2. Karst Topography
A form of landform denudation based almost
exclusively on carbonation (chemical
weathering)
Chemical weathering of joints and fractures can create
huge subsurface cavities
Requirements for formation [Note connection
to hydrologic cycle]
Water
Limestone must be at least 80% calcium carbonate
(CaCO3)
Limestone must have a complex network of joints for
water to pass through
A zone of aeration (allows for water to flow)
Vegetation cover providing different acids
3.
4. Features of Karst landscapes
Sinkholes
Caves and Caverns
Poor surface drainage
Disappearing surface streams
Underground rivers
5. Sinkholes
Depressions in the
landscape
Formed by water
draining through a
joint
Doline: A sinkhole
that intersects the
water table,
forming a small lake
Collapse Sinkhole:
sinkhole breaks
through roof of Devil’s Sinkhole
underlying cavern
6.
7.
8.
9.
10.
11.
12.
13.
14. Caves and Caverns
Caverns typically form near the water
table, such that fluctuations in the level of
the water table alternately inundate and
drain them
Phreatic zone
Lowering of the water table (or uplift) later
keeps them drained
Dripstone: stalactites, stalagmites,
columns
![Karst Topography
A form of landform denudation based almost
exclusively on carbonation (chemical
weathering)
Chemical weathering of joints and fractures can create
huge subsurface cavities
Requirements for formation [Note connection
to hydrologic cycle]
Water
Limestone must be at least 80% calcium carbonate
(CaCO3)
Limestone must have a complex network of joints for
water to pass through
A zone of aeration (allows for water to flow)
Vegetation cover providing different acids](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)