The 3 Major Types of Sinkholes in Florida
What is a sinkhole?
A sinkhole is an area of ground that no natural external surface drainage - when it rains, the water stays inside the sinkhole and typically drains into the subsurface. Sinkholes can vary from a few feet to hundreds of acres and from less than 1 feet to more than 100 feet deep. Some are shaped like shallow bowls or saucers whereas others have vertical walls; some hole water and form natural ponds.
Typically, sinkholes form so slowly that little change is noticeable, but they can form suddenly when a collapse occurs. Such a collapse can have a dramatic effect if it occurs in an urban setting. Many of central and north Florida's lakes are actually a result of old sinkholes.
What are the types of sinkholes?
Since Florida is prone to sinkholes, it is necessary to discuss some different types of sinkholes and the geological and hydrological processes that form from them. The process of dissolution, where surface rock that are soluble to weak acids are dissolved and suffusion, where cavities form below the land surface, are responsible for virtually all sinkholes in Florida.
Solution or Dissolution Sinkholes :
Form where water dissolved limestone under a soil covering. Dissolution enlarges natural openings in the rock such as joints, fractures, and bedding planes. Soil settles down into the enlarged openings forming a small depression at the ground surface.
Cover-subsidence Sinkholes :
Cover-subsidence sinkholes form where voids in the underlying limestone allow for more setting of the soil to create larger surface depressions.
Cover-collapse Sinkholes :
Cover-collapse sinkholes or "dropouts: form where so much soil settles down into the voids in the limestone that the ground surface collapses. The surface collapse can also form when man changes the natural water drainage in karst areas.
What are some sinkhole warning signs?
A rapid sinkhole caused by well drilling or other sudden alterations to the terrain may not give any warning signs. Otherwise the collapse process usually occurs gradually enough that a person may leave that affected area safely. The final breakthrough can develop over a period of a few minutes to a few hours.
Some warning signs of naturally occurring sinkholes include :
Leaning fences or trees
Cracks in structures over a forming sinkhole
Suspicious dying of plants and vegetations
Doors and windows not closing properly
There are many other causes of localized ground settlement and vegetation stress, and depressed areas are not necessarily indications of an imminent sinkhole. For all sinkhole repair needs, from a diagnosis to actual repair, Cloud 9 Services, Inc. is there for you.