A big rock sticks up out of the mud. It's too heavy to pick up. Yet, it has mysteriously moved. A trail shows where it moved across the dirt.
Many of the big rocks in this part of Death Valley in North America have moved. How? No one has ever seen it. It’s a mystery.
Boulders mysteriously zig and zag in Death Valley, California, U.S.A.
North
America
Death
Valley
A man takes a photograph of boulders and their trails.
Searching
for a Cause
People have wondered about the big rocks. Some people think the rocks are magical. Others think the rocks were moved by people playing a prank. Scientists wanted a better answer.
Maybe the rocks were sliding downhill? No. These rocks actually moved uphill. Maybe the rocks were pushed by winds? No wind seemed strong enough.
This video follows the trail made by a heavy stone.
Cold Clue
One scientist realized an important fact. The rocks only moved in winter. During winter, this place floods. The water freezes. It forms ice. A small wind might be enough to push the rocks across ice.
No one has seen the rocks move. So, no one can be sure how they do it. This mystery is unsolved!
Scientist Ralph Lorenz thinks ice and wind may move the rocks.