HOME

TheInfoList




Karst is a
topography Topography is the study of the forms and features of land surfaces. The topography of an area could refer to the surface forms and features themselves, or a description (especially their depiction in maps). Topography is a field of geoscience ...
formed from the dissolution of soluble rocks such as
limestone Limestone is a common type of carbonate rock, carbonate sedimentary rock. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science), crystal forms of calcium carbonate (). Limestone forms ...

limestone
,
dolomiteDolomite may refer to: *Dolomite (mineral) Dolomite () is an anhydrous A substance is anhydrous if it contains no water. Many processes in chemistry can be impeded by the presence of water; therefore, it is important that water-free reagents and ...
, and
gypsum Gypsum is a soft sulfate mineralThe sulfate minerals are a class of mineral In geology Geology (from the Ancient Greek γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is an Earth science concerned with the ...

gypsum
. It is characterized by underground drainage systems with
sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as vrtače and shakeholes, and to openings ...

sinkhole
s and
cave A cave or cavern is a natural void in the ground Ground may refer to: * Soil, a mixture of clay, sand and organic matter present on the surface of the Earth * Ground (electricity), the reference point in an electrical circuit from which voltag ...

cave
s. It has also been documented for more
weathering Weathering is the deterioration of rocks A rock is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its Chemical compound, chemical composition and the way in wh ...
-resistant rocks, such as
quartzite Quartzite is a hard, non- foliated metamorphic rock which was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tecto ...

quartzite
, given the right conditions. Subterranean drainage may limit surface water, with few to no rivers or lakes. However, in regions where the dissolved bedrock is covered (perhaps by debris) or confined by one or more superimposed non-soluble rock strata, distinctive karst features may occur only at subsurface levels and can be totally missing above ground. The study of ''paleokarst'' (buried karst in the
stratigraphic column A stratigraphic column is a representation used in geology Geology (from the Ancient Greek γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is an Earth science concerned with the solid Earth, the rock (geology), ...
) is important in
petroleum geology Petroleum geology is the study of origin, occurrence, movement, accumulation, and exploration of hydrocarbon fuels. It refers to the specific set of geological disciplines that are applied to the search for hydrocarbons (oil exploration). Sediment ...
because as much as 50% of the world's
hydrocarbon reserves Oil reserves denote the amount of petroleum, crude oil that can be technically recovered at a cost that is financially feasible at the present price of oil. Hence reserves will change with the price, unlike oil resources, which include all oil tha ...
are hosted in
carbonate rock 250px, Carbonate ooids on the surface of a limestone; Carmel Formation (Middle Jurassic) of southern Utah, USA. Largest is 1.0 mm in diameter. Carbonate rocks are a class of sedimentary rocks composed primarily of carbonate minerals. The two major ...
, and much of this is found in porous karst systems.


Etymology

The English word ''karst'' was borrowed from German in the late 19th century, which entered German much earlier. According to one interpretation the term is derived from the German name for a number of geological, geomorphological, and hydrological features found within the
range Range may refer to: Geography * Range (geographic)A range, in geography, is a chain of hill A hill is a landform A landform is a natural or artificial feature of the solid surface of the Earth or other planetary body. Landforms together ...
of the
Dinaric Alps The Dinaric Alps (), also commonly Dinarides, are a mountain range in Southern The name Southern may refer to: * South South is one of the cardinal directions or compass points. South is the opposite of north and is perpendicular to the east a ...

Dinaric Alps
, stretching from the northeastern corner of
Italy Italy ( it, Italia ), officially the Italian Republic ( it, Repubblica Italiana, links=no ), is a country consisting of delimited by the and surrounding it, whose territory largely coincides with the . Italy is located in the centre of th ...

Italy
above the city of
Trieste Trieste ( , ; sl, Trst ; german: Triest ) is a city and seaport in northeastern Italy. It is the capital city, and largest city, of the Regions of Italy#Autonomous regions with special statute, autonomous region of Friuli Venezia Giulia, one of t ...

