1.2.1.1.1 Maules Creek sub-basin

The major coal deposits of the Gunnedah Basin are shown in Figure 5 and are hosted within the Maules Creek Formation and the Black Jack Group (Tadros, 1993) of the Maules Creek sub-basin, a narrow north-south oriented trough (Figure 4, and see Figure 18 in companion product 1.1 for the Namoi subregion (Welsh et al., 2014)). The Maules Creek Formation contains up to 25 correlated coal seams that are generally thickest close to the Boggabri Ridge.

Most of the seams are more than 3.5 m thick, with the Braymont Coal Member being the thickest (up to 9 m) in the Maules Creek and Boggabri areas. Coals of the Maules Creek Formation are rich in vitrinite (up to 80%) and also contain high liptinite contents, with vitrinite reflectance values ranging between 0.5 and 0.9%. These coals are typically low-ash, high-volatile, low-sulfur thermal and coking coals.