Summary of How Wave Rocks Are Formed

The key stages of forming a ‘wave rock’:

Subsurface weathering (the main process)
The granite formed deep underground around 2.7 billion years ago. Over time, groundwater percolated down through cracks and joints in the rock, causing deep chemical weathering. This rounded the edges of the granite and weathered it unevenly beneath the surface, creating a curved, wave-like profile long before it was exposed.

Exhumation
Gradual erosion removed the overlying weathered material and regolith, exposing the pre-shaped granite surface. The wave-like form was therefore largely developed underground before being revealed at the surface.

Surface wash
After exposure, water flowing down the rock face deposited minerals, primarily iron oxides, iron hydroxides and carbonates. These deposits produced the distinctive grey, red and ochre streaks visible on the wave faces today.

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