During the Permian, what is now the Perth Basin was the eastern half of a rift valley that formed as the continental plates were pulled apart.
This pulling apart, which continued until the Jurassic, led to the central zone subsiding as a graben allowing the sea to enter with the subsequent deposition of transgressive marine sediments.
The Quaternary and recent sedimentation of the Perth Basin is represented by thin, impermanent sand dune systems, biogenic limestones, sandstones and some shales deposited during the last ~20 million years and during ice ages.
The Perth Basin is also prospective for natural gas and oil, with recent exploration wells, including Origin Energy/Arc Energy's Hovea 2, confirming large resources of natural gas, but difficult reservoir geology and characteristics have prevented the full utilisation of these energy reserves.
[3] Due to its shape and size, the basin has been surveyed and studied in distinctions such as offshore[4] and onshore,[5] north[6] south,[7] and central[8]