karst and karst terranes word is german form of the yugoslavian term “kras” means “bare stony...
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Karst and Karst TerranesWord is German form of the Yugoslavian term “Kras” means “bare stony ground”
Named after investigating a region near the Adriatic Sea in Yugoslavia
In modern Geomorphology the term refers to any landscape formed by dissolution of the underlying bedrock
Characterized by distinctive landforms which don’t typically
occur in any other circumstance
Pseudokarst is the term for karst-like development in non-carbonate lithology that exhibits characteristics similar to karst landscapes, but which lack dissolution as a primary means of landscape formation.
Karst and Karst TerranesWord is German form of the Yugoslavian term “Kras” means “bare stony ground”
Named after investigating a region near the Adriatic Sea in Yugoslavia
In modern Geomorphology the term refers to any landscape formed by dissolution of the underlying bedrock
Characterized by distinctive landforms which don’t typically
occur in any other circumstance
Pseudokarst is the term for karst-like development in non-carbonate lithology that exhibits characteristics similar to karst landscapes, but which lack dissolution as a primary means of landscape formation.
Major known Karst regions of the worldMajor known Karst regions of the world
Factors affecting KarstSolubility of Limestone
- percent calcite
Climate
- Temperature and Moisture
Structure of Limestone
- joints, fractures, porosity,
Mineralogy/lithological content
% clastics, % spar vs micrite vs skeletal
Vegetation/Non-carbonate Geology
- acidity (pH) of groundwater
Atmospheric CO2
- affects solubility of Carbonates
Factors affecting KarstSolubility of Limestone
- percent calcite
Climate
- Temperature and Moisture
Structure of Limestone
- joints, fractures, porosity,
Mineralogy/lithological content
% clastics, % spar vs micrite vs skeletal
Vegetation/Non-carbonate Geology
- acidity (pH) of groundwater
Atmospheric CO2
- affects solubility of Carbonates
Dissolution of Carbonates
CaCO3 dissociates into its constituent ionic components in water
CaCO3 Ca2+ + CO32-
(Limestone)
CaMg(CO3)2 Ca2+ + Mg2+ + 2CO32-
(Dolomite)
However, dissolution occurs more frequently as a result of a reaction with carbonic acid formed with carbon dioxide
CaCO3 + H2O + 2CO2 Ca2+ + 2HCO3-
CaMg(CO3)2 + 2H20 + 2CO2 Ca2+ + Mg2+ + 4HCO3
-
Karst Collapse LandformsSinkhole - a.k.a. Doline comes in a variety of shapes most often funnel shaped forms as material above a cavity becomes too thin to support the weight sometimes filled with colluvium from edges of feature
can form circular lakes often entrances to caves are found in sinkholes
related to formation of featureCompound sinks - a.k.a. Uvalas several sinkholes coalesce to form a larger structure these may be quite large (a kilometer)
Occasionally, uvalas are floored with alluvium derived from subterranean streams called a
karst gulf or a polje
Karst Collapse LandformsSinkhole - a.k.a. Doline comes in a variety of shapes most often funnel shaped forms as material above a cavity becomes too thin to support the weight sometimes filled with colluvium from edges of feature
can form circular lakes often entrances to caves are found in sinkholes
related to formation of featureCompound sinks - a.k.a. Uvalas several sinkholes coalesce to form a larger structure these may be quite large (a kilometer)
Occasionally, uvalas are floored with alluvium derived from subterranean streams called a
karst gulf or a polje
A Sinkhole (cockpit) in Central America
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Karst features in Florida
Karst features in Florida
Karst terrane in Australia - a karren plain with blind valleys and numerous sinkholes
Karst terrane in Australia - a karren plain with blind valleys and numerous sinkholes
A doline (sinkhole)in Winterpark, FL
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A 300 ft deep sinkhole in Guatemala
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“The Blue Hole” is an underwater sinkhole, 1000 ft across & 400 ft deep
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Karst Landforms- stream featureschaotic or deranged drainage patterns
few, if any, through flowing streams in karst regions
often exhibit what are called blind valleys
e.g., Lost river, tributaries and other surface streams in the Mitchell plain
streams disappear into a swallow hole called a ponor, a swallet, or a sink
-Tolliver Swallow; Stein Swallow
often reappear as a karst spring or a groundwater rise
-Orangeville rise;
-Wesley Chapel Gulf rise
Karst Landforms- stream featureschaotic or deranged drainage patterns
few, if any, through flowing streams in karst regions
often exhibit what are called blind valleys
e.g., Lost river, tributaries and other surface streams in the Mitchell plain
streams disappear into a swallow hole called a ponor, a swallet, or a sink
-Tolliver Swallow; Stein Swallow
often reappear as a karst spring or a groundwater rise
-Orangeville rise;
-Wesley Chapel Gulf rise
Drainage in a Karst region in Europe
-flooded and backed up into the overflow channels
- polje
Drainage in a Karst region in Europe
-flooded and backed up into the overflow channels
- polje
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A rise of a subterranean streamA rise of a subterranean stream
Solution pan on a karren in the southwestern USA
Solution pan on a karren in the southwestern USA
Karst landforms- denudation often large tracts of limestone karst terranes are devoid of unconsolidated material these areas are called Karrens
Often have solution enhanced vertical fracture and joints sets
they can be filled with debris from dissolution or devoid of residuum
known as grikes, kluftkarren or solution grooves
Karst landforms- denudation often large tracts of limestone karst terranes are devoid of unconsolidated material these areas are called Karrens
Often have solution enhanced vertical fracture and joints sets
they can be filled with debris from dissolution or devoid of residuum
known as grikes, kluftkarren or solution grooves
Grikes or Kluftkarren - a.k.a. solution enhanced vertical fractures.
the grikes divide the surface into distinct pieces referred to as Clints
Grikes or Kluftkarren - a.k.a. solution enhanced vertical fractures.
the grikes divide the surface into distinct pieces referred to as Clints
Closeup of a Karren with grikes
Soils developed in karst terranes commonly develop a thick red cap called terra rosa
origins are debated and may be site specific composed of clay rich in iron sesquioxide mineralsCommonly thought of as leftovers after intense leaching of surface rock May also have contribution by loess and other windtransported sediments
Less commonly develop another type of soil that is thin, very permeable and porous called rendzinasallow extreme infiltration
loamy with pieces of limestone residuum
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terra rosa soilterra rosa soil
loessloess
Karren with Grikes in Ireland
Karren with Grikes in Ireland
Grikes or cutters, filled with terra rosa, shown in cross-section in a roadcut
Grikes or cutters, filled with terra rosa, shown in cross-section in a roadcut
Karst terranes in high humidity regions
forms a variety of spectacular landforms
Towers, Mounds and Cockpits
-erosional remnants of thick sequences of
limestone that have been greatly degraded
Karst terranes in high humidity regions
forms a variety of spectacular landforms
Towers, Mounds and Cockpits
-erosional remnants of thick sequences of
limestone that have been greatly degraded
Cockpit karst region in JamaicaCockpit karst region in Jamaica
Tower karst in S.E. China
Tower karst in S.E. China
Tower Karst in S.E. ChinaTower Karst in S.E. China
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Eastern Illinois basin strata and karst development
Mitchell Plain and Chester Escarpment
Sinking stream in karst area of Kentucky
Sinkhole plain in the Kentucky equivalent of the Mitchell PlainSinkhole plain in the Kentucky equivalent of the Mitchell Plain