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, creating holes in the ground over time. When there is a thin layer of ground above the whole, it can cave in all at once.
Twenty percent of the U.S. is karst terrain, and therefore is susceptible to sinkholes.
In this case, Sierra Collage geologist Alex Amigo told KRCA that he thinks the sinkhole could have been related to man-made caves from the gold rush:
"There was such a lot of mining activity going on we almost never know when there was some man-made type of cavity underground. And then any way that the water can make it there, maybe there was a pre existing fracture, or a fracture formed, that water could have drained very fast. "
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