There are three coalfields – Auranga, Hutar and Daltonganj in the valley of Koel river, a tributary to Son river. The Auranga and Hutar coalfields are in the same alignment with those of Damodar Valley while Daltonganj coalfield is somewhat north of axial line. Hutar and Daltonganj coalfields are of economic importance. In Hutar coalfield coal seams occur in Lower Barkar . A number of coal seams have been reported. The coals are low in volatile matter (12.6%) and ash content (17.67%).
(iii) Deogarh Coalfields:
The Deogarh group of coalfields comprises three isolated Lower Gondwana sedimentary basins such as Jainti, Sahrjuri and Kundit Kuraiha. These basins forms a NW-SE trending belt and are located in the Santhal Pargana districts of Bihar . The coal seams are reported to occur in the Karharbari as well as Barkar Formation. The coals are high in ash and range in rank from Sub-bituminous B to high volatile bituminous B.
(iv) Rajmahal Coalfields:
The coalfields of this area are assuming importance lately. The unique location of the coalfields at the southern bank of the Ganges offers a good possibility of supplying coals to major power stations of North Bihar , North Bengal and Bangladesh . Based on the coal of this region, a Super Thermal Power Station has been built at Farakka. There are five coalfields in this area. Coals of this region are sub-bituminous to high volatile bituminous in rank.
(v) Hazaribagh Coalfields:
Girdih or Karharbari coalfield is the most important coalfield amongst the Hazaribagh group of coalfields. Some of the best coking coals were extracted from this coalfield. Besides, Girdih coalfield is the type area of Karharbari Formation. The coal from the seams are low in moisture (1.40-1.80%), low in ash (9-12.6%), low in volatile, low in sulphur (0.5%) and phosphorous (0.01%).
(c) COALFIELDS OF CHHATTISGARH AND MADHYAPRADESH
About one-fifth of the estimated reserves of the country are located in coalfields of these states. Coalfields of these states are traditionally put into four groups: (a) Central Indian coalfields (Singrauli, Sohagpur, Umaria, and Johilla), (b) Satpura coalfields (Pench, Kanhan and Pathakhera), (c) North Chhattisgarh coalfields (Chirimiri, Kurasia, Bisrampur, Jhilimili, Sonhat, Sendurgarh, Tatapani-Ramkola), and (d) South Chhattisgarh coalfields (Hasdo- Arand, Korba, Mand-Raigarh). Madhya Pradesh and Chhattisgarh produced 29.2 per cent of total production in India .
(i) Central Indian coalfields:
This field is situated mostly on the border of Uttar Pradesh and Madhya Pradesh. While most of the field is in M..P. a part of it is situated in the Mirzapur district of U.P. In this coalfield coals have been found in Barkar and Raniganj Formation, there are four coal seams. These coals are useful for thermal power generation.
2. SOHAGPUR COALFIELD
Sohagpur is another important coalfield in the Son Valley . Barmni-Chilpa fault trending east-west has divided this field in two parts. In the southern part of the fault there are 5 coal seams within the Barkar Formation. The coal contains 4 -7 %moisture and 20-27 % ash. The coals on the north of this fault are characteristically different from the coals occurring south of the fault. Coking coals have been found in the north of the fault.
3. UMARIA COALFIELD
This coalfield is situated on the Umrer river a tributary of the Son river. The Lower Gondwana rocks are well developed in this coalfield. Six coal seams have been found in this field. The coals are relatively high in moisture (7-10%) and high in ash (18.6-29.4%).
4. JOHILLA COALFIELD
This coalfield is situated in the Valley of Johilla River. In this field, Talchirs, Barkars and beds of Raniganj age are developed. Johilla seam is the most important seam in the northern area. The seam has a high moisture (10.8%), ash (17.9%) and volatile matter content (31.7%).
(ii) Satpura Coalfields:
Satpura coalfields lie within the Pench-Kanhan-Tawa valley, south of Narmada river, known as Satpura Gondwana Basin . In this region, Gondwana lie in a syncline trending ENE to WSW. Important coalfields in this region are:
1. MOHPANI COALFIELD
This coalfield is one of the country's oldest coal-bearing areas. It is situated in the west of Mohpani. In this coalfield, Talchir and Barkar Formations are overlain by the Upper Gondwana rocks of Bagra Formation (Mahadeva Group) and Jabalpur Formation. The coal seams in this area are weakly coking with moisture content ranging from 4 to 6%.
