JACKSONVILLE, Fla. -- In Florida, residents don't have to worry about volcanoes or massive landslides.
Earthquakes, while possible, are quite rare.
Our major geologic threats are sinkholes.
Florida has the largest concentration of sinkholes in the United States.
According to the Florida Geological Survey (FGS), sinkholes cause millions of dollars in damage each year to public property, highways and private homes.
The business of sinkhole detection and prevention is booming here in Florida because of the looming threat.
"The limestone in Florida is very young, is very weak, and is easily weathered," UNF associate professor of civil engineering Dr. Nick Hudyma said.
He said when a limestone deposit recedes, the layers of rock and soil above go down with it.
"It's much like a sand hourglass," Hudyma added.
Florida's underground structure makes it more prone to the sinkholes forming than in any other part of the country.
Not all limestone in Florida is created equal.
The layers above the limestone base in Northern Florida are much thicker than other regions in Florida, Hudyma said.
"Of course, there is always the possibility of sinkholes forming in Duval, but historically they are not happening here," he said.
According to a map produced by the Florida Geological Survey, there are three major areas for potential sinkhole formation in Duval County.
Two of the areas are not residential.
However, one of the areas on the sinkhole map is located directly under an apartment building on Jacksonville's Northside.
Dr. Hudyma said the Northside sinkhole is nothing to be concerned about.
"Those maps should come with a disclaimer at the bottom that says 'these may not be natural sinkholes," Hudyma said.
He believes some local sinkholes could be caused by underground pipes leaking, or another man made situation.
He says small sinkholes may develop in people's yards -- as we saw earlier in April here -- and while those can present problems, he says they shouldn't be catastrophic like the ones that occur in Central and Western Florida.
"We can never say it's impossible, but it's very unlikely," Hudyma said.
Limestone layers in Central and West Florida are significantly thinner than the layers in Northern Florida, Hudyma said.
Still, it's always helpful to be prepared for a sinkhole, whether big or small.
Hudyma said the first thing you should do if you suspect one on your property is to call a geotechnical engineer.
FGS also suggested calling your homeowners insurance company to let them know.
If you notice a sinkhole on public property, like a road or sidewalk, FGS says you should call the city or county agency responsible for the property.
Here's a link to all the information you may need when it comes to sinkholes.
First Coast News