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The Race Track Perhaps one of the most exciting locations in Death Valley National Park. The Race Track is famous for one of the most unusual sights, rocks that have left their own tracks on the surface of this ancient dry lake. It is said that nobody has ever seen them move. Studies have been done, and theories abound. The most logical answer, is that the elements of strong wind, and a wet surface need to be present. The dry lake is composed of silt deposits. Silt, when wet is as slippery as ice. If you introduce a strong enough wind force, a rock with a reasonably 'high' profile, can be pushed along the surface. The larger the rock, the greater the wind force required. Some tracks are as straight as an arrow, others seem to wander back and forth, even doubling back on themselves. The source of the rocks lies at the southern end of the dry lake. Exfoliation deposits the rock onto the dry lake, then in time the wind takes over. Rocks vary in size from five or six pounds, to nearly seven hundred. The most illogical suggestion is that ice is involved. I have had many people confront me with this scenario, and I have a tough time keeping a straight face, whenever they do. When we look closely at the tracks these rocks leave, we can easily see that they (the rocks) leave a depression in the surface. By definition a 'depression' requires a fluid surface. When the rocks stop they sink a little further into the surface. This does a couple of things; first it makes it harder for the wind to raise the rock up over the edge of this depression that the rock is sitting in, (the next time it moves) and secondly it creates an area that can fill with water. If ice were to be involved, that frozen water would surely 'lock' the rock in place. I believe that the greatest force required is that initial movement of the rock, to get it up and out of it's half inch-or-so 'home' This explains why so many of the rocks travel great distances in a single event, the hardest part is getting them started. Once they are moving, I believe that they move fairly easily. If you still think ice is involved, try this experiment at home. Open your freezer door, empty it out. Go to the back yard and find a small rock. Place it in the freezer. Now take a spray bottle and spray water on the horizontal surface, make sure there is a small amount of standing water, and that there is some around the rock. Capillary action will draw it to the edges of the rock. Close freezer door and wait one hour. Open freezer door and try to move the rock.......... Case closed. Finding the rocks. Starting out from the Ubehebe crater, a 27- mile (43km) dirt road takes you through a field of Joshua trees, to the aptly named Teakettle Junction, then on to The Race Track Valley. This road is usually passable by two-wheel-drive vehicles, but storm run off and flash floods can cause serious erosion. It is always advisable to check with Park Rangers concerning the condition of this road. A small parking area at the southern end of the Race Track is the best place to start your walk to the dry lake. Walk about a quarter of a mile out onto the dry lake and you will start to see the rocks.
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