Australia is well known as one of the word’s prime locations to surf the perfect wave. And near the town of Hyden is a wave 110 metres long. There’s only one problem: it’s made of solid rock.
Towering 15 metres into the air, this granite cliff, called Wave Rock, formed over 2,500 million years ago. As one side of an inselberg (an isolated hill or mountain rising from a plain), this concave cliff is known as a ‘flared slope’.
Created by wind and rain erosion, it is comprised of coarse-grained porphyritic granite and igneous rock embedded with different minerals and crystals. As wind and rain has battered the wall, softer rock at the base has been undercut, producing its wave-like appearance.
Rainfall has not only helped to create the rock formation’s shape but has also decorated it with a series of red, brown and yellow stripes. Although they might seem hand-painted, each vertical stripe is an indication of different mineral deposits washed down the slope, reacting with the water and producing different colours.
Water-loving algae also play a role in the cliff’s colourisation. Usually staining the rock black, these tiny organisms develop a brownish colour during the dry seasons.