A massive sinkhole in western Kansas continues to grow. The sinkhole recently developed in Wallace County, near the town of Sharon Springs.
By the time it was noticed by a rancher, the hole was more than 200 feet across and 90 feet deep.
The sinkhole has taken many by surprise, though not Rex Buchanan, who heads the Kansas Geological Survey.
"Certainly, the location isn't surprising. Wallace County has had sort of a history of producing these things, and I've been to some of those locations, so in that sense it's not surprising," Buchanan said. "This is a pretty good-sized one, but the other ones out there are pretty good-sized as well. This doesn't occur every day, but it's certainly not out of the ordinary."
Buchanan said sinkholes like this one are created by the dissolution of underlying rock deposits, such as chalk or salt.
Some have suggested this sinkhole was caused by the removal of too much water from the Ogallala Aquifer, or perhaps the collapse of an old oil well. Buchanan says that's not the case because the aquifer is not present in that location, nor are there any oil wells in the immediate area.