Trieste
, across the
Balkan peninsula The Balkans ( ), also known as the Balkan Peninsula, are a geographic area in southeastern Europe Europe is a continent A continent is one of several large landmasses. Generally identified by convention (norm), convention rather ...

Balkan peninsula
along the coast of the eastern
Adriatic The Adriatic Sea () is a body of water separating the Italian Peninsula from the Balkans. The Adriatic is the northernmost arm of the Mediterranean Sea, extending from the Strait of Otranto (where it connects to the Ionian Sea) to the northwest a ...

Adriatic
to
Kosovo Kosovo, or ; sr-Cyrl, Косово officially the Republic of Kosovo,; sr, / is a international recognition of Kosovo, partially recognised state in Southeast Europe. It lies at the centre of the Balkans, occupying an area of , with ...

Kosovo
and
North Macedonia North Macedonia, ; sq, Maqedonia e Veriut, (Macedonia before February 2019), officially the Republic of North Macedonia,, is a country in Southeast Europe Southeast Europe or Southeastern Europe () is a geographical region of Europe ...
, where the ''massif'' of the
Šar Mountains The Šar Mountains ( Macedonian and Serbian: Шар Планина, ''Šar Planina'') or Sharr Mountains ( sq, Malet e Sharrit), form a mountain range in the Balkans The Balkans ( ), also known as the Balkan Peninsula, are a geographic ...

Šar Mountains
begins, and more specifically the karst zone at the northwesternmost section, described in early topographical research as a
plateau In geology Geology (from the Ancient Greek γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is an Earth science concerned with the solid Earth, the rock (geology), rocks of which it is composed, and the proces ...
, between Italy and
Slovenia Slovenia ( ; sl, Slovenija ), officially the Republic of Slovenia (Slovene: , abbr.: ''RS''), is a country in Central Europe. It is bordered by Italy Italy ( it, Italia ), officially the Italian Republic ( it, Repubblica Italiana, lin ...

Slovenia
. In the local
South Slavic languages The South Slavic languages are one of three branches of the Slavic languages. There are approximately 30 million speakers, mainly in the Balkans. These are separated geographically from speakers of the other two Slavic branches (West Slavic lang ...
, all variations of the word are derived from a Romanized Illyrian base (yielding la, carsus, dlm, carsus), later metathesized from the reconstructed form into forms such as sl, kras and sh, krš, kras. Languages preserving the older, non-metathesized form include it, Carso, german: Karst, and al, karsti; the lack of metathesis precludes borrowing from any of the South Slavic languages, specifically
Slovene Slovene or Slovenian may refer to: * Something of, from, or related to Slovenia, a country in Central Europe * Slovene language, a South Slavic language mainly spoken in Slovenia * Slovenes, an ethno-linguistic group mainly living in Slovenia * Sla ...
. The Slovene common noun was first attested in the 18th century, and the adjective form in the 16th century. As a proper noun, the Slovene form was first attested in 1177.Bezlaj, France (ed.). 1982. , vol. 2, K–O. Ljubljana: SAZU, p. 82. Ultimately, the word is of Mediterranean origin. It has been suggested that the word may derive from the
Proto-Indo-European Proto-Indo-European (PIE) is the theorized common ancestor of the Indo-European language family The Indo-European languages are a language family A language is a structured system of communication used by humans, including speech ( ...
root ' 'rock'. The name may also be connected to the oronym ''Kar(u)sádios oros'' cited by
Ptolemy Claudius Ptolemy (; grc-koi, Κλαύδιος Πτολεμαῖος, , ; la, Claudius Ptolemaeus; AD) was a mathematician A mathematician is someone who uses an extensive knowledge of mathematics Mathematics (from Ancient Greek, Greek ...
, and perhaps also to Latin .


