The document discusses various geomorphological landforms associated with fluvial cycles in humid and arid regions, detailing features such as straths, knick-points, bad-lands, and escarpments. It explains landforms formed through erosion and deposition, including mesas, buttes, and natural levees, as well as drainage patterns like dendritic and parallel configurations. The text also touches on the classification of river patterns based on their evolution and relationship to the topographic features.

1. Geomorphological
Landforms
(Part - I)
By Uddipta Mohanta

2. Features and typical landforms associated with an
ideal fluvial cycle in a humid region

3. STRATH
When the width of the valley is greater than th width of the river, the valley is called
a Strath.

4. KNICK-POINT
During the process of regression there is a more or less marked change in the
slope at the point of intersection of the newly graded profile with the older one. It is
known as Knick-point.

5. BAD-LAND
Due to extensive erosion by running water
areas get intricately traversed by gullies,
which gets mostly developed in
argillaceous rocks known as Bad-land.

6. ESCARPMENT
These are erosional landforms produced by rivers in regions of alternating beds of
hard and soft rocks. The differential erosion of rocks gives rise to a steep slope,
called escarpment.

7. CUESTAS
These erosional landforms are
developed on resistant strata
having low to moderate dip. This
has the shape of an asymmetric
low ridge or hill belt with a steep
scarp on one side and a gentle
slope on the other.

8. MESA
In regions of horizontal strata in
which isolated portion of land is
capped by a hard,
erosion-resistant bed, the
erosional landforms produced will
have an isolated table-land area
with steep sides, commonly
mesa.

9. BUTTE
With continuous erosion, the sides
of the mesa are reduced to a
smaller flat topped hill, known as
butte. In South Africa they are
called Kopjes.

10. PENEPLAIN
It is the term used for nearly
smooth erosional surface of
relatively low relief and
altitude which covers a large
area.

11. NATURAL LEVEE
On the flood plains, long depositional ridges extending parallel to the river are
found, which are known as Natural Levee.

12. Features found in Arid regions

13. ALLUVIAL FANS
Rivers reduce their velocity as
well as carrying capacity as they
descend to the plains from the
mountains. At this point the river
deposits a large amount of load
which takes a fan or Conical
shape.

14. PEDIMENT
It is a plain of eroded bedrock in
an arid region developed
between mountain and basin
areas. Pediments converge to
from Pediplains.

15. BORNHARDTS
If pediments exists on both sides
of a mountain range, they
gradually converge. Eventually the
range is reduced to a very broad
dome with the slope equal to that
of the pediments on either side of
the crest that consists of a narrow
ridge of small scattered domes.
These residual hills are known as
Bornhardts.

16. PLAYAS
In deserts consisting of basins
enclosed by mountain ranges
the drainage is towards the
centre of the basin from all
margins. When there is
sufficient water, this plain is
covered by a broad shallow
lake called Playa.

17. WADIES
They are channels formed
during rains in desert or arid
regions.

18. INSELBERGS
These are isolated mounds rising
above general level of pediment.

19. SLOUGHS (Depositional feature)
Depressions on the flood plains of meandering rivers, which are excavated during
floods due to the tendency of the overflowing water to follow short course.

20. River Patterns

21. River Patterns
Antecedant: Rivers exiting before the surface relief was imposed upon the area.
Consequent: The flow of the river occurs as a result of the existing surface relief.
Subsequent: The river which joins the consequent river arising later as erosion proceeds.
Insequent: It displays no reason for its particular course.
Obsequent: The river drains in opposite direction to the original consequent river.
Resequent: The river drains in the same direction as the original consequent river, but at a lower topographic level.
Superimposed: At some places older rocks may be covered by sheet of new deposits. Any river developed on such
area will follow the surface relief of the overlying cover and will not have any relation to the older rocks below.
Gradual erosion removes the overlying cover and the river is said to be superimposed on the older rocks below.

22. River Patterns

23. Drainage Patterns

24. Drainage Patterns
Dendritic: It is characterised by irregular branching of tributary streams in a similar
pattern as that of a tree’s branch.
Parallel Pattern: It develops on steep slopes where the tributaries and the master
stream flow parallel to each other.
Trellis pattern: It develop in a topography created on a folded structure of syncline
and anticline, faults or joints.
Radial Pattern: It consists of drainage lines radiating from a central part as on a
dome.

25. Drainage Patterns