Geology of the Great Sandy Desert

The sand dunes of the Great Sandy Desert mainly trend WNW-ESE, and obscure a fascinating geology beneath. The dunes are Quarternnary and are made up of red siliceous sand. Underlying are flat lying sedimentary rocks of the Canning Basin which initially developed in the Early Paleozoic as an intracratonic sag between the Precambrian Pilbara and Kimberley Basins. The basin contains two major northwesterly trending troughs separated by a mid-basin arch, and marginal shelves.
The northern trough is divided into the Fitzroy Trough and the Gregory Sub-basin, which are estimated to contain up to 15 km of predominantly Paleozoic rocks.The southern trough includes the Kidson and Willara Sub-basins, in which there are thinner sedimentary successions (4–5 km thick) of predominantly Ordovician to Silurian and Permian age, with extensive Mesozoic cover. The Canning Basin drainage is limited to short ephemeral creeks and rivers, which only flow after heavy rainfalls. The desert comprises two ancient inactive river basins that are divided by a low watershed. The watershed is a lateritic surface that forms the Anketell Range in the west and Southwest Tableland in the east. North of the watershed Sturt Creek (now only visible from satellite imagery) once flowed across the desert to Mandora on the 80 Mile Beach. The southern basin contains Percival Lakes which represent an ancient river system. Calcrete and evaporite outcrops are associated with palaeodrainage systems that traverse the desert.
The Rudall River is a significant wetland/ecological refuge within the Great Sandy Desert which contains major permanent waterholes and soaks and flows approximately 120km into Lake Dora (30, 000ha)
Beneath most of the Great Sandy Desert is a sub artesian basin which is tapped by numerous Aboriginal wells and also the wells constructed on the Canning Stock Route.

Geological Maps
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Calvert Expedition
The extraordinary tragic story of perhaps the most extreme outback expedtion in Australia's history.

History of the Canning Stock Route
Read about the extraordinary task undertaken to survey and construct the Canning Stock Route

Travel the Canning Stock Route
Join an expedition to cross the Great Sandy Desert along the worlds longest most remote heritage trail.