2. PATHAKHERA COALFIELD
This is an important coalfield in the Tawa valley. In the vicinity of Pathakhera three coal seams have been encountered by boring. The top seam is of poor quality and the other seams are comparatively better in quality.
3. KANHAN VALLEY COALFIELD
There are the most important coalfields of Satpura region. Coals of Kanhan valley are characteristically coking particularly in Damua, Kalichhapar and Rahikol collieries. The area is covered by Barkars. The area is intersected by number of faults. The coal in this region generally is of low moisture and ash content and is of coking quality.
4. PENCH VALLEY COALFIELD
This area is situated in the north-west of Chindwara and lies in the east of Kanhan valley coalfields. The rocks of Barkar Formation are exposed in the area. Important coal seams are exposed in Gajandoh area, Barkuhi area, Chandamata - Dongar Chikhli area etc.
(iii) North Chhattisgarh Coalfields:
1. TATAPANI RAMKOLA COALFIELD
This coalfield is located in the Surguja District of Chhattisgarh and covers an area of about 260 sq.km.. It consists of two separate areas – the eastern and western. The eastern portion is called Tatapani area where 5 coal seams occur in the Barkar Formation. The coals in the area are non-coking with low ash content. The western part or Ramkola area is separated from eastern part by a patch of Upper Gondwana rocks called the Rajkhatra tract. There are 5 coal seams in the Barkar Formation. The ash content varies between 17 and 34%.
2. JHILIMILI COALFIELD
This village is situated around village Jhilimili. The Lower Gondwana is represented by Talchir and Barkar rocks. The Talchir rocks are exposed towards the south of the field. Barkar rocks, consisting of sandstone, shale and coal seams mainly occupy the northern area. The coalfield may be divided in to three areas: (i) Northern area; (ii) Central area; (iii) Southern area. In the Southern area good exposures of coals have been noted from several parts Out of which Manikmara is important.
3. SONHAT COALFIELD
This coalfield lies west of the Jhilimili coalfield forming the eastern extension of Sohagpur coalfield. The Barkar rocks which occupy the Sonhat plateau have been broadly divided in to three divisions. The lower division consists of more than 15 coal seams. The middle division is devoid of coal seams. In the Upper division although Barkar strata is of considerable thickness in the field, the number of coal seams and their thickness is poor.
4. CHIRIMIRI AREA
Three seams of the Karakot horizon are the most important seams in this area. The composite seam is being worked in the collieries of Chirimiri, New Pouri (New Chirimiri) and Kurasia.
5. KURASIA AREA
In the eastern sector drilling has proved the existence of workable coal horizon in this area. These are: Duman seam; Kaperti seam; Shorgela seam; and Kotmi seam.
6. BISRAMPUR COALFIELD
This coalfield covers an area of about 1036 sq.km. Coal bearing Barkar rocks are developed to a thickness of about 150 metres. Several coal seams have been reported from different localities. In the south-western part of the field detailed prospecting conducted by Indian Bureau of Mines has indicated more than one horizon of coal. Pasang seam is the thickest seam in the horizon. The coal is of non- coking type in this seam.
(iv) South Chhattisgarh Coalfields:
1.HASDO – RAMPUR OR ARAND (SURGUJA) COALFIELD
This coalfield extends from Rampur and Paharbula Lappas in Arand valley to Hasdo river in Bilaspur district. This coalfield is divided in to four parts:
- The eastern or Rampur section in Rer (Arand) valley
- North central (Paharbula) area
- South Central (Uprora) area
- Western (or Mation) area beyond the Gej and Hasdo rivers
The quality of coal in this field varies widely. The contents of moisture varies from 1.56 to 7.40% and ash from 11.26 to 25%.
2. KORBA COALFIELD
Korba coalfield is located in Korba district of Chhattisgarh and covers an area of about 530 Sq.Km. The coalfield is named after the village Korba on the eastern bank of the Hasdo river which is tributary of the Mahanadi river. The Barkar Formation is the coal bearing measures. As per GSI a total of 10075 Mt. coal reserves available in Korba coalfield. The deposits are restricted into two distinct zones:
- Thick seam/qurriable power grade zone comprising of grade E, F, & G having reserves of approx. 9068 Mt.
