Coal is a combustible black or brownish-black sedimentary rock usually occurring in rockstrata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure. Coal is composed primarily of carbon, along with variable quantities of other elements, chiefly hydrogen,sulphur,oxygen and nitrogen. A fossil coal forms when dead plant matter is converted into peat, which in turn is converted into lignite, then sub-bituminous coal, after that bituminous coal, and lastly anthracite. This involves biological and geological processes that take place over time.
Some of Coal deposits:
|S. N.||NAME OF THE DEPOSIT||DISTRICT||LOCATIONl||ACCESSIBILITY||OCCURRENCE||CHEMICAL COMPOSITION / QUALITYl||RESERVE (million tons)|
|1||MAKUM COAL FIELD||Namdang Colliery (27°16°00°N 95°51°00°E),Borgolai Colliery (27°16°00°N 95°51°00°E), Ledo Colliery (27°18°00°N 95°51°00°E), Tipong Colliery (27°16°00°N 95°51°00°E)||Detail||Can be approached by both rail and roadways. Railway line is linked with the Tinsukia junction.||29 Km long and 4.6 Km wide area.,Coal bearing rocks belongs to the Tikak Parbat and Bargolai Formation||Good quality with low ash and moisture. High sulphur Moisture : 2 - 9% Sulphur: 1 - 4% Fixed carbon: 42 - to 60% Volatile Matter: 38 – 51% Calorific Value: 5035 – 7950 Kcal. / Kg.||Total Reserve: 316 Million tones. Proved Reserve: 305 Million Tones..|
|2||DILLI JEYPORE COALFIELD||Partly in Dibrugarh district (Joypore Colliery) and partly in Sivsagar district (Dilli Colliery) separated by the Dilli (Disang river.)||Latitude: 27°50°00° to 27°8°30° N Longitude: 95°15°10° to 95°15°00°E l||The coalfield is connected by a 12 Km road with Namrup railway station. The coalfield can also be approached from Sivsagar via Sonari and from Dibrugarh via Naharkatia and Duliajan..||Area of 40 km. long and 0.50 km. Wide. Four distinct geological horizons belonging to Tikak Parbat Formation exist in this area where thicker seams of coal occur towards the bottom. About ten coal seams of various thickness ranging from 0.50m to 21m are located in the lower most horizon||Good with low ash but high moisture and high sulphur Upper coal bearing horizon: Moisture : 3.7-6.7%; Ash: 5.4-24.9% Sulphur: 3.2-7.4%; Fixed carbon: 32.6 – 46.5% Volatile Matter: 32.5 – 45.5%; Calorific Value: 5035 – 6020 Kcal. / Kg Lower coal bearing horizon : Moisture : 4.2-6.4%; Ash: 2.1-28.7%||Total Reserve is around 54 Million tones. Proved Reserve is 32 Million Tones..|
|Exploration done by Directorate of Geology and Mining, Assam:||198.37 KB|