Karaganda Coal Basin
Karaganda Coal Basin
one of the major hard coal basins of the USSR, the third most important source of coal after the Donets and Kuznetsk basins. It is located in Karaganda Oblast, Kazakh SSR. The area of the basin is 3, 600 sq km, with a length (from west to east) of 120 km and a width of 30–50 km. The Karaganda Coal Basin is situated in the Kazakh Melkosopochnik.
Coal was discovered in the Karaganda Basin in the middle of the 19th century. At that time primitive coal mining was started to supply the nearby Spasskii Zavod copper smelting plant. The first operational and exploratory shaft mines were sunk in 1930–31. Geological prospecting in the basin developed extensively during the Great Patriotic War (1941–45) and in the postwar period. By 1954, a complete geological and industrial evaluation of the basin had been made. At the base of a thick (up to 4, 500 m) coal-bearing series of Carboniferous age lie the Terekty strata of the Lower Visean, which are represented by green and bluish gray clay shales, tuffites, and limestones. The coal-bearing series is composed of alternating layers of sandstones, siltstones, argillites, coals, and, more rarely, conglomerates, limestones, and tuffs and is divided into suites (see Table 1). Lower and Middle Jurassic coal-bearing deposits with a total thickness of up to 600 m and represented by conglomerates, sandstones, argillites, and coals lie with great disconformity on the denuded surface of Carboniferous coal-bearing series. The Lower and Middle Jurassic coal-bearing deposits are overlain by an Upper Jurassic variegated conglomerate-sandstone-siltstone suite. Paleogene and Neocene deposits are represented by red and green clays and sands. Anthropogene deposits consist of loams, sands, and shingles.
|Table 1. Suites in the Karaganda Coal Basin|
The Karaganda Coal Basin is of the geosynclinal type and forms an asymmetric synclinorium stretching in a latitudinal direction. The northern limb is gentle (10°–30°), while the southern is steep (up to inverted). There are numerous faults, both longitudinal and transverse in relation to the general direction of the folds. The formation of the basin’s geological structure is linked mainly with Hercynian folding. An important role in the creation of the present structure was played by Kimmerian movements, which were expressed in major latitudinal thrusts (reverse faults) of Paleozoic rock onto the Jurassic deposits along the southern edge of the basin.
The presence of coal is mostly related to the sediments of the Carboniferous system.
The thickness of workable seams ranges from 0.7 to 2.5 m, with individual seams reaching 7–8 m. Their structure is very complex. The coals are humic and hard. Approximately one-third of the coking coals are easily concentrated. The remainder, as a consequence of high ash content and difficulty of concentration, are power coals. The coals of the Ashliarik and Tentek suites have a high ash content (20–45 percent), while those of the Karanganda (8–25 percent) and Dolinskoe (4–15 percent) suites have a lower ash content. The coals are low-sulfur (sulfur content rarely exceeds 1 percent). Phosphorus content is 0.01–0.1 percent. The working moisture content is 3–6 percent; the combustion heat of the combustible mass is 29.3–35.6 megajoules per kg (7, 000–8, 500 kilocalories per kg), and the combustion heat of the working fuel is 20.9–25.1 megajoules per kg (5, 000–6, 000 kilocalories per kg). In terms of the degree of metamorphism (taking the volatile matter yield and caking capacity into account), the coals of the basin are classified in the following ranks: gas, fat, fat coking, coking, coking 2, and lean caking coals.
The presence of coal in the Jurassic deposits is related to lacustrine sediments that formed under continental conditions. The established Dubovka and Mikhailovka suites contain more than 15 lenticular coal seams ranging in thickness from lm to 5m (rarely more than 20m). The brown coals (B-3 group) have an ash content of 15–22 percent, a sulfur content of 0.01–1.2, and a volatile matter yield of 42–52 percent of the combustible mass. The working moisture content is 9–19 percent; the tar yield is 9–13 percent; the combustion heat of the combustible mass is 26.0–29.7 megajoules per kg (6, 200–7, 100 kilocalories per kg), and the combustion heat of the working fuel averages 15.2 megajoules per kg (3, 620 kilocalories per kg). The Jurassic coals of the Mikhailovskoe deposit are strip mined. The Kumyskudukskoe deposit is being prepared for working by the open-pit method.
The hard coals are being worked intensively by shaft mines. The total geological coal reserves down to a depth of 1, 800 m have been estimated at 51.3 billion tons; the commercial reserves as of Jan. 1, 1970, were 7.8 billion tons. In 1971 production reached 39.8 million tons. The consumers of the coking coals are the metallurgical plants of Kazakhstan and the Southern Urals, while the power coals are used by railroad transport, power plants, and industrial enterprises.
In addition to coals, the Karaganda Coal Basin has significant reserves of high-quality underground water, refractory clays, building stone, gypsum, sands, limestones, and marls.
The Karaganda Coal Basin is a major industrial region. Aside from the oblast center of Karaganda, new towns, including Sarán’, Abai, and Shakhtinsk, have grown up in the basin. Mining machine building, metallurgy (Temirtau), chemistry, power engineering, and other industrial sectors are also developing.
REFERENCEKushev, G. L. Karagandinskii uglenosnyi bassein [2nd ed.]. Alma-Ata, 1963.
G. L. KUSHEV and A. K. MATVEEV