K

Karst

Karst is an unusual word used to describe an interesting set of landforms and land-

forming processes. The word is the Germanic version of the SlovenianKras,

which refers to a particular limestone plateau in Slovenia and Italy that was named

for being barren. It was there that the classic scientific descriptions of theland-

scapewere made and, so, the Kras landforms were used as archetypes for features

in many other places in the world. Several other languages, including Latin and

Chinese, have their own terminologies, but the scientific community useskarst

and other words to describe the landforms of the Kras Plateau or to any similarly

formed surfaces.

Karstic landscapes are widely spread and found in areas underlain by particular

rock types, structures, and goodly amounts of precipitation under tropical and

middle latitudetemperatureconditions. Additionally, some of today’s areas are

the products of paleoclimates no longer in existence at those locations. Prominent

areas of karst are found in Morocco, the United Kingdom, France, Australia,

China, Slovenia, Italy, the United States (the Ozarks, Appalachians, and Florida),

Russia (Urals and eastern Siberia), Brazil, Mexico, Costa Rica, South Africa,

Namibia, Thailand, Vietnam, and Papua New Guinea. It must be recognized,

though, that karst regions represent a minority of the surface areas of these places.

Karst landscapes can be quite rugged or very gentle depending on the subsurface

rock, amount of precipitation, and thelength of time over which the landscape

has evolved.

Most landscapes result from the erosion and deposition caused by a complicated

interplay of factors energized by climate. The absolutely distinctive identifying

feature of karst landscapes is that they are places where underground solution of

bedrock has been dominant in shaping the surface. Water is sometimes called the

“universal solvent” because it is able to dissolve all natural materials given enough

time. Whereas we think of rock as being permanent, it is hardly so in the context of

Earthhistory. The solution rates of various rocks vary by millions of times and it is

some of the fastest rates that are associated with karst.

Water is much more effective in dissolving rock when the water contains impu-

rities. Water infiltrating the rock incorporates atmospheric carbon dioxide and it is

this weak carbonic acid that is a potent dissolver of some types of rocks. Also,

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