The basin is made of sandstone, siltstone, mudstone, coal, shale, and red beds.
In Queensland and South Australia the Eromanga Basin has been explored and developed for petroleum production.
[1] The basin contains Australia's largest onshore oilfield, the Jackson oil field.
[3] During the middle of the Cretaceous period much of inland Australia was flooded by the Eromanga Sea, which shares its name with the contemporary Basin.
Various fossil sites spanning the region record a diversity of marine life, including Plesiosaurs and Ichthyosaurs, that were abundant in the Eromanga Sea during the Aptian and Albian ages.