A bubbling pool of mud is on the move, and no one knows why

Traveling at about 20 feet a year, the muddy mystery has no obvious driver—and so far, it can't be stopped.

When it comes to matters of geology and rumbling earth in California, the San Andreas Fault is usually the star of the show. But this time around, the area near the infamous fault has caught people’s attention due to a mysterious pot of bubbling mud.

Refusing to stay in place, a roiling mass of carbon dioxide and slurry-like soil is migrating across the state at a pace of 20 feet a year. So far, it’s carved a 24,000-square-foot basin out of the earth, and it’s set to continue its crusade until whatever’s driving it dies out. Scientists currently have no real idea why it’s moving or if it can be stopped.

So, what do we know about it?

This curiosity appeared

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