Kansk-Achinsk Coal Basin

a basin located in the southern part of Krasnoiarsk Krai, in Kemerovo and Irkutsk oblasts, RSFSR.

The Kansk-Achinsk Coal Basin extends along the Siberian railroad from the Itat station in the west to the Taishet station in the east, a distance of approximately 700 km; it ranges in width from 50 to 250 km. The area of the exposed part of the basin is approximately 45, 000 sq km. The Enisei divides the Kansk-Achinsk Coal Basin into two parts: the western, formerly called the Chulym-Enisei basin, and the eastern, formerly the Kansk basin. Geological coal reserves total 601 billion tons (to a depth of 600 m, according to calculations in 1968), including 140 billion tons suitable for open-pit mining.

The coal-bearing potential of the area was first noticed in the late 19th and early 20th century during geological studies along the route of the Siberian railroad, which was then under construction. Coal mining in the basin was begun in 1904 at the Irshinskoe deposit; comprehensive development of the basin was begun in 1939. Principal deposits include Berezovskoe, Barandatskoe, Itatskoe, BogotoPskoe, Nzarovskoe, Irsha-Borodinskoe, Abanskoe, and Saiano-Partizanskoe. The coal-bearing series of the Kansk-Achinsk coal basin is composed of continental Jurassic deposits representing an alternation of sandstone, conglomerate, gritstone, siltstone, argillites, and coal beds. The predominant part is a typical platform basin with horizontal stratification approximately 200–400 m thick of weakly lithified rocks. In the southeast the thickness of the coal-bearing stratum increases to 700–800 m; it is composed of denser rocks and has folded stratification. In certain places the Jurassic is overlapped unconformably by nonproductive deposits of the Cretaceous, Paleogene, and Neocene periods. The coal-bearing capacity of extractive importance is confined to two different deposition time cycles—the Lower Jurassic and the Middle Jurassic. The basin has up to 20 working coal beds with an overall thickness of 120 m. The Moshchnyi bed, the most important bed in terms of extraction, lies in the upper horizon of the Middle Jurassic deposits and varies in thickness from a few dozen meters to 80 m.

The coals are composed of humus, with infrequently occurring interlayers of sapropelichumic coal. According to the degree of carbonification, they are brown coals (Bl and B2), with the exception of the Saiano-Partizanskoe deposit, which has hard coals (G grades); at this deposit the thickness of the beds is 1–1. 5 m and the conditions of bedding are complex. The brown coals have a moisture content of 21–44 percent, an ash content of 7–14 percent, a sulfur content of 0. 2–0. 8 percent, and a volatile-matter yield of 46–49 percent; combustion heat of the working fuel is 11. 7–15. 7 megajoules (MJ) per kg (2, 800–3, 750 kilocalories [kcal] per kg) and that of the combustible mass is 27. 2–28. 2 MJ/kg (6, 500–6, 750 kcal/kg). These coals disintegrate in air and become fines after 12–14 days. The hard coals have a moisture content of 5. 6 percent, an ash content of 10 percent, a sulfur content of 1. 2 percent, and a volatile-matter yield of 48 percent; combustion heat of working fuel is 26. 1 MJ/kg (6, 220 kcal/kg) and that of the combustible mass is 33.6 MJ/kg (8, 030 kcal/kg). The basin coals are also used as raw materials for the chemical industry. The shallow location of the coal beds and the great thickness of the Moshchnyi primary bed over extensive areas permit exploitation of the deposits by the open-pit mining method. In 1970, 18 million tons of coal were extracted. The explored Berezovskoe deposit, which has large coal reserves, is very promising. In addition to coals, the basin area has deposits of nonmetallic minerals, chiefly building materials.