This document discusses different types of erosional and depositional landforms created by river processes. It describes landforms such as V-shaped valleys and waterfalls that are created by erosion, and floodplains and deltas that are formed by deposition. It also explains the factors that influence fluvial erosion and the formation of various erosional features like interlocking spurs, rapids, and potholes.

2. Erosional landforms
Depositional landforms
Types of channel
The long profile

3. Two major groups of landforms:
Erosional landforms
Depositional landforms

4. EROSIONAL DEPOSITIONAL COMBINED EFFECTS
LANDFORMS LANDFORMS OF EROSION &
DEPOSITION
- V-shaped valley Floodplains Pools & riffles
- Interlocking spurs Levees Meanders & Ox-bow
lakes
- Waterfalls Braiding River terraces
- Rapids Delta
- Gorges Alluvial fan
- Potholes

5.  Upper zone: large, angular
boulders often block river
channels
Produces a large wetted
perimeter  high friction
which uses up much river’s
energy
 After friction overcome 
little energy is available for
eroding and transporting
material

6.  Steep slope  small amt of water can move large
boulder with the help of gravity
 After heavy rain or snowmelt  material transported
 Water flowing between boulders become turbulent
dislodging particles increasing transportation
 Large amt of large particles  mean high rates of
abrasion / corassion cutting into channel bed
 A river erode vertically by traction or saltation which
resulted in a steep-sided valley called a V-shaped
valley.

12. (i) Climate:
Rainfall  lubricates and increases the weight of hillsides
 increases discharge which erodes river bed and
removes bedload.
(ii) Rock structure:
- hard rocks are erosion resistant and produce steep valley
- soft rocks give gentler valley
(iii) Vegetation:
it helps to bind soil together and keep the hill slope more
stable.
Interception reduce the amt of rainfall that reaches the soil
surface.

13. Interlocking spur.
It forms because
the river is forced
to follow a
winding course
around the
protrusions of
the surrounding
highland,
resulting in spurs
interlock.

17.  Is a sudden
step in a river’s
long profile
 Causes the
rejuvenation of
a river

18.  Tallest waterfalls in
the world
 Height: 979 m
(3,212 ft)

19.  Forms when water flows over sudden change in gradient
 The fall is so fast that the water, by hydraulic action
erodes rock at the base
 The loose material is used as tool to further erode and
deepen the base by abrasion to form a plunge pool
 The undercutting at the base of the waterfall creates a
overhanging cliff, which will eventually collapse.
 A waterfall may appear to retreat upstream (headward
erosion), leaving a deep sided gorge.

20.  a band of resistant rock lies over a layer of
less resistant rock – Niagara Falls on the
USA- Canada border
 When a fault-line scrap lies across a river –
Victoria Falls in Zambia-Zimbabwe, Africa
 When a river plunges down the edge of a
plateau – Livingstone Falls in Zaire, Africa

26.  Are associated with very disturbed turbulent water
 Usually occur in the upper coarse of the river where
the long profile of the river is steep
 Sometimes river on the area with alternating bonds
of resistant and less resistant rock
 Less resistant rock erodes much faster than the
resistant rock by the process of hydraulic action
which they create an uneven river bed

28. Rapids are mini-
waterfalls
Shallow, slow flowing
river due to large
amount of friction.
Protruding bands of
more resistant strata
create steps over
which rapids fall - the
river bed is ungraded

30. A deep
narrow
valley with
almost
vertical
wall.

32.  What?
 Cylindrical
holes drilled into
the rock by
turbulent high
velocity flow.

33. How?
 Potholes in the beds of rivers are common
feature of rapid abrasion
 Vertical eddies may be strong enough to
rotate a small pebble, which grinds a hole in
the rock.
 Overtime, they may widen and join with other
potholes to form larger potholes and the
whole river is deepened.
 It is most active when river levels are high