Brecheisen Week 2 Wave Rock

This week I visited Australia in my search for igneous rock formations. I had heard of a famous formation near Hyden, Australia. My trip did not disappoint, as I was able to visit Wave Rock. This granite cliff is nearly 15 meters high and 110 meters long and resembles a giant wave. I did not spend much time surfing in Australia as this igneous rock formation is hundreds of kilometers away from the coast. I was fascinated by the appearance of this cliff. I have never seen anything like it. Its distinguishing characteristics are its wave-like appearance and many colors. I was very surprised that minerals could form in such a way and wanted to learn more.

            As it turns out, this formation is an outcrop of the Yilgarn Craton. This is the oldest of the cratons that formed the Australian continent. This formation is very hard and resistant to erosion, thanks to the fact it is granite and part of a craton. In fact, it wasn’t water erosion that created the unique wave shape. It was actually scarp foot weathering. This is the effect of humic acid in the soil dissolving the sides of the cliff as it slowly emerged. Due to the hardness and resistance to water, water would run off the sides and mixed with the soil that once covered Wave Rock. The soil slowly eroded away over time, but the granite remained, only eroded by the humic acid. The runoff water that attributed to this humic acid also created the vertical streaks of various colors in the cliff face.  The granite formed underground from the cooling of magma and formed the base of Australia. When the craton rose from the sea, the granite cliff began taking shape. It is a coarse-grained mineral formation and crystals taken at the site were dated to put this cliff at 2.7 billion years old (Monroe, 2015).

            This formation has a rich history and has become a popular tourist attraction. Much like the Leaning Tower of Pisa, many original tourists come to this spot to be photographed riding the wave. This was a fun trip and I hope to come back one day.

Reference

Monroe, M. (2015). Wave Rock. Retrieved from https://austhrutime.com/wave_rock.htm