Shot at Eureka Dunes in Death Valley NP. Those are my foot prints after walking down from the dune on the upper right. Every once and a while my right foot would cause a small cascade that would produce a low pitched rumble like a bassoon that would last several seconds. I had read about the "sounds" of Eureka Dunes but it was quite an experience to hear it (and feel it) for yourself.
Death Valley, CA
Canon 5D mkII, Canon 17-40 f4@24mm, f16@1/250th sec, ISO 640