Karst topography is formed by the dissolution of soluble rocks like limestone by surface water and groundwater. Key conditions for karst topography include thick soluble rock near the surface, fractures in the rock, and moderate rainfall. Rainwater picks up carbon dioxide to form weak carbonic acid, which dissolves cracks in the limestone over time, enlarging fractures and creating underground drainage systems. Common surface features of karst terrain include sinkholes, springs, dry valleys, and disappearing streams. Subsurface features include caves, underground streams, stalactites that grow downward from cave ceilings, and stalagmites that form on cave floors.

1. KRAST TOPOGRAPHY

2. Introduction
• In simple words, the term karst describes a
distinctive topography that indicates
dissolution of underlying soluble rocks by
surface water or ground water.
• Although commonly associated with
carbonate rocks (limestone and dolomite)
other highly soluble rocks such as evaporates
(gypsum and rock salt) can be sculpted into
karst terrain.

3. Essential conditions
• Relatively thick massive soluble rock, i.e.,
limestone, dolomite, or chalk.
• Carbonate rocks should be very close to the
ground surface.
• Limestone should be highly folded, faulted or
fractured.
• Considerable relief so that water is capable of
circulation to cause typical karst topography.
• Moderate to heavy rainfall to cause solution
of rocks.

4. Development of Karst terrain
• As rain falls through the atmosphere it picks
up carbon dioxide (CO2).
• When this rain reaches the ground and
passes through the soil it picks up more CO2
and forms a weak solution of carbonic acid.
• As the acidified rain water trickles down
through cracks in the limestone, it begins to
dissolve the rock.
• Over time it progressively enlarges the cracks
and openings in the ground an underground
drainage system starts to develop.

6. SURFACE FEATURES
• Examples of some of the most common
surface karst features encountered are as
follows:
Sinkhole
A topographically closed
depression that is circular
or elliptical in shape and
with steep to vertical
sidewalls.

7. • Karst springs
• These are the natural
outflows of karst
groundwater onto the
surface. They form
where the water table
reaches the surface.
SURFACE FEATURES

8. SURFACE FEATURES
• Karst valley:
• Larger karst landforms
include dry valleys and
gorges, carved by past
rivers that now flow
underground

9. SURFACE FEATURES
• Solution valley:
• The collapse of a
cavern over a large
area can create a
feature referred to as
a solution valley or
basin, sometimes
referred to as a karst
gulf

10. SURFACE FEATURES
• Disappearing Stream:
• A stream that disappears
into an underground
channel and does not
reappear in the same, or
even in an adjacent,
drainage basin.
• In karst regions, streams
commonly disappear into
sinkholes and follow
channels through caves.

12. SUBSURFACE FEATURES
• Cave
• Karst Caves are voids in the
rock that form naturally
when water erodes away
limestone or other soluble
rocks.
• Karst caves are shaped by
chemical weathering of the
bedrock. These formations
are commonly found in
limestone areas.

13. SUBSURFACE FEATURES
• Underground Stream:
• A body of subsurface
water flowing through a
cave or a group of
communicating caves,
as in a karst region

15. SUBSURFACE FEATURES
• Stalactites:
• Stalactites are mineral
depositions that
originate from the ceiling
of a cave and continue to
“grow” downward
towards the ground.
• They are rock formations
that have a duct in the
center, through which
water continues to
circulate with minerals.

17. SUBSURFACE FEATURES
• Stalagmites:
• Stalagmites are mineral
depositions originated in
the floor of a cave and,
unlike stalactites; they do
not have the central duct
such as stalactites
• They are usually solid
shapes much more
rounded and irregular than
stalactites.

19. ___________The End