What Do You Suppose is Down There?
An anonymous reader recently alerted me to the remarkable sinkhole that opened up in the middle of Guatemala City on Sunday. (Thanks, Anonymous!) It's sixty feet across. And THIRTY STORIES DEEP. And it could get bigger! I've posted about this kind of phenomenon before, but the National Geographic's pictures of the latest sinkhole are absolutely amazing.
According to the experts at NG, "Sinkholes are natural depressions that can form when water-saturated soil and other particles become too heavy and cause the roofs of existing voids in the soil to collapse."
OK, I kinda buy it. But what's an "existing void in the soil?" Are we talking underground caverns, here? Enormous natural chambers thirty stories underground?
'Cause if that's what we're talking about, I have one simple question. How do we know they're empty?