The document discusses different types of erosion features including waterfalls, ox-bow lakes, V-shaped valleys, and rapids. Waterfalls are formed by erosion of resistant bedrock. Ox-bow lakes are formed when a river cuts off its own meander. V-shaped valleys are created by vertical erosion in the upper courses of rivers. Rapids occur where the river becomes shallower and rocks are exposed, increasing water turbulence.

1. Features Of Erosion
By Jesse, Abdullahi, John, Nderitu
and Angela.
1

2. Waterfalls
• Waterfalls are usually
formed when a river moves
over resistant bedrock and
erodes it slowly while
downstream it happens
faster.
• As this happens material is
plucked from a river bed
which causes the waterfall to
carve deeper into the
riverbed and recede
upstream
• part of the bedrock (hard
rock) will later break off,
exposing the soft rock, and
form a waterfall.
• The rest is in the diagram on
your right
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3. OX BOW LAKES
• An ox bow lake is a U - shaped water body or
meander that is cut of by erosion to form a lake.
• They are formed when a river has a very curve
us meander, which is nearly meeting the other
side of the river.
• Due to erosion and deposition the neck of the
meander becomes very narrow which allows
water to pass straight, flowing past the old
meander.
• Deposition then occurs, sealing of the meander.
• The deposition then totally covers up the
meander so no more water can pass.
• Over time the closed meander completely cuts of
from the rest of the river.
• The end result is a straight river separated from
a curved C-shaped lake.
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4. OX BOW LAKES
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5. V-shaped valleys.
• In the upper course of a river,
water flows at a high speed
through a narrow channel with a
steep gradient.
• As it does, so it cuts downwards.
• This vertical erosion results in a
number of distinctive landforms
including, the steep sloped v-
shaped-valleys
• Through this the river flows in it's
upper course.
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6. Formation of v-shaped-valleys.
• Vertical erosion leads to the
development of steep sided,
narrow valleys shaped like the
letter V.
• The valley sides are steep due to
the soil and loose rock being
washed downhill following periods
of heavy rainfall.
• The material is then added to the
load of the river.
• The river itself forced to wind its
way through protruding hillsides.
• These hillsides known as
interlocking spurs restrict the view
up or down the valley.
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7. RAPIDS
• A river rapid is a section of a river
with a steep gradient, which cases
an increase in the water velocity
and the turbulence.
• A rapid is caused by the river
becoming shallower and having
some materials, like rocks, to be
exposed above the flow surface.
• In rapids, water turns white
because flowing water splashes
over and around the rocks, and air
bubbles mix with them.
• This colour is normally called
“White water”.
• Rapids normally occur when the
river bed is highly resistant to
erosion.
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8. Rapids
• Rapids are categorized into several
classes:
• Class 1- This is when the river has small
waves in fast flowing water and has very
few obstacles, e.g. rocks.
• Class 2- When the river has wide
channels and rapids , without many
turns and obstacles.
• Class 3- This class has strong currents
with many obstacles in the river.
• Class 4- Powerful rapids with big waves
• Class 5-Very violent and dangerous
rapids with tight turns
• Class 6- This last stage is the most
violent and strong. This rapid can cause
death easily.
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9. Rapids
• Many people use these river
rapids to have fun.
• Rafting, is a sport which requires
rapids.
• Rafting courses are also
classified using these rapid
classes.
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