Early studies

Johann Weikhard von Valvasor Valvasor's map of Kingdom of Croatia (Habsburg), Croatia (1689) Johann Weikhard Freiherr von Valvasor or Johann Weichard Freiherr von Valvasor ( sl, Janez Vajkard Valvasor, ) or simply Valvasor (baptised on 28 May 1641 – September or Octob ...
, a pioneer of the study of karst in
Slovenia Slovenia ( ; sl, Slovenija ), officially the Republic of Slovenia (Slovene: , abbr.: ''RS''), is a country in Central Europe. It is bordered by Italy Italy ( it, Italia ), officially the Italian Republic ( it, Repubblica Italiana, lin ...

Slovenia
and a fellow of the Royal Society for Improving Natural Knowledge,
London London is the and of and the . It stands on the in south-east England at the head of a down to the , and has been a major settlement for two millennia. The , its ancient core and financial centre, was founded by the as ' and retains b ...

London
, introduced the word ''karst'' to European scholars in 1689, describing the phenomenon of underground flows of rivers in his account of
Lake Cerknica Lake Cerknica (; sl, Cerkniško jezero, german: Zirknitzer See) is an intermittent lake in the southern part of the Cerknica Polje, a karst Karst is a topography formed from the dissolution of soluble rocks such as limestone Limestone ...
.
Jovan Cvijić Jovan Cvijić ( sr-cyr, Јован Цвијић, ; 12 October 1865 – 16 January 1927) was a Serbian geographer A geographer is a physical scientist, social scientist and humanist whose area of study is geography, the study of Earth' ...

Jovan Cvijić
greatly advanced the knowledge of karst regions, so much that he became known as the "father of karst geomorphology". Primarily discussing the karstic regions of the Balkans, Cvijić's 1893 publication ''Das Karstphänomen'' describes landforms such as karren, dolines and
polje Image:Livanjsko polje, nejvetsi utvar tohoto druhu na svete (70x40.jpg, Livanjsko Polje in Bosnia (region), Bosnia is the largest polje in the world (Mount Dinara visible in the background). A polje, also karst polje or karst field, is a large fl ...

polje
s. In a 1918 publication, Cvijić proposed a cyclical model for karstic landscape development. Karst
hydrology Hydrology (from Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελλάδα, , ), officially the Hellenic Republic, is a country located in Southeast Europe. Its population is approximately 10.7 mill ...
emerged as a discipline in the late 1950s and early 1960s in France. Previously, the activities of cave explorers, called
speleologist Speleology is the scientific study of caves and other karst features, as well as their make-up, structure, physical properties, history, life forms, and the processes by which they form (speleogenesis) and change over time (speleomorphology). ...
s, had been dismissed as more of a sport than a science, meaning that underground karstic caves and their associated watercourses were, from a scientific perspective, understudied.


Development

Karst is most strongly developed in dense
carbonate rock 250px, Carbonate ooids on the surface of a limestone; Carmel Formation (Middle Jurassic) of southern Utah, USA. Largest is 1.0 mm in diameter. Carbonate rocks are a class of sedimentary rocks composed primarily of carbonate minerals. The two major ...
, such as limestone, that is thinly bedded and highly fractured. Karst is not typically well developed in
chalk Chalk is a soft, white, porous Porosity or void fraction is a measure of the (i.e. "empty") spaces in a , and is a of voids over the total volume, between 0 and 1, or as a between 0% and 100%. Strictly speaking, some tests measure the "acce ...

chalk
, because chalk is highly porous rather than dense, so the flow of groundwater is not concentrated along fractures. Karst is also most strongly developed where the water table is relatively low, such as in uplands with , and where rainfall is moderate to heavy. This contributes to rapid downward movement of groundwater, which promotes dissolution of the bedrock, whereas standing groundwater becomes saturated with carbonate minerals and ceases to dissolve the bedrock.


