Sliding Rocks in Death Valley

My hubby sent me this cool story about rocks that slide across the Death Valley floor in an unknown manner. There are theories about how it occurs. The one that is most prevalent is that it is a combination of ice and wind that helps these rocks on their way. But the kicker is no one has ever actually seen them move! We can only see the trail that is left behind....Yes, you are now entering the Twilight Zone....

For more cool photos and interesting theories, check out the story at Geology.com