BasinsPerth

the Basins Perth is forms a significant freshwater aquifer. It is composed primarily of non-marine fluviatile feldspathic, poorly sorted sandstones which are porous and poorly cemented, hence allowing for considerable groundwater reserves. The Yarragadee Formation grades from a shale-siltstone dominated base to a cleaner sandstone in the upper portions of the formation, probably representing increased subsidence or filling of the basin during the late Jurassic. Cadda Formation  conformably underlies the Yarragadee Formation and is composed primarily of shale and siltstone, with occasional beds of very coarse sandstone. The upper portions of the unit are composed of a marl grading into a marine limestone, representing stable tectonics at this time. Cattamarra Coal Measures  are a sequence of non-marine, probably fluviatile sandstones, shales and silts including bituminous coal, and are up to 300 m thick. The Cattamarra Coal Measures conformably overly the Eneabba Format