Chemistry of dissolution

The
carbonic acid In chemistry, carbonic acid is a dibasic acid with the chemical formula A chemical formula is a way of presenting information about the chemical proportions of atom An atom is the smallest unit of ordinary matter In classical ...

carbonic acid
that causes karstic features is formed as rain passes through
Earth's atmosphere File:Atmosphere gas proportions.svg, Composition of Earth's atmosphere by volume, excluding water vapor. Lower pie represents trace gases that together compose about 0.043391% of the atmosphere (0.04402961% at April 2019 concentration ). Number ...

Earth's atmosphere
picking up
carbon dioxide Carbon dioxide (chemical formula A chemical formula is a way of presenting information about the chemical proportions of atom An atom is the smallest unit of ordinary matter In classical physics and general chemistry, matter is ...

carbon dioxide
(CO2), which readily dissolves in the water. Once the rain reaches the ground, it may pass through
soil Surface-water- gley developed in glacial till, Northern Ireland.">Northern_Ireland.html" ;"title="glacial till, Northern Ireland">glacial till, Northern Ireland. Soil is a mixture of organic matter, minerals, gases, liquids, and organisms tha ...

soil
that provides additional CO2 produced by
soil respiration Soil respiration refers to the production of carbon dioxide when soil organisms respire. This includes respiration of plant roots, the rhizosphere, microbes and fauna. Soil respiration is a key ecosystem process that releases carbon from the soil ...
. Some of the dissolved carbon dioxide reacts with the water to form a weak carbonic acid solution, which dissolves
calcium carbonate Calcium carbonate is a chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entity, molecular entities) composed of atoms from more than one chemical element, element held together ...

calcium carbonate
. The primary reaction sequence in limestone dissolution is the following: In very rare conditions, oxidation can play a role. Oxidation played a major role in the formation of ancient
Lechuguilla Cave At , Lechuguilla Cave is the eighth-longest explored cave in the world and the second deepest () in the continental United States. It is most famous for its unusual geology, rare speleothem, formations, and pristine condition. The cave is named f ...
in the US state of
New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe, New Mexico, Santa Fe , LargestCity = Albuquerque, New Mexico, Albuquerque , LargestMetro = Albuquerque metropolitan area, Greater Albuqu ...

New Mexico
and is presently active in the Frasassi Caves of Italy. The oxidation of
sulfide Sulfide (British English British English (BrE) is the standard dialect of the English language English is a West Germanic languages, West Germanic language first spoken in History of Anglo-Saxon England, early medieval England, whi ...

sulfide
s leading to the formation of
sulfuric acid Sulfuric acid ( and the ) or sulphuric acid (), known in antiquity as oil of vitriol, is a composed of the elements , and , with the . It is a colorless, odorless and liquid that is with water. Pure sulfuric acid does not exist naturally ...

sulfuric acid
can also be one of the corrosion factors in karst formation. As
oxygen Oxygen is the chemical element Image:Simple Periodic Table Chart-blocks.svg, 400px, Periodic table, The periodic table of the chemical elements In chemistry, an element is a pure substance consisting only of atoms that all have the same ...

oxygen
(O2)-rich surface waters seep into deep anoxic karst systems, they bring oxygen, which reacts with sulfide present in the system (
pyrite The mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. R ...

pyrite
or
hydrogen sulfide Hydrogen sulfide is a chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entity, molecular entities) composed of atoms from more than one chemical element, element held together by ...

hydrogen sulfide
) to form sulfuric acid (H2SO4). Sulfuric acid then reacts with calcium carbonate, causing increased erosion within the limestone formation. This chain of reactions is: This reaction chain forms
gypsum Gypsum is a soft sulfate mineralThe sulfate minerals are a class of mineral In geology Geology (from the Ancient Greek γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is an Earth science concerned with the ...

gypsum
.


