Singing Sand: Cannon Beach, Oregon

This week we have some sand from Cannon Beach, Oregon, which is most famous for this big, beautiful rock:

CannonBeach
Haystack Rock on Cannon Beach, Oregon.

Located on the Oregon coast just south of the Columbia River mouth, I passed through Cannon Beach last summer on my drive to Vancouver.

The most peculiar thing about this sand was that it squeaked when I walked on it. You read that correctly- it made a squeaky noise when you stepped in it, which was a delightful surprise.  I had heard about this phenomenon before, but never experienced it myself.  “God, that’s weird!” says one Youtuber after running their hands through the sand at Cannon Beach:

This “singing sand”, is due to localized shear: as you step into the sand, it causes the grains to rub past one another and generate sound [Humphries, 1966].  This tends to happen if the sand grains are well-sorted (all more or less the same size) and highly spherical [Lindsay et al., 1976].  In the photograph below, the sand grains don’t look particularly spherical, but they are indeed quite consistent in size (just compare with one of the more poorly-sorted samples we looked at in previous weeks).

CannonBeachOregon_000001
Squeaky sand from Cannon Beach, Oregon.

However, sand does not always sound so cute: it can also make apocalyptic booming noises“Booming sands” have been documented before in sand dunes, sounding like the world’s most enormous and terrifying swarm of bees. The sound seems to depend on the grain size and the layer of sand that is avalanching down the slope[Vriend et al., 2007], although there is still some debate about the actual mechanism.  

Something to think about the next time you hear a strange noise at the beach or in the desert!

Sources

Andreotti, B., Bonneau, L., & Clément, E. (2008). Comment on ‘‘Solving the mystery of booming sand dunes’’by Nathalie M. Vriend et al. Geophys. Res. Lett35, L08306.

Humphries, D. W. (1966). The booming sand of Korizo, Sahara, and the squeaking sand of Gower, S. Wales: a comparison of the fundamental characteristics of two musical sandsSedimentology6(2), 135-152.

Lindsay, J. F., Criswell, D. R., Criswell, T. L., & Criswell, B. S. (1976). Sound-producing dune and beach sandsGeological Society of America Bulletin87(3), 463-473.

Vriend, N. M., Hunt, M. L., Clayton, R. W., Brennen, C. E., Brantley, K. S., & Ruiz‐Angulo, A. (2007). Solving the mystery of booming sand dunesGeophysical research letters34(16).

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s