The Pinnacles, Nambung National Park

The pinnacles were once a layer of soft limestone cemented together by the lime leaching from the sand dissolved by rain. This rock layer had a hard layer of calcrete on top to protect it. You can still see the white calcrete on top of these pinnacles. Cracks in the calcrete were pushed apart by plant roots allowing the soft limestone to erode away. The surrounding sands have blown away leaving only the the most resilient limestone under the protective calcrete - the pinnacles.