Morphology

The karstification of a landscape may result in a variety of large- or small-scale features both on the surface and beneath. On exposed surfaces, small features may include solution flutes (or rillenkarren), ,
limestone pavement and Pen-y-ghent. Image:Limestone pavement above Malham Cove.jpg, Limestone pavement above Malham Cove A limestone pavement is a natural karst Karst is a topography formed from the dissolution of soluble rocks such as limestone Limest ...
(clints and grikes), collectively called karren or lapiez. Medium-sized surface features may include
sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as vrtače and shakeholes, and to openings ...

sinkhole
s or
cenote A cenote ( or ; ) is a natural pit, or sinkhole A sinkhole, also known as a cenote, sink, sink-hole, swallet, swallow hole, or doline (the different terms for sinkholes are often used interchangeably), is a depression or hole in the groun ...

cenote
s (closed basins), vertical shafts, foibe (inverted funnel shaped sinkholes), disappearing streams, and reappearing
spring Spring(s) may refer to: Common uses * Spring (season), a season of the year * Spring (device), a mechanical device that stores energy * Spring (hydrology), a natural source of water * Spring (mathematics), a geometric surface in the shape of a heli ...
s. Large-scale features may include
limestone pavement and Pen-y-ghent. Image:Limestone pavement above Malham Cove.jpg, Limestone pavement above Malham Cove A limestone pavement is a natural karst Karst is a topography formed from the dissolution of soluble rocks such as limestone Limest ...
s,
polje Image:Livanjsko polje, nejvetsi utvar tohoto druhu na svete (70x40.jpg, Livanjsko Polje in Bosnia (region), Bosnia is the largest polje in the world (Mount Dinara visible in the background). A polje, also karst polje or karst field, is a large fl ...

polje
s, and karst valleys. Mature karst landscapes, where more bedrock has been removed than remains, may result in karst towers, or haystack/eggbox landscapes. Beneath the surface, complex underground drainage systems (such as karst
aquifers An aquifer is an underground layer of water Water is an Inorganic compound, inorganic, Transparency and translucency, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constitue ...
) and extensive
cave A cave or cavern is a natural void in the ground Ground may refer to: * Soil, a mixture of clay, sand and organic matter present on the surface of the Earth * Ground (electricity), the reference point in an electrical circuit from which voltag ...

cave
s and cavern systems may form. Erosion along limestone shores, notably in the
tropics The tropics are the region of Earth Earth is the third planet from the Sun and the only astronomical object known to harbour and support life. 29.2% of Earth's surface is land consisting of continents and islands. The remaining 70.8% i ...

tropics
, produces karst topography that includes a sharp makatea surface above the normal reach of the sea, and undercuts that are mostly the result of biological activity or
bioerosion Bioerosion describes the breakdown of hard ocean substrates – and less often terrestrial substrates – by living organisms. Marine bioerosion can be caused by mollusk Mollusca is the second-largest phylum of invertebrate Inve ...
at or a little above
mean sea level There are several kinds of mean in mathematics Mathematics (from Greek: ) includes the study of such topics as numbers ( and ), formulas and related structures (), shapes and spaces in which they are contained (), and quantities and thei ...
. Some of the most dramatic of these formations can be seen in
Thailand Thailand ( th, ประเทศไทย), historically known as Siam, () officially the Kingdom of Thailand, is a country in Southeast Asia. It is located at the centre of the Mainland Southeast Asia, Indochinese Peninsula, spanning , wi ...

Thailand
's Phangnga Bay and at
Halong BayHalong may refer to: * Ha Long, also known as Hong Gai, the capital city of Quang Ninh Province, Vietnam * Halong Bay, a UNESCO World Heritage site located in Quảng Ninh province, Vietnam * Halong naval base, an Indonesian Navy (previously D ...

Halong Bay
in
Vietnam Vietnam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,, group="n" is a country in Southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia or SEA, is the ...

