Queensland's coals range in age from Carboniferous, 350 million years (Ma) in age, to Tertiary (65 Ma). The commercially significant black coals are restricted to deposits within sedimentary basins of Permian (280 Ma), Triassic (250 Ma) and Jurassic (200 Ma) age, located mainly in the central and eastern portions of the state.
The coal deposits of Permian age are by far the most commercially important. Of the State's black coal inventory totalling in excess of 30 billion (x109) tonnes (measured and indicated resources), Permian coals account for approximately 75% of the total resources, including almost 100% of the coking coal and about 60% of the thermal coal resources. Permian coals within the Bowen Basin in central Queensland account for approximately 70%, of the State's coal inventory while Mesozoic coals found mainly in the Clarence-Moreton, Surat, Callide and Tarong basins make up the remainder. Shallow coal potentially amenable to open-cut mining makes up about 55% of the inventory, with the remaining 45% present at greater depths.
The most important Permian coal basin is the Bowen Basin, which is exposed in a large, triangular-shaped area of central Queensland, 600km long and up to 250km wide. The basin extends south in the sub-surface beneath Mesozoic sediments of the Surat Basin, and connects with the Gunnedah and Sydney Basins in New South Wales.
Along the structurally disturbed north-eastern edge of the Bowen Basin, the coals range ........
