According to a story from ABC, a 120-foot wide and 30-foot deep sinkhole appeared on July 19th in Spring Hill. Sinkholes happen in Florida with alarming regularity, but what makes this one special to me is the way an eyewitness described it:
"Out of nowhere the earth just went straight up in the air and exploded up in the air," said Margaret Helmick, who lives in the neighborhood.
This makes it sound much less like a mere incidence of subsidence, and much more like bottled-up methane or hydrogen sulfide underground. I'm also reminded of another recent incident, the Yamal Crater in Russia, which has baffled scientists by its abrupt appearance.
No one's sure when the giant chasm occurred, but it was first noticed on July 11. That its location is near a natural gas field has caused some concern, and though it was originally thought to be a meteor impact site, it is now apparent that whatever happened, it happened from inside and exploded outward.