The deposits—16th-largest coal reserves in the world, were discovered in 1991 by Geological Survey of Pakistan (GSP) and the United States Agency for International Development.
It is one of the world's largest lignite deposits discovered by GSP in 1990s, spread over more than 9,000 km2 comprise around 200 billion tonnes sufficient to meet the country's fuel requirements for centuries.
The Thar coalfield is located approximately between Latitudes 24°15'N and 25°45'N and Longitudes 69° 45'E and 70° 45'E in the southern part of Sindh Province in the Survey of Pakistan topo-sheet Nos.
It is bounded in the north, east and south by India, in the west by flood plains of the Indus River.
The climate is essentially that of an arid to semi-arid region with scorching hot summers and relatively cold winters.
It comprises Basement Complex, coal bearing Bara Formation, alluvial deposits and dune sand.
The overburden consists of three kinds of material: dune sand, alluvium and sedimentary sequence.