What is a sinkhole?
A sinkhole is a depression in the ground that has no natural external surface drainage. Basically, this means that when it rains, all of the water stays inside the sinkhole and typically drains into the subsurface.
Sinkholes are most common in what geologists call, “karst terrain.” These are regions where the types of rock below the land surface can naturally be dissolved by groundwater circulating through them. Soluble rocks include salt beds and domes, gypsum, and limestone and other carbonate rock. Florida, for instance, is an area largely underlain by limestone and is highly susceptible to sinkholes.
When water from rainfall moves down through the soil, these types of rock begin to dissolve. This creates underground spaces and caverns.
Sinkholes are dramatic because the land usually stays intact for a period of time until the underground spaces just get too big. If there is not enough support for the land above the spaces, then a sudden collapse of the land surface can occur.
Find more information about sinkholes at the USGS Water Science School.
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Effects of projected climate (2011–50) on karst hydrology and species vulnerability—Edwards aquifer, south-central Texas, and Madison aquifer, western South Dakota
Karst aquifers—formed by the dissolution of soluble rocks such as limestone—are critical groundwater resources in North America, and karst springs, caves, and streams provide habitat for unique flora and fauna. Springflow and groundwater levels in karst terrane can change greatly over short time scales, and therefore are likely to...
Mahler, Barbara; Stamm, John F.; Poteet, Mary F.; Symstad, Amy J.; Musgrove, MaryLynn; Long, Andrew J.; Norton, Parker A.
Karst in the United States: A digital map compilation and database
This report describes new digital maps delineating areas of the United States, including Puerto Rico and the U.S. Virgin Islands, having karst or the potential for development of karst and pseudokarst. These maps show areas underlain by soluble rocks and also by volcanic rocks, sedimentary deposits, and permafrost that have potential for karst or...
Weary, David J.; Doctor, Daniel H.
Sinkholes
Sinkholes are a common feature in Missouri where limestone and dolomite outcrop. Though often considered a benign nuisance, sudden, catastrophic collapses can destroy property, delay construction projects, and contaminate ground water resources.
Kaufmann, James E.
Land subsidence in the United States
No abstract available.
Galloway, Devin L.; Jones, David R.; Ingebritsen, S.E.
Land subsidence in the United States
This report explores the role of science in defining and understanding subsidence problems, and shows that the optimal use of our land and water resources may depend on improved scientific understanding to minimize subsidence. More than 80 percent of the identified land subsidence in the Nation is a consequence of human impact on subsurface water...
Galloway, Devin L.; Jones, David R.; Ingebritsen, S.E.
Karst topography; computer animations and paper model
Alpha, T.R.; Galloway, John P.; Tinsley, J. C.
Geology of caves
A cave is a natural opening in the ground extending beyond the zone of light and large enough to permit the entry of man. Occurring in a wide variety of rock types and caused by widely differing geological processes, caves range in size from single small rooms to intercorinecting passages many miles long. The scientific study of caves is called...
Morgan, I.M.
Development of sinkholes resulting from man's activities in the Eastern United States
Development of induced sinkholes in carbonate terranes in the Eastern United States has resulted in costly damage and water pollution. Previously, detailed investigations of sinkholes were limited to Alabama and Missouri, with the most comprehensive being in Alabama. An investigation of the remainder of the area was made in 1981 to regionalize...
Newton, John G.
Formation of solution-subsidence sinkholes above salt beds
Ege, John R.
EarthWord–Karst
Although it sounds like a Batman punch, this EarthWord is closer to the Bat than you’d think...
Karst landscapes are more prone to have land subsidence and sinkholes.
Map of U.S. showing karst areas, which are prone to land subsidence and sinkholes.
The sudden and sometimes catastrophic subsidence associated with localized collapse of subsurface cavities (sinkholes) is detailed in two case studies. This type of sub-sidence is commonly triggered by ground-water-level declines caused by pumping and by enhanced
...
Karst, Critters, and Climate Change
This webinar was conducted as part of the Climate Change Science and Management Webinar Series, co-hosted by the USGS National Climate Change and Wildlife Science Center and the FWS National Conservation Training Center. Webinar Description: One-half of North American imperiled species live in subterranean habitats, which largely are associated with karst (a type of
An Unseen World Beneath Our Feet - Caves, Sinkholes and Springs
Randall Orndorff, Director of the Eastern Geology and Paleoclimate Science Center, discusses how Karst affects daily life. Beneath a quarter of the United States are rock types that can dissolve to form caves, sinkholes and other features. Nearly every state has rock layers of limestone, gypsum, and other soluble rocks we call ‘karst’. Karst is important for many reasons.
Karst features, Buffalo National River
Examples of karst features within the Buffalo National River Park. Karst is a type of topography that is formed over limestone, dolomite, or gypsum by dissolving or solution, and that is characterized by closed depressions or sinkholes, caves, and underground drainage (American Geological Institute Dictionary of Geologic Terms).
Sinkholes in West-central Florida, Freeze Event of 2010
More than 110 sinkholes formed in the Dover area of Florida during a freeze event in January 2010. Ground water levels dropped to record-setting lows as farmers pumped water to irrigate their plants for protection from the cold temperatures. The sinkholes destroyed homes, roads and sections of cultivated areas.
Sinkholes in West-central Florida, Freeze Event of 2010
Sinkholes affect roadway safety and require constant maintenance and monitoring. More than 110 sinkholes formed in the Dover area of Florida during a freeze event in January 2010. Ground water levels dropped to record-setting lows as farmers pumped water to irrigate their plants for protection from the cold temperatures. The sinkholes destroyed homes, roads and sections of
...
Sinkholes in West-central Florida, Freeze Event of 2010
The entire root perimeter of this tree collapsed in response to subsidence activity. More than 110 sinkholes formed in the Dover area of Florida during a freeze event in January 2010. Ground water levels dropped to record-setting lows as farmers pumped water to irrigate their plants for protection from the cold temperatures. The sinkholes destroyed homes, roads and
...
Sinkholes in West-central Florida, Freeze Event of 2010
More than 110 sinkholes formed in the Dover area of Florida during a freeze event in January 2010. Ground water levels dropped to record-setting lows as farmers pumped water to irrigate their plants for protection from the cold temperatures. The sinkholes destroyed homes, roads and sections of cultivated areas.
Sinkhole Activity Damages Home.
Cracking along exterior walls is a sign of subsidence activity. Such severe structural damage from sinkholes can destroy homes and other structures. More than 110 sinkholes formed in the Dover area of Florida during a freeze event in January 2010. Ground water levels dropped to record-setting lows as farmers pumped water to irrigate their plants for protection from the
...
Sinkholes in West-central Florida, Freeze Event of 2010
More than 110 sinkholes formed in the Dover area of Florida during a freeze event in January 2010. Ground water levels dropped to record-setting lows as farmers pumped water to irrigate their plants for protection from the cold temperatures. The sinkholes destroyed homes, roads and sections of cultivated areas.