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Enviroscan Ukrainian Institute of Speleology and Karstology


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Community news

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That alkalinity is the property of water to neutralize acids. usually expressed in terms of calcium carbonate equivalents [16]. see also acidity; ph.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for sinkholes, (Keyword) returned 70 results for the whole karstbase:
Showing 1 to 15 of 70
Karst development in Ordovician carbonates: Western Platform of Newfoundland, Master of Science (MS) Thesis, 1978,
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Karolyi, Marika Sarolta

The Appalachian fold belt system in Newfoundland is divided into three tectonic divisions: Western Platform; Central Mobile Belt; Avalon Platform Rocks of the Western Platform range in age from Precambrian to Carboniferous. Major karst areas are found there is Ordovician and Carboniferous rocks. Karst features of the study area (Goose Arm to Bonne Bay Big Pond) are in the Ordovician carbonates of the undivided St. George and Table Head Formations, covering a few hundred square kilometers. Features include karren, sinkholes, sinking streams, and karst springs, caves and other solutional and collapse features.
In the study area multiple fold and faulting episodes complicate the geology. Extensive and probably repeated glaciations have produced rugged terrane with U-shaped valleys and as much as 300m relief on the carbonates. There is variable but thick till cover. A class or classes of ice-scoured closed depressions with internal drainage are recognized. Postglacial karst forms are limited to varieties of karren (mainly littoral), small sinkholes, and cave systems that are inaccessively small in most instances. Distribution of all karst features is highly irregular.
Hydrologic patterns follow fluvial, fluviokarstic and holokarstic drainage. Large number of sinking ponds have seasonal overflow channels. The ground water drainage routes are generally short and shallow, with varied hydraulic gradients. Few instances of ground water route integration to regional springs is found.
The water chemistry of the area displays a tight normal distribution of hardness. This is attributed to the ponding effect. Seasonal trends show an overall increase in total hardness and other parameters, with some ponds showing linear increases and others cyclic variations.
Karst type and distribution is complex and irregular, but both glaciokarstic and karstiglacial development is present. The majority of karst forms point to karstiglacial development where previous karst forms have been modified by ice. Karstification is controlled by geology, rock lithology, hydraulic gradients and glacial scour and infill. Karstic processes continue to operate today, modifying the scoured basins and creating new karst forms.


Classification of Pseudokarst forms in Czechoslovakia., 1983,
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Vitek Jan
The paper is a geomorphological classification of pseudokarst forms in Czechoslovakia/Bohemien Massif and the Carpathians. In the author's opinion, forms occurring in non-carbonate rocks, are morphologically and often genetically analogous to the forms of karst relief, and are pseudokarst phenomena. They are divided according to their size into macroforms in sandstone morphostructures of the Bohemian Cretaceous Basin some types of rocky valleys, water-shed plains and ridges, forming rock cities in some places, mesoforms with six types of caves, sinkholes, rock perforations and several rock phenomena and microforms such as weather pits and niches, lapies, etc.. The most prominent pseudokarst phenomena have been formed in the sandstones of the Bohemian Cretaceous Basin whose relief may be considered "pseudokarst". They are also common in other sediments; in neovolcanic rocks and granitic rocks, as well as in other types of rocks. Pseudokarst forms are the product of geomorphological processes, especially weathering and denudation, block rock slides, erosion, suffosion, etc. Most of them have been developing in the recent mild humid climatic conditions.

Un pseudo-karst dans les argiles (Las Bardenas, Navarre, Espagne), 1986,
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Maire R. , Pernette J. F.
PSEUDO-KARST IN SANDY-CLAY (LAS BARDENAS NAVARRA-, SPAIN) - The spectacular badlands of Las Bardenas are situated south of the Navarra province (NE Spain); they develop in the sandy-clay (Oligo-Miocene) of the tertiary Ebra basin, with a semi-arid climatic context (<400 mm/year). Pseudo-karstic landforms have been observed near mini-canyons: sinkholes, pits, caves, natural bridges... This morphology of mechanical origin is possible because the running waters disappear underground into the decompression fissures generated on the edges of canyon cliffs. Yet, in a few caves, the gallery is made directly in the mass of sandy-clay, without the help of joints, cracks or fissures ("piping"). This recent pseudo-karst and badlands are the obvious consequence of the historical destruction of forest during the Middle Age.

