Pothole or sinkhole: Which one did you see?

USGS photo of a sinkhole in Florida.
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ANCHORAGE (KTUU) - You might've recently seen a sinkhole here in Anchorage - or at least, that's what many people have begun to call them - but whether it's a pothole with a larger gaping hole underneath or a parking lot dip that's become a hazard, we looked to local scientists to learn a bit more about what we're actually dealing with.

In short, as massive as they may seem when drivers attempt to dodge them on city streets and state highways, the potholes here are nothing compared to instances of giant sinkholes, such as those that have been seen in Florida, Maryland, Texas, and others around the country and globe.

So what exactly is a sinkhole?

"In the truest sense, a sinkhole is is a sign of a void in the ground below it," said Buzz Scher, a retired geotechnical engineer. "A very large depression, where ground failure occurs very quickly, could be settlement, cracking, spreading."

U.S Geological Survey describes sinkholes as "closed natural depression in the ground surface caused by removal of material below the ground and either collapse or gradual subsidence of the surface into the resulting void."

Potholes, meanwhile, are generally much smaller and caused mostly by failure of paving materials.

Still, small or not, scientifically a sinkhole or not, incidents like one in April in which a woman tipped her car over a pothole can be scary. And following the November 30 earthquake, it's far from unlikely that damages to roadways won't continue to spring up as the snow stays aware.

"With the recent earthquake, we saw some subsidence and some ground failure - collapse, if you will," said John Thornley, a geotechnical engineer currently practicing. "And if you think about the ground and soil, you have all these little particles, gravel, sand, silt, and if those are really tight together and the earth starts shaking, they get closer and closer together."

Home and business owners, city and state maintenance teams, and others will be staying on the lookout.

"Depending on what profession you're talking to - engineers versus geologists, road maintenance crews, DOT - when a large pothole opens up because of a pipe and there's a hole, it's a sinkhole," Scher said."The ground has sunk into it."

To report potholes within the Municipality of Anchorage, you can contact the Street Maintenance Department at 343-MEND (6363).