Erosional landform
Lapies
The highly rough surface of limestone lithology characterized by low ridge and pinnacles, narrow clefts and numerous solution holes is called lapies. lapies are variously named in different part of the world that are; Clint in North England, Karren in Germany, bogar in Earstwhile Yugoslavia etc. lapies are generally formed due to corrosion of limestone along their joints when limestone are well exposed at the ground surface
Sinkholes
Chemically active rainwater charged with atmosphere carbon dioxide dissolved limestone and other carbonate Rock along their joints and thus various type of solution hole developed at the ground surface when limestone are directly exposed to the atmospheric process.
Smaller holes are called sinkholes while are generally of two types that are
- Funnel shaped sinkhole
- Cylindrical sinkhole
Some Shallow holes are further enlarge due to continuous solution into large depression which are called Dolines in the karst region and doline in Serbia. a feature almost similar to doline in appearance but with Shallow depth and large area extent is called solution pan. When the water cannot percolate downward and the doline is filled with water Sach doline full of water are called karst lakes.
Uvalas
Extensive depression are called uvalas which are up to one km across. They are formed in a number of ways e. g
- Due to coalescence(fuse) of several doline due to containers solution and enlargement of doline.
- Due To collapse of upper roof of a large cavities form underground.
- Due to coalescence of various sinkhole.
Poijes
Most extensive large then do line depression are called poljes. it is a closed basin of elliptical shape they are found in karst region of Earstwhile Yugoslavia and in Jamaica.They are formed due to downfolding and downfaulting of limestone area due to Earth movement. The resultant grabens are then modified by solution work of water.
Caves
Cave are void of the large dimension below the ground surface in fact they were the most significant landforms produced by erosional work of groundwater in limestone lithology. Carlsbad cave of USA are the example of very expensive cave. Limestone cave are found in India near Dehradun in Uttar Pradesh (Sahastradhara ,Robert cave) ,in Bihar Gupta Dham cave Bastar district of Chhattisgarh Kutumbsar cave and in Madhya Pradesh Gupt Godavari cave.
Formation of cave
Caves are formed due to collision (aberasion) of limestone why groundwater in the vadose zone above the water table of groundwater.
some scientist believe that cave are formed by phreatic (zone of saturation,) water under hydrostatic pressure below water table.
some geomorphologist suggested that caves are not formed by fratta quarter water under hydrostatic pressure but are formed by the lateral flow of watervadose zone.
Features of Caves
- Ponores
- Natural Bridge
Depositional landform
All type of deposits in the cave are collectively called speleothems. The landform are
- Stalagmite
- Cave pillars ( formed when stalactite and stalagmite meet together )
- Helictite and Heligmite ( dripstone growing side word from stalactite and stalagmite )
For Short Notes plz visit on https://nikitanirmalgeoinformation.blogspot.com/2018/10/summary-on-karst-topography.html
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