HYDROLOGIC RESPONSE OF A KARST WATERSHED, 1994,
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Felton Gk,
A ground water catchment was instrumented as a karst hydrology and water quality laboratory to develop long-term flow and water quality data. This catchment located in Woodford and Jessamine Counties in the Inner Bluegrass, Central Kentucky encompasses approximately 1620 ha, 40 water wells, over 400 sinkholes, 2 karst windows, and 1 sinking stream. The land uses consist of approximately 59% beef pasture, horse farm, and golf course; 16% row crops; 6% orchard; 13%forest; and 6% residential. The instrumentation consisted of a recording rain gage, an H-flume, a water stage recorder, and an automated water sampler. Flow data for 312 days were analyzed, and a peak flow rate prediction equation, specific to this catchment, was developed Recession curves were analyzed and found to be of two distinct mathematical forms, log curves and exponential curves. Prediction equations were good for the log-type recession curve and fair for the exponential-type recession curve. For the exponential recessions, the peak flow rate was found to be bimodally distributed The recession events were classified as either high flow or low flow, with the point of separation at 113 L/s. It was hypothesized that the flow system was controlled by pipe flow above 113 L/s and by open channel flow below 113 L/s. Subsequent analysis resulted in adequate prediction for the low flow events. Explained variation associated with the high flow events was low and attributed to storage in the karst system that was not incorporated into the predictor equation

THE KASKASKIA PALEOKARST OF THE NORTHERN ROCKY-MOUNTAINS AND BLACK-HILLS, NORTHWESTERN USA, 1995,
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Palmer A. N. , Palmer M. V. ,
The Kaskaskia paleokarst, part of the Mississippian-Pennsylvanian unconformity in North America, is typified by sinkholes, fissures, and dissolution caves at and near the top of the Kaskaskia Sequence (Madison Limestone and equivalents) and is covered by basal Absaroka siliciclastics (Chesterian to Morrowan). In the Rocky Mountains and Black Hills of the northwestern U. S. A. it postdates earlier features produced by sulfate-carbonate interactions, including breccias, dissolution voids, bedrock alteration, and mineralization. Both the paleokarst and earlier features have been intersected by post-Laramide caves. Ore deposits, aquifers, and petroleum reservoirs in the region are also concentrated along both the paleokarst horizons and earlier sulfate-related features. Each phase of karst modified and preferentially followed the zones of porosity and structural weakness left by earlier phases, producing an interrelated complex of now-relict features. All should be considered together to explain the present aspect of the paleokarst

Gypsum karst in the United States., 1996,
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Johnson Kenneth S.
Gypsum is one of the most soluble of common rocks; it is dissolved readily to form caves, sinkholes, disappearing streams, and other karst features that typically are found in limestones and dolomites. The four basic requirements for gypsum karst to develop are: (1) a deposit of gypsum; (2) water, unsaturated with CaSO4 (3) an outlet for escape of dissolving water; and (4) energy to cause water to flow through the system. Gypsum deposits are present in 32 of the 48 conterminous United States, and they underlie about 35-40% of the land area; they are reported in rocks of every geologic system from the Precambrian through the Quaternary. Gypsum karst is known at least locally (and sometimes quite extensively) in almost all areas underlain by gypsum, and commonly extends down to depths of at least 30 m below the land surface. The most widespread and pronounced examples of gypsum karst are in the Permian basin of southwestern United States, but many other areas also are significant. Human activities may also cause, or accelerate, development of gypsum karst.

Gypsum karst of the Baltic republics., 1996,
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Narbutas Vytautas, Paukstys Bernardas
The Baltic Republics of Estonia, Latvia and Lithuania have karst areas developed in both carbonate and gypsiferous rocks. In the north, within the Republic of Estonia, Ordovician and Silurian limestones and dolomites crop out, or are covered by glacial Quaternary sediments. To the south, in Latvia and Lithuania, gypsum karst is actively developing in evaporites of Late Devonian (Frasnian) age. Although gypsum and mixed sulphate-carbonate karst only occupy small areas in the Baltic countries, they have important engineering and geo-ecological consequences. Due to the rapid dissolution of gypsum, the evolution of gypsum karst causes not only geological hazards such as subsidence, but it also has a highly adverse effect on groundwater quality. The karst territory of the Baltic states lies along the western side of the area, called the Great Devonian Field that form part of the Russian Plain. Within southern Latvia and northern Lithuania there is an area, exceeding 1000 sq. km, where mature gypsum karst occurs at the land surface and in the subsurface. This karst area is referred to here as the Gypsum Karst Region of the Baltic States. Here the surface karst forms include sinkholes, karst shafts, land subsidence, lakes and dolines. In Lithuania the maximum density of sinkholes is 200 per sq. km; in Latvia they reach 138 units per sq. km. Caves, enlarged dissolution voids and cavities are uncommon in both areas.

