The Racetrack Playa Sliding Rocks Unexplained

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• Racetrack Playa at the Death Valley in California is one such place where you’ll find long tracks of moving stones but you’ll never find a stone really moving. The tracks are of different lengths, and directions. Some are short while others are as long as 1500 feet.

• These tracks have been formed without any human or animal intervention. 
• Apparently some rocks just move by themselves. No one has seen the stones in motion. Racetrack stones only move once every two or three years. 
• The rocks weigh between 1-700 pounds (with 25-30 pounds most of them) and feature sizes of up to 30 cm. 
• Racetrack desert area is almost perfectly flat. 

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Is there a scientific explanation for this? 

Yes, but all of them turned out to be unreliable. Experts suspected animals (pushing stones in the desert?), gravity, quakes, Etc, but all these ended on a dead track.

A most recent theory :

((Focused on observations and measurements of narrowing trails, heat conductivity of the playa's rocks, water, ice and sediments, missing rocks from ends of the trails, and an intermittent spring system in the playa. Kletetschka with his team identified three groups of Racetrack playa spring lineaments, Spinal Springs, Edge Springs, and Gindarja Springs, through which additional water flows into the playa once the ice forms on the water inside the playa. This mechanism, in addition to the raft hypothesis, allows lifting the rocks by adding additional amount of water via these springs. via ))