Thirty-two shallow auger holes up to 2.76 m deep were drilled into the floor of Lake Cadibarrawirracanna, situated 70 km west of William Creek, in a search for possible potash-rich brines trapped by the lake sediments. The lacustrine sediments were shown to be very thin, and the entrained brines have a low potassium content, of the order of 580 mg/l, while their volume is potentially quite small. It was shown that the concealed contact between the Cadna-owie Formation and the Bulldog Shale trends roughly east-west through the centre of the lake.