Evaporite karst in the United States, 1997,
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Johnson K. S. ,
Evaporites, including gypsum (or anhydrite) and salt, are the most soluble of common rocks; they are dissolved readily to form caves, sinkholes, disappearing streams, and other karst features that typically are found in limestones and dolomites. The four basic requirements for evaporite karst to develop are: (1) a deposit of gypsum or salt; (2) water, unsaturated with CaSO4 or NaCl; (3) an outlet for escape of dissolving water; and(4) energy to cause water to now through the system Evaporites are present in 32 of the 48 contiguous states, and they underlie about 35-40% of the land area; they are reported in rocks of every geologic system from the Precambrian through the Quatemary. Evaporite karst is known at least locally (and sometimes quite extensively) in almost all areas underlain by evaporites. The most widespread and pronounced examples of both gypsum and salt karst are in the Permian basin of the southwestern United States, but many other areas are also significant. Human activities have caused some evaporite-karst development, primarily in salt deposits. Boreholes may enable (either intentionally or inadvertently) unsaturated water to now through or against salt deposits, thus allowing development of small to large dissolution cavities. If the dissolution cavity is large enough and shallow enough, successive roof failures above the cavity can cause land subsidence or catastrophic collapse

Sinkholes, soils, fractures, and drainage: Interstate 70 near Frederick, Maryland, 1997,
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Boyer Bw,
Numerous sinkholes have recently formed on both sides of Interstate 70 south of Frederick, Maryland, All the sinkholes are cover-collapse types, which form when soil cavities grow upward from the bedrock surface until their roofs become unstable, Areas at greatest risk for sinkhole development lie within a network of dry swales, The roughly dendritic map pattern and presence of allochthonous siliciclastic alluvium suggest that these swales are the vestiges of a vanished surface drainage system. Sinkholes occur mainly along bedrock escarpments underlying the swales, which are located along an easterly-trending transverse fracture and a series of strike-parallel fractures which intersect with it. Although the surface drainage appears to have Bowed east and north in the past, surface runoff in large quantities is infiltrating the ground or directly entering some of the sinkholes, then following subsurface conduits which convey it southward under the highway. Compaction grouting has been employed to prevent collapse or further subsidence of the most threatened portions of the highway. Soil Survey maps can be useful in locating cryptic intermittent or relict drainage pathways which may be at high risk for sinkhole formation when subjected to anthropogenic concentrations of perched storm water

Role of public awareness in groundwater protection, 1997,
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Ekmekci M, Gunay G,
Scarcity of water, particularly in towns situated along the Mediterranean coast where the main aquifers are in karstic carbonate rocks, necessitates more thoroughness in exploiting and protecting the groundwater resources. Geomorphological and hydrogeological studies have revealed large quantities of the input and throughput features, such as sinkholes, dolines, uvalas and poljes in the recharge areas of many karst aquifers in Turkey. Naturally, recharge areas are generally located at higher elevations and regions remote from the urbanized areas. These features lead the local authorities and persons to utilize the karst features for their own purposes. Dolines and ponors are commonly utilized as injection points for wastewater, while uvalas and poljes are used as solid waste disposal sites. When doing this, the people are unconscious of the connection of such sites with the wells or springs that provide water for their supply. A number of occurrences in Turkey have demonstrated that, no matter how perfect the efficiency of the technical work, protection of the water resources-is primarily related to the consciousness of the local authorities. They must either take proper measures to protect the resources or to educate the public in this issue. To achieve this aim, it is very important to involve the public administrative sector and the technical sector in preparing guidelines for integrated environmental evaluation of karst water resources. The main phase of a study should include locating appropriate sites for disposal of wastewater and various liquid and solid wastes that will satisfy requirements by the administrators as well as providing a water supply of good quality for the public. This paper discusses the issue of how to overcome the public awareness problem. Some examples demonstrate how the technical, achievements failed to be effective and applicable due to the lack of contribution on the part of the local authorities and the public. Some suggestions are made concerning a revision of the currently insufficient regulations