Vietnam
. Calcium carbonate dissolved into water may precipitate out where the water discharges some of its dissolved carbon dioxide. Rivers which emerge from springs may produce
tufa Tufa is a variety of limestone Limestone is a common type of carbonate rock, carbonate sedimentary rock. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science), crystal forms of c ...
terraces, consisting of layers of calcite deposited over extended periods of time. In caves, a variety of features collectively called
speleothem A speleothem (; from Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελλάδα, , ), officially the Hellenic Republic, is a country located in Southeast Europe. Its population is approximately 10.7 ...
s are formed by deposition of calcium carbonate and other dissolved minerals.


Hydrology

Farming in karst areas must take into account the lack of surface water. The soils may be fertile enough, and rainfall may be adequate, but rainwater quickly moves through the crevices into the ground, sometimes leaving the surface soil parched between rains. A
karst fenster A karst window, also known as a karst fenster, is a geomorphic feature found in karst landscapes where an underground river is visible from the surface within a sinkhole. In this feature, a spring emerges, then the discharge abruptly disappears into ...
(karst window) occurs when an underground stream emerges onto the surface between layers of rock, cascades some distance, and then disappears back down, often into a sinkhole. Rivers in karst areas may disappear underground a number of times and spring up again in different places, usually under a different name (like
Ljubljanica The Ljubljanica (), known in the Middle Ages as the ''Sava'', is a river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases a river flows into the ground and bec ...

Ljubljanica
, the river of seven names). An example of this is the Popo Agie River in
Fremont County, Wyoming Fremont County is a County (United States), county in the U.S. state of Wyoming. As of the 2010 United States Census, the population was 40,123. Its county seat is Lander, Wyoming, Lander. The county was founded in 1884 and is named for John C. Fr ...
. At a site simply named "The Sinks" in Sinks Canyon State Park, the river flows into a cave in a formation known as the Madison Limestone and then rises again down the canyon in a placid pool. A turlough is a unique type of seasonal lake found in Irish karst areas which are formed through the annual welling-up of water from the underground water system.Water supplies from
wells Wells most commonly refers to: * Wells, Somerset, a cathedral city in Somerset, England * Well, an excavation or structure created in the ground * Wells (name) Wells may also refer to: Places ;Canada *Wells, British Columbia ;England * Wells ( ...

wells
in karst topography may be unsafe, as the water may have run unimpeded from a sinkhole in a cattle pasture, through a cave and to the well, bypassing the normal filtering that occurs in a porous aquifer. Karst formations are cavernous and therefore have high rates of permeability, resulting in reduced opportunity for contaminants to be filtered.
Groundwater Groundwater is the water Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). It is vital for all known form ...

Groundwater
in karst areas is just as easily as surface streams. Sinkholes have often been used as farmstead or community . Overloaded or malfunctioning
septic tank A septic tank is an underground chamber made of concrete, fiberglass, or plastic through which domestic wastewater (sewage) flows for Sewage treatment, basic treatment. Settling and Anaerobic digestion, anaerobic processes reduce solids and org ...

septic tank
s in karst landscapes may dump raw sewage directly into underground channels. Geologists are concerned with these negative effects of human activity on karst hydrology which, , supplied about 25% of the global demand for drinkable water. The karst topography also poses difficulties for human inhabitants. Sinkholes can develop gradually as surface openings enlarge, but progressive
erosion In earth science Earth science or geoscience includes all fields of natural science Natural science is a branch of science Science (from the Latin word ''scientia'', meaning "knowledge") is a systematic enterprise that Scientific ...

erosion
is frequently unseen until the roof of a cavern suddenly collapses. Such events have swallowed homes, cattle, cars, and farm machinery. In the United States, sudden collapse of such a cavern-sinkhole swallowed part of the collection of the National Corvette Museum in
Bowling Green, Kentucky Bowling Green is a Home rule in the United States, home rule-class city and the county seat of Warren County, Kentucky, United States. Founded by pioneers in 1798, Bowling Green was the provisional capital of Confederate government of Kentucky ...
in 2014.


