Illawarra Coal Measures
The Illawarra Coal Measures is a group of sedimentary rocks occurring in the Sydney Basin in eastern Australia. This stratum is up to 150 metres thick. Formed in the Late Permian, it comprises shale, quartz-lithic sandstone, conglomerate rocks, chert, with sporadically carbonaceous mudstone, coal and seams of torbanite. Coal mining of these measures remains a significant commercial enterprise to the present day. One of the abandoned coal mines in the Blue Mountains is now a tourist attraction.