Comparison of stormwater management in a karst terrane in Springfield, Missouri - case histories, 1999,
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Barner Wl,
Control of stormwater in sinkhole areas of Springfield, MO has involved the utilization of several standard approaches: concrete-lined channels draining into sinkholes; installation of drainage pipes into the sinkhole 'eyes' (swallow holes); filling of sinkholes; elaborate drains or pumps to remove stormwater from one sinkhole and discharging into another drainage basin or sinkhole; and enlargement of swallow holes by excavation to increase drainage capacity. Past planning considerations and standard engineering approaches have resulted in flooding of sinkholes and drainage areas, including residential, industrial and commercial developments. Having recognized the inadequacy of existing designs to control flooding and the need to accommodate increased runoff from future development, the City of Springfield adopted an ordinance (effective 19 June 1989 and modified in 1990 and 1993) in response to public pressure and concerns over flooding in sinkholes and sinkhole drainage areas. Three sites were analyzed to examine the effectiveness of contrasting design approaches to stormwater management. These sites differ in vegetation, on-site/off-site considerations, and types of development proposed. All three sites are located within the East Cherry Street Sinkhole Area. The first site, a wooded tract with unmodified sinkholes was cleared and developed for residential use. Discharge of stormwater was directed into sinkholes, and erosion control consisted of hydro-mulching and sedimentation fences in sinkhole areas. East of this location are two parcels which differ in removal of vegetation and off-site drainage relationships. Stormwater design in these sites was adapted for modifications made to sinkholes during railroad and highway construction several decades earlier. Sediment fencing, hydro-mulching and detention berms augment infiltration, restrict erosion, retard discharge to sinkholes, and incorporate off-site considerations. Ongoing observations of stormwater behavior indicate problems of flooding and sediment control at the western site but minimal disruptions of existing drainage patterns at the eastern sites. Design calculation for the western site show adequate volume retention in sinkholes, but different design approaches were implemented to 'soften' the impact of stormwater discharging into these sinkholes, allowing for minimal disruptions in the natural drainage network. The lack of recognition of sinkholes as integral parts of dynamic hydrologic systems may result in problems with on-site/off-site drainage. Standard engineering designs for stormwater detention are not appropriate for the hydraulic characteristics of the shallow karst drainage network. While runoff estimations are conservative, the design calculations fall short of adequately addressing actual stormwater runoff characteristics. (C) 1999 Elsevier Science B.V. All rights reserved

A four-component mixing model for water in a karst terrain in south-central Indiana, USA. Using solute concentration and stable isotopes as tracers, 2001,
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Lee E. S. , Krothe N. C. ,
The study area lies in a highly karstified carbonate terrain in south central Indiana. Sinkholes, conduits, and caves form large secondary pathways for the subsurface flow. As a result, the discharge from a main emergence point for the subsurface flow system, the Orangeville Rise, quickly responds to the storm events and shows wide variations in flow rate, water chemistry, and stable isotopic compositions. These responses are attributed to the mixing of water in secondary pathways. In the study area, recharge occurs through the thick, mantled karst plain and the sinkhole plains, and the role of soil layer and epikarst in the recharge process is of great importance. Rain (DIC: 2 HCO3- mg/l, delta C-13 (DIC): - 7%o) soil water (DIC: 544 HCO3- mg/l, delta C-13(DIC): - 14.7%o), epikarstic water (DIC: 224 HCO3- mg/l delta C-13(DIC): - 13.6%o), and phreatic diffuse flow water (DIC: 299 HCO3- mg/l, delta C-13(DIC): - 11.8%o) generally showed unique and constant dissolved inorganic carbon (DIC) and delta C-13(DIC) values over time. Using DIC and delta C-13(DIC) as tracers, a four-component mixing model was established for the karstic flow system. By constructing the discharge hydrograph separation curves, the mixing ratio of each component, rain (10.6%), soil (3.1%), epikarstic (52.3%), and phreatic (34.0%) water, was determined for the Orangeville Rise discharge over the testing period of 104 h after the storm event of 10/4/90. Vadose water occupied 55.4% of spring discharge and this demonstrates the importance of the unsaturated zone, especially the epikarst, in the karstic flow systems. (C) 2001 Elsevier Science B.V. All rights reserved

