Each year the winter whitewater carves out a tiny bit more rock, and each summer we see the ripples in the granite.
It’s from the foothills of the Darling Scarp, which is on the edge of the ancient Yilcarn Craton — from the Archaean Eon — one of the oldest lands in the world (mostly about 3 billion years old and over 4 billion in the Jack Hills range far far to the North). The SouthWestern edge of the Craton is 2.6 billion years old. I don’t know if this rock has been around that long. Perhaps someone with more geology knowledge can tell us? Avon River, Bells Rapids.