Interstratal karst

Interstratal karst is a karstic landscape which is developed beneath a cover of insoluble rocks. Typically this will involve a cover of
sandstone Sandstone is a clastic sedimentary rock of a clast (sand grain), derived from a basalt Basalt (, ) is a fine-grained extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron ('' mafic ' ...

sandstone
overlying limestone strata undergoing solution. In the United Kingdom for example extensive doline fields have developed at Cefn yr Ystrad, Mynydd Llangatwg and
Mynydd LlangynidrMynydd Llangynidr is a mountain in the Brecon Beacons National Park largely in the county of Powys, south Wales. Its southern slopes extend into the northernmost parts of the county borough of Blaenau Gwent. It is named from the village of Llangynidr ...
in South
Wales Wales ( cy, Cymru ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by England to the Wales–England border, east, the Irish Sea to the north and west, and the Bristol Channel to the south. It ...

Wales
across a cover of
Twrch Sandstone The Marros Group is the name given to a suite of rocks of Namurian age laid down during the Carboniferous period (geology), Period in South Wales. These rocks were formerly known as the Millstone Grit, Millstone Grit Series but are now distinguished ...
which overlies concealed Carboniferous Limestone, the last-named having been declared a
site of special scientific interest A Site of Special Scientific Interest (SSSI) in Great Britain Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the List ...
in respect of it.


Kegelkarst

Kegelkarst is a type of tropical karst terrain with numerous cone-like hills, formed by cockpits,
mogote A mogote () is a generally-isolated steep-sided residual hill in the tropics composed of either limestone Limestone is a common type of carbonate In chemistry, a carbonate is a salt Salt is a mineral composed primarily of sodium ...
s, and
polje Image:Livanjsko polje, nejvetsi utvar tohoto druhu na svete (70x40.jpg, Livanjsko Polje in Bosnia (region), Bosnia is the largest polje in the world (Mount Dinara visible in the background). A polje, also karst polje or karst field, is a large fl ...

polje
s and without strong fluvial erosion processes. This terrain is found in Cuba, Jamaica, Indonesia, Malaysia, the Philippines, Puerto Rico, southern China, Myanmar, Thailand, Laos and Vietnam.


Pseudokarst

Pseudokarsts are similar in form or appearance to karst features but are created by different mechanisms. Examples include
lava Lava is magma Magma () is the molten or semi-molten natural material from which all s are formed. Magma is found beneath the surface of the , and evidence of has also been discovered on other and some s. Besides molten rock, magma may al ...

lava
caves and
granite Granite () is a coarse-grained (phanerite, phaneritic) intrusive rock, intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cool ...

granite
tors Tors may refer to: * Tor (rock formation) A tor, which is also known by geomorphologists as either a castle koppie or kopje, is a large, free-standing rock outcrop An outcrop or rocky outcrop is a visible exposure of bedrock Bedrock in ...
—for example, Labertouche Cave in
Victoria Victoria most commonly refers to: * Victoria (Australia), a state of the Commonwealth of Australia * Victoria, British Columbia, provincial capital of British Columbia, Canada * Victoria (mythology), Roman goddess of Victory * Victoria, Seychelles ...
,
Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

Australia
—and paleocollapse features. Mud Caves are an example of pseudokarst.


Paleokarst

Paleokarst or palaeokarst is a development of karst observed in geological history and preserved within the rock sequence, effectively a fossil karst. There are for example palaeokarstic surfaces exposed within the Clydach Valley Subgroup of the Carboniferous Limestone sequence of South Wales which developed as sub-aerial
weathering Weathering is the deterioration of rocks A rock is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its Chemical compound, chemical composition and the way in wh ...
of recently formed limestones took place during periods of non-deposition within the early part of the period. Sedimentation resumed and further limestone strata were deposited on an irregular karstic surface, the cycle recurring several times in connection with fluctuating sea levels over prolonged periods.