- Thin seam /underground superior grade zone comprising of grade B to D having reserves of approx.1007 Mt.
3. MAND-RAIGARH COALFIELDS
These coalfields are situated in Raigarh district of Chhattisgarh and covers an area of about 520 sq. km. This coalfield comprising of grades A to G and having reserves of 18522.93 Mt. Here large potential for power grade coal are present and may be exploited through open-cast mining.
(e) COALFIELDS OF MAHARASHTRA
(i) Coalfields of Nagpur region:
1. KAMPTEE COALFIELD
This coalfield is situated about 19 km NNE of Nagpur. This coalfield can be called as a hidden coalfield as the coal bearing rocks are not exposed anywhere. Later on geophysical prospecting technique was applied in this coalfield for the first time for exploration of coal in India . Detailed exploration has proved a large deposit of coal in the following three blocks:
- Ghatrohan area to the east of the Kanhan river
- Silewara area to the west of the Kanhan river
- Bina area to the south of the Kanhan river
Five workable seams have been proved over the three blocks. The moisture content of the coals varies from 8 to 11% and the volatile matter from 33 to 43 %. The coals are non-coking.
2. BOKHARA COALFIELD
This field is situated 9 km north-west of Nagpur railway station. Seven coal seams have been proved. The moisture content of the coal seams varies from 8 to 11% and the volatile matter from 24 to 29 %. The coals are non-coking.
3. UMRER COALFIELD
Umrer is a small town situated about 44 km south-east of Nagpur . The coal bearing strata is nowhere exposed at the surface. The coal bearing Barkars rocks lie over Talchirs. There are four workable seams in the area.
(ii) Wardha Valley Coalfields:
The Wardha valley coalfields are situated in the valley of Wardha river, lying mainly in the Chandrapur district. The coalfields extend in a NW-SE direction extending over a distance of 115 km and cover an area of about 4130 sq. km. The coal bearing Barkar rocks are only 76 metres thick and occur in patches. Rarely coals are found in the outcrops.
(f) COALFIELDS OF ANDHRA PRADESH
In Andhra Pradesh important Coalfields lie in the Pranhita – Godavari Valley . In continuation of the Wardha valley there are coalfields in the Pranhita-Godavari valleys covering an enormous area of over 9000 sq. km. The Lower Gondwana rocks consisting of Talchir, Barkar and Kamthi are well developed in the area. The exposures of Barkar rocks are few. The coalfields are traversed by post-Kamthi faults. The characteristic of the coalfields is that these are devoid of igneous intrusions. Based on geographical and geological considerations, the Godavari valley coalfield is divided in to twelve coal belts. Ramagundam Coal belt is one of such coal belts located along the western margin of the Godavari valley coalfield. Important coalfields of the area Tandur Coalfield; North Godavari and South Godavari Coalfield; Karlapalli or Kamaram Coalfield; Ramagundam Coalfield etc.
(g) COALFIELDS OF ORISSA
Out of 57 Gondwana and 14 Tertiary coalfields considered for the national inventory of the coal, Orissa state has only two-intact geologically only one and half coalfields. Yet its share in the reserve so far established in the country amounts to 23.6%. The famous coal bearing basins are Ib-River coalfields & Talcher coal fields and as a sequel to which these coal fields have been added advantage of being accorded most favored coal fields status by nature as far as qurriable potentiality is concerned. A substantial qurriable reserve has been located in northern part of Ib-River coalfield (Gopalpur area) and towards its south-eastern extremity in Khinda-Talabira area. Occurrence of coal seems has also been reported from Raniganj Formation of Ib-River coalfield very recently. The importance of Orissa coalfields is further enhanced due to their proximity to the east coast.
Gondwana Coals occur in India mainly along the three master Gondwana basins, viz. Damodar Valley , Son-Mahanadi Valley and Gondwana Valley . Coalfields of Orissa constitute the southern part of the Son-Mahanadi Valley basin. Except the Ib-River coalfield and Talcher coalfield, there are Four more Gondwana basins in Orissa:
a) ATHAGARH basin
b) GAISILAT basin
c) ATHAMALIK basin
d) KATRANJIA basin.
(h) UPPER GONDWANA COALS
It includes coalfields of Gujarat . Sub-bituminous type of coal is found in association with Upper Gondwana sediments (Cretaceous) in the district of Kutch, Surendranagar and Mehsana district.