Death Valley National Park
The Sliding Rocks Mystery of Racetrack Playa
As I stood out in the desert pondering the muddy water and my misfortune, everything became clear. A solution to at least part of the puzzle of the sliding rocks was right there on the desert playa floor. Observations from yesterday and today crystallized into an explanation for how even those big heavy rocks, and small ones too, could move across the lake bed leaving long parallel equidistant furrows in the mud turning as if in formation.
THE WIND CAN MOVE THE WHOLE LAKE!
That is, the large shallow pool of water on the playa can be radically shifted from end to end and side to side according to which way and how hard the wind is blowing. This we saw with our own eyes.
It follows then that when ice forms in winter on water on the playa the wind can shift the body of water and the frozen surface as well. Huge ice rafts easily push the rocks frozen in the ice as the whole shallow lake shifts in position according to the direction of the wind. The varied tracks can be explained by contemplating the nature and the break up of the ice and how different floating rafts behave as they jostle each other as the water and ice are blown across the playa. It’s a matter of scale. Even the largest rocks can be small considering the mass of ice floating in the lake.