The seven rocks that made Australia

Summary

Key geological events of the last 4 billion years have shaped Australia’s present day environment, economy and society; and a limited number of rocks can be chosen to represent this history. Pilbara banded iron formations and Permian coal measures of the Sydney-Gunnedah-Bowen basins are obvious candidates along with at least one of the rich mineral deposits found at Broken Hill, Mount Isa, Kalgoorlie or Olympic Dam. Early Paleozoic gold-bearing metasediments in the Castlemaine Basin, Victoria, are an undisputed member of the list given the impact of the 1850s Gold Rush upon Australian history. Gas-bearing Triassic sandstones on the North West Shelf; Cretaceous marine shales that cap the Great Artesian Basin; and the Cenozoic limestones along the southern margin, that represent the formation of the island continent and our long isolation, are just a few of the other possible candidates. The Quaternary is another key episode to include with sediments such as the Lake Mungo deposits, the post settlement alluvium or the rock we are making now in the Anthropocene.

• mineral resources
• petroleum
• economic history
• Australian geology