Geological barrier - a natural rock stratum for preventing confined karst water from flowing into mines in North China, 2001,
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Zhou W. F. , Li G. Y. ,
Coalfields in North China encompassing than ten Provinces contain six to seven coal seams in the Permo-Carboniferous strata. The lower three seams, accounting for 37% of the total reserves , are threatened with karst water from the underlain Ordovician limestone. Hundreds of water inrush incidences have occurred in which a large amount of water suddenly flows into tunnels or working faces under high potentiometric pressure 20 years. Large-scale dewatering or depressurizing of the karst aquifer was considered essential to water inrushes and keep the mines safely operational. This practice has caused sinkholes, dry gs, water supply shortage, and groundwater Keywords Geological barrier contamination in the surrounding areas, which is environmentally not permitted. One of the alternative water control measures is to make full use of the layer between the coal seam and the karst er as a geological barrier. Similar to the application in the nuclear industry where a geological barrier of this application is considered a hydraulic barrier as well with the objective to prevent or constrain water flow from the underlying aquifer into mines. Its effectiveness to constrain water flow is described by a parameter referred to as hydrofracturing pressure (P-hf) When the water pressure in the underlying aquifer exceeds P-hf, a wedging effect takes place within the fractures of the geological barrier and, as a result, water inrush occurs. In-situ hydrofracturing tests were used to determine P-hf in bauxite and silty sandstone at tunnels. The P-hf in the silty sandstone is larger than that in the bauxite but they both vary with depth (distance from the bottom of the tunnel). Based on the test results, a new safety criterion for water inrush was derived for mines and it has been successfully applied to mining practices with the minium effort of dewatering in the karst aquifer. The same criterion can also be applied to tunneling and quarrying in areas with similar geological conditions

Contaminant transport in karst aquifers., 2001,
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Vesper D. J. , Loop C. M. , White W. B.
Contaminants are easily injected into karst aquifers through sinking streams, sinkholes, or through open fractures and shafts in the carbonate rock. Transport of the contaminants through the aquifer is by a variety of mechanisms depending on the physical and chemical properties of the contaminant. Contaminants consist of (1) water soluble compounds, both organic and inorganic, (2) slightly soluble organic compounds, less dense than water (LNAPLs), (3) slightly soluble organic compounds, more dense than water (DNAPLs), (4) pathogens, (5) metals, and (6) trash. Water soluble compounds (e.g. nitrates, cyanides, carboxylic acids, phenols) move with the water. But rather than forming a plume spreading from the input point, the contaminated water forms linear stringers migrating down the conduit system toward the discharge point. LNAPLs (e.g. petroleum hydrocarbons) float on the water table and can migrate down the water table gradient to cave streams where they tend to pond behind obstructions. DNAPLs (e.g. chlorinated hydrocarbons), in contrast, sink to the bottom of the aquifer. In the conduit system, DNAPLs pond in low spots at the bottom of the conduit and infiltrate sediment piles. Transport of both LNAPL and DNAPL is dependent on storm flow which can force LNAPL through the system as plug flow and can move DNAPLs by mobilizing the sediment piles. Pathogens (viruses, bacteria, parasites) are transported through the karstic drainage system because of the absence of filtration and retain their activity for long distances. Metals (e.g. chromium, nickel, cadmium, mercury, and lead) tend to precipitate as hydroxides and carbonates in the neutral pH, carbonate rich water of the karst aquifer. Metal transport is mainly as particulates and as metal adsorbed onto small particulates such as clays and colloids. Metal transport is also episodic. Metals migrate down the flow path under flow conditions that take small particulates into suspension. Trash is carried into karst aquifers through sinkholes and sinking streams. It is, in effect, a form of clastic sediment, and can be carried deep into the conduit system where it can act as a source term for other contaminants leached from the trash.

Karst in evaporite rocks of the United States., 2001,
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Johnson K. S.
Evaporites are the most soluble of common rocks; they are dissolved readily to form the same range of karst features that typically are found in limestones and dolomites. Evaporites, including gypsum (or anhydrite) and salt, are present in 32 of the 48 contiguous United States, and they underlie about 35-40% of the land area. Evaporite outcrops typically contain sinkholes, caves, disappearing streams, and springs. Other evidence of active karst in evaporites includes surface-collapse features and saline springs or saline plumes that result from dissolution of salt. Many evaporites, including some in the deeper subsurface, also contain evidence of paleokarst that is no longer active; this evidence includes dissolution breccias, breccia pipes, slumped beds, and collapse structures. Evaporites occur in 24 separate structural basins or geographic districts in the United States, and either local or extensive evaporite karst is known in almost all of these basins or districts. Human activities also have caused development of evaporite karst, primarily in salt deposits. Boreholes or underground mines may enable (either intentionally or inadvertently) unsaturated water to flow through or against salt deposits, thus allowing development of small to large dissolution cavities. If the dissolution cavity is large enough and shallow enough, successive roof failures can cause land subsidence or catastrophic, collapse. Evaporite karst, both natural and human-induced, is far more prevalent than commonly believed.

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