Karst Topography

1. Karst Karst Topography Topography

2. Karst Karst Topography Topography
„„
A form of landform denudation based almost A form of landform denudation based almost
exclusively on carbonation (chemical exclusively on carbonation (chemical
weathering) weathering)
„„
Chemical weathering of joints and fractures can create Chemical weathering of joints and fractures can create
huge subsurface cavities huge subsurface cavities
„„
Requirements for formation [Note connection Requirements for formation [Note connection
to hydrologic cycle] to hydrologic cycle]
„„
Water Water
„„
Limestone must be at least 80% calcium carbonate Limestone must be at least 80% calcium carbonate
(CaCO (CaCO
33
))
„„
Limestone must have a complex network of joints for Limestone must have a complex network of joints for
water to pass through water to pass through
„„
A zone of aeration (allows for water to flow) A zone of aeration (allows for water to flow)
„„
Vegetation cover providing different acids Vegetation cover providing different acids

4. „„
Features of Features of Karst Karstlandscapes landscapes
„„
Sinkholes Sinkholes
„„
Caves and Caverns Caves and Caverns
„„
Poor surface drainage Poor surface drainage
„„
Disappearing surface streams Disappearing surface streams
„„
Underground rivers Underground rivers

5. „„
Sinkholes Sinkholes
„„
Depressions in the Depressions in the
landscape landscape
„„
Formed by water Formed by water
draining through a draining through a
joint joint
„„
Doline Doline: A sinkhole : A sinkhole
that intersects the that intersects the
water table, water table,
forming a small lake forming a small lake
„„
Collapse Sinkhole: Collapse Sinkhole:
sinkhole breaks sinkhole breaks
through roof of through roof of
underlying cavern underlying cavern
Devil’s Sinkhole

14. „„
Caves and Caverns Caves and Caverns
„„
Caverns typically form near the water Caverns typically form near the water
table, such that fluctuations in the level of table, such that fluctuations in the level of
the water table alternately inundate and the water table alternately inundate and
drain them drain them
„„
Phreatic Phreaticzone zone
„„
Lowering of the water table (or uplift) later Lowering of the water table (or uplift) later
keeps them drained keeps them drained
„„
Dripstone: stalactites, stalagmites, Dripstone: stalactites, stalagmites,
columns columns

16. Column Column
Stalactite Stalactite
Stalagmite Stalagmite