KARST

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).

GEOMORPHOLOGY 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... (White 1988). Erosion of the limestone has created a dramatic topography of rounded peaks and steep-sided, star-shaped, depressions known as .Cockpit karst.
Cockpits are distinct from dolines in being deeper and not being circular in plan. On a contour map of a doline area [e.g. Dry Harbour Mountains], circular contour lines indicate the locations of negative relief elements (depressions), whereas on a contour map of cockpit karst terrain it is the positive relief features (the conical hills) that are shown by circular contour lines. (Lyew-Ayee, P., H. A. Viles, and G.E. Tucker. 2007. The use of GIS-based digital morphometric techniques in the study of cockpit karst Earth Surface Processes and Landforms. Vol. 32, pp 165-179). 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.

We value your feedback and comments:
 HOME