1.2.1 Available coal and coal seam gas resources

Summary

Coal is currently mined from four mines in the geological Clarence-Moreton and Surat basins in the Maranoa-Balonne-Condamine subregion. Although the southern part of the Bowen Basin is also in the subregion, its known economic coal deposits are north of the subregion boundary, so are not assessed in this bioregional assessment.

The Clarence-Moreton and Surat basins merge across the Kumbarilla Ridge. Their economic coal deposits occur in the Middle to Upper Jurassic Walloon Coal Measures. Coal seams in the Walloon Coal Measures of the Clarence-Moreton Basin are generally interbanded with mudstone and siltstone, and individual coal plies (layers within the coal) are generally less than 1 m thick. The major coal deposits in the Surat Basin Walloon Coal Measures occur in the geographic areas of Macalister, Brigalow and Chinchilla. Targets for coal seam gas (CSG) in the Maranoa-Balonne-Condamine subregion are the seams of the Walloon Coal Measures of the Surat Basin in the central-northern and central-eastern part of the subregion. CSG production occurs from the Taroom and the Juandah coal measures. No significant volumes of CSG are expected to be present in the Surat Basin in the most north-western part and the eastern part of the subregion due to the proximity to the basin margins. The coals here are shallow and gas is expected to have been desorbed over time.

The Bandanna Formation of the Bowen Basin has been targeted for CSG exploration in the north-western tip of the subregion. However, the coals were not found to have potential for CSG recovery. The coal seams of the Clarence-Moreton Basin, in the eastern part of the Maranoa-Balonne-Condamine subregion, have not been explored for CSG as of yet.