Authorities are concerned that a woman who went missing while searching for her cat in western Pennsylvania may have been engulfed by a sinkhole, likely resulting from mine subsidence.
Rescue teams have not detected any signs of 64-year-old Elizabeth Pollard since she vanished on Monday evening, but a sinkhole emerged around the same time approximately 20 feet (6 meters) from her car, prompting fears that she may have fallen in. Her granddaughter was discovered safely inside the vehicle hours later.
Although sinkholes are often linked to mining activities, they can occur independently. In 2013, a man was killed when a sinkhole suddenly appeared beneath his house in central Florida, a region known for its porous limestone that leads to thousands of sinkholes annually.
Florida, Texas, Alabama, Missouri, Kentucky, Tennessee, and Pennsylvania frequently experience the most significant issues due to sinkholes, although fatalities are uncommon.
What exactly are sinkholes?
A sinkhole is defined as a section of land that lacks natural external surface drainage and can develop when the ground beneath the surface is unable to bear the weight of the land above it, as per the U.S. Geological Survey.
Typically, the ground remains stable for a time until the subterranean spaces enlarge beyond capacity. When support becomes inadequate for the land situated above these voids, a sudden and dramatic surface collapse may occur.
How prevalent are sinkholes?
Sinkholes are predominantly found in areas termed karst terrain, characterized by rocks like limestone that can be eroded by groundwater. They can also result from abandoned underground mines.
Florida is particularly vulnerable to sinkholes due to its positioning over limestone.
What is the size range of sinkholes?
Sinkholes can vary from just a few feet across to those that extend over vast regions, sometimes encompassing hundreds of acres. The hole that may have absorbed Pollard was roughly the size of a manhole cover upon its detection on Tuesday morning.
Their depths can fluctuate from only a few inches to over 100 feet (30 meters). Some sinkholes feature shallow bowl or saucer shapes, while others possess vertical walls. Certain sinkholes can retain water, forming small ponds.
What triggered the sinkhole in Pennsylvania?
The sinkhole that appeared in the Unity Township area of Marguerite, where search and rescue teams are still hopeful of finding Pollard alive, formed above the Marguerite Mine site, which was last