Mount Augustus (Western Australia)

According to the Geological Survey of Western Australia, Mount Augustus is an asymmetrical anticline (rock layers that have been folded into an arch-like structure) which is steeper on its north-eastern side than the south-west.

The rocks consist of sand and gravel that were deposited by an ancient, south-easterly flowing river system that drained the region about 1,600 million years ago.

The river deposits consolidated to form sandstone and conglomerate, and were then buried beneath younger marine sediments, which were laid down when shallow seas covered the region between 1,600–1,070 million years ago.

Erosion has also removed sandstone and conglomerate from the north-western end of Mount Augustus to expose the underlying granitic rocks at The Pound.

An inquest into the deaths by government authorities suggests to close the summit trail between September and March for the sake of unwary hikers who do not appreciate the treacherous conditions.