekskiy.
Karaganda basin is located on the area of the same name and in the center of this region. Carbon coal-content area occupies the land of about 2000 km2 at the total thickness 4000m. Four synclines are notable in the basin: Tentek, Sherubainur, Karaganda and Verkhnesokursk, first three of them make an industrial part of basin and are studied full enough up to the depths of 700-1300m.
Productive sediments are represented by Ashlyarik, Karaganda, Dolinsk and Tentek series which contain up to 30 coal seams with the total working thickness 40m, coal ash content varies within the limits of 10-35 % with the tendency of reduction upwards the section. The most-widely spread are coals of types from hvBb to mvb. Karaganda basin is considered as a high gas content and gas content seams intensively grow from the beginning of methane zone up to 400-500m reaching 15-20 m3/t, and are more stabilized on the depth within the limits of 22-27 m3/t. Gas weathering zone depth varies within the limits of 60-250 m.
Tentekskaya Mine
Technical borders of the mine include the following 10 working coal seams: T3, T1, D11, D10, D9, D7, D6, D5, D4, D1.
Geological structure of the mine field is represented by sedimentations of over-karaganda, dolinskaya, and tentekskaya suites of carbonic age, overlaid by neogene, paleogene, and quaternary sedimentations of overall thickness from 7 to 86 m.
Over-karaganda suite is represented by argillites, siltstones, fine-grained sandstones, and lenses of coal interlayers.
Dolinskaya suite of overall thickness 520-550m is composed of argillites, siltstones, sandstones and coal seams D1-D11.
Coal seams and coal-bearing strata extend to the west with a 10°-20° angle. Slope angles in the central part of monoclinal increase up to 30°, and at the Northern part, up to 40°-50°.
The field of the mine is complicated by a significant number of disjunctive faults and plicative folding and limited by the big Churubai-Nurinskiy fault.
The Tentekskaya mine is considered dangerous with spontaneous coal and gas outbursts. Coal seams T1 and D6 (south, center) are dangerous at a depth of 350 m and seam D6 (north) – at a depth of 230 m.
The mine is noted for danger from dust.
Coals of the seam D6 are noted for spontaneous combustions.
The seam D6 is a subject to fire risk.