Australia

The rocks of the Adelaidian geosyncline are as thick as 10 mi (16 km) with sediments that have been extensively folded and subjected to faulting during late Precambrian and Early Paleozoic times (about 600 million to 500 million years ago). Some of the rocks of the Adelaidian geosyncline, however, are unaltered. These strata show evidence of a major glacial period around 740 million years ago and contain some of the continent's richest, most diverse fossil records of soft-bodied animals.

This glaciation was one manifestation of global cooling that caused glacial episodes on other continents. Geologists say this Precambrian glacial episode was probably one of coldest, most extensive cooling periods in Earth history. They also consider the Adelaide geosyncline to be the precursor of another downwarp related to the most extensive folded belts on the continent, namely the Tasman geosyncline along Australia's east flank.