EARTH - California Sinkhole Swallows A Pond

Overnight, Mark Korb lost a pond. How did he lose a pond? A sinkhole ate it. On the morning of March 17, Korb discovered that a sinkhole had opened up under his man-made pond on this property, emptying the whole thing in a matter of hours. Sinkholes usually develop in areas where the ground is "karst terrain" - a generic name for dissolvable rock, like limestone or salt deposits. Water under the ground wears away at these rocks, creatin ...

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