Karst forest

Karst areas tend to have unique types of forests. The karst terrain is difficult for humans to traverse, so that their ecosystems are often relatively undisturbed. The soil tends to have a high pH, which encourages growth of unusual species of orchids, palms, mangroves and other plants.


Karst areas

The world's largest limestone karst is Australia's Nullarbor Plain. Slovenia has the world's highest risk of sinkholes, while the western Highland Rim in the eastern United States is at the second-highest risk of karst sinkholes. In Canada, Wood Buffalo National Park, NWT contains areas of karst sinkholes. Mexico hosts important karstic regions in the Yucatán Peninsula and Chiapas. The South China Karst in the provinces of Guizhou, Guangxi, and Yunnan provinces is a UNESCO World Heritage Site. The Tham Luang Nang Non karstic cave system in Chiang Rai Province, northern Thailand was made famous by the Tham Luang cave rescue, 2018 rescue of a junior football team.


List of terms for karst-related features

* Abîme, a vertical shaft in karst that may be very deep and usually opens into a network of subterranean passages * Cenote, a deep sinkhole, characteristic of Mexico, resulting from collapse of limestone bedrock that exposes groundwater underneath * Sinkhole, Doline, also sink or sinkhole, is a closed depression draining underground in karst areas. The name "doline" comes from ''dolina'', meaning "valley", and derives from South Slavic languages. * Foibe, an inverted funnel-shaped sinkhole * Karst window (also known as a "karst fenster"), a feature where a spring emerges briefly, with the water discharge then abruptly disappearing into a nearby sinkhole * Karst spring, a spring emerging from karst, originating a flow of water on the surface * Limestone pavement, a landform consisting of a flat, incised surface of exposed limestone that resembles an artificial pavement * Losing stream, sinking river or ponornica in South Slavic languages. * Polje (karst polje, karst field), a large flat specifically karstic plain. The name "polje" derives from South Slavic languages. * Ponor, same as estavelle, sink or sinkhole in South Slavic languages, where surface flow enters an underground system * Scowle, porous irregular karstic landscape in a region of England. * Turlough (lake), Turlough (turlach), a type of disappearing lake characteristic of Ireland, Irish karst. * Uvala (landform), Uvala, a collection of multiple smaller individual sinkholes that coalesce into a compound sinkhole. The term derives from South Slavic languages (many karst-related terms derive from
South Slavic languages The South Slavic languages are one of three branches of the Slavic languages. There are approximately 30 million speakers, mainly in the Balkans. These are separated geographically from speakers of the other two Slavic branches (West Slavic lang ...
, entering scientific vocabulary through early research in the Western Balkan Dinaric Alpine karst).


See also

* * * * * * *


References


Further reading

*Ford, D.C., Williams, P., ''Karst Hydrogeology and Geomorphology'', John Wiley and Sons Ltd., 2007, *Jennings, J.N., ''Karst Geomorphology'', 2nd ed., Blackwell, 1985, *Palmer, A.N., ''Cave Geology'', 2nd Printing, Cave Books, 2009, *Marjorie Sweeting, Sweeting, M.M., ''Karst Landforms'', Macmillan, 1973, *van Beynen, P. (Ed.), ''Karst management'', Springer, 2011, *Vermeulen, J.J., Whitten, T., "Biodiversity and Cultural Property in the Management of Limestone Resources in East Asia: Lessons from East Asia", The World Bank, 1999,


External links


Speleogenesis Network, a communication platform for physical speleology and karst science research

Speleogenesis and Karst Aquifers
– a large glossary of Karst related terms
Acta Carsologica
– research papers and reviews in all the fields related to karst
CDK Citizens of the Karst
– Citizens of the Karst, a non profit NGO dedicated to the protection of the Puerto Rican Karst (English site available)


Karst Information Portal
- an open-access digital library linking scientists, managers, and explorers {{DEFAULTSORT:Karst Topography Karst, Landforms Limestone formations Geomorphology Dinaric karst formations Dinaric Alps German words and phrases