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 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.
Specification of Coal Seams
The Kazakhstanskaya mine has rights to develop the following coal seams: T3, T1, T11, D10, D9, D6, D5, D4, D3, and D1. Seams D6 and D11 are currently being developed, and D10 is being prepared for development. Seam D6 is the thickest and most stable seam of the Dolinskaya suite. Its effective thickness varies from 2.92 to 7.04 m, with an average thickness of 5.44m. The seam has a complex structure where up to 8-10 interlayers of strata of different thicknesses (usually not exceeding 0.2m) are being noted. The most stable is the waste strata interlayer of 0.05-0.20m, appearing in the upper part of the seam. The other strata interlayers are lens-shaped.
Seam D11 is relatively stable and of moderately complex structure. Its effective thickness varies from 0.7 to 1.69m, with an average thickness of 1.13m. Thin strata interlayers of 0.05 0.20m are noted in the upper part of the seam. The seam has a complex, easy-breaking roof, with a thickness of 0.5-0.7m.
Seam D10 is relatively stable and has a complex structure and thickness of 1.14m. The formation interlayer of 0.05-0.30m splits the seam into two banks, with the upper bank being 1.5-2 times larger than the lower one. In terms of continuity of thickness and structure, the coal seams are specified as follows:
• Continuous – D6;
• Relatively continuous – T3, T1, D11, D10, D1;
• Irregular seams – D9, D5, D4, D3.