North East Coal Fields in India: Workable coal fields seams occur in Assam and Meghalaya at three separate geological horizons, two of which belong to the Lower Eocene of Meghalaya and one in Oligocene of upper Assam. The rocks concerned belong to the Jaintia Formation in the first two regions and to the Barail Formation in the other.
These coals, though of Tertiary age, are of a higher rank than many other young coals. They are advanced types of meta-lignite approaching bituminous coals in composition.
The important coal-fields are located at:
- Namphuk, Namchik, Makum, Jeypore, Nazira, Jhanzi and Disai of upper Assam;
- Longloi hill, Dissoma, Nambor, Doigrung, Charigaon, Cherrapunji, Mawlong, Lakadong and Salunga of the Khasi and Jaintia hills;
- Kharibari, Rongrengiri, Daranggiri, Dograng, Waimong, Tura hill and Siju of the Garo hills.
The major coalfields of the north-eastern region are located at:
- Makum (Reserve 235 million tons),
- West Daranggiri (127 million tons),
- Balphakram-Pendenguru (107 million tons),
- Namchik (90 million tons),
- Dilli-Jeypore (54 million tons) etc.