KARST landscapes consist of limestone areas that have been sculpted by a combination of erosion and chemical dissolution to form dramatic topographies such as that typified by the Cockpit Country.
Much of the pioneering work in karst began in
Yugoslavia. In fact, the term "karst" comes from the Slav word,
"krs," and is associated with the limestone country in western
Slovenia. Other terminology, such as
doline, uvala, and polje, also originated here (Jennings,
1971).
On Jamaica, the karstification of the White and Yellow Limestone
Groups, which vary considerably in quality (e.g., purity, hardness)
and depth, has resulted in a landscape varying from gently rolling,
soil-covered plains through rough and jumbled deep depressions,
isolated towers, and pointed hills. (White 1988). Cockpit
karst is a special form of "Conekarst" in which the residual
hills are chiefly hemispheroidal and surround closed, lobed,
depressions known as dolines or "cockpits" each of which is drained
to the aquifer by one or more sinkholes. The dolines have concave
floors covered with a variable amount of rock rubble and soil,
which, in Jamaica, has often been redistributed to form a flat
floor as a result of repeated floodings. The hilltops and slopes
are marked by a distinctively minimal clay soil and organic humus
while the talus have retained soil coverage.
Cockpits average in depth
from 100 - 120m and walls generally slope from 30 - 40deg. Drainage
of the cockpit bottoms occurs via percolation or by sinkhole.
Drainage by the latter creates a complex, subterranean cellular
network. The periphery of Cockpit Country is marked by 'degraded'
cockpits, glades and valleys (poljes), such as seen in the Windsor, Pantrepant, and Fontabelle areas, terminating to the west in
the Queen of Spain's Valley, the best known and largest polje in
Jamaica. "Tower" karst (steep, near vertical sides) is found to the
north in the Duanvale Fault zone as well as in the southeast
region.
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