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A valley shaped like a v in cross section, these
valleys have steep sloping sides and narrow
bottoms. The river in the upper course is small
and runs fasts cutting into the landscape and
deepening the valley sides. The river at this stage
has very little energy to erode sideways, however
it does erode downwards which is how the v of
the valley forms.
The v-shaped valley is found in the upper course,
V-shaped Valley because at this stage the river has very little
energy to erode other than vertically (which is
dominant) to get down to river level. Weathering
and erosion on the valley sides removes material
and causes the valley sides to retreat and form a
v shape.…read more

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An interlocking spur is a natural geographical feature where vertical erosion is the
dominant force in determining the river's course. As the river wanders between
banks that are far apart, the high ridges of land (promontories) jut out into the river
valley in a staggered formation, interlocked together in a formation like the teeth of a
zip. These high ridges of land are referred to as interlocking spurs. The interlocking
spurs are made of more resistant rock that that around them forcing the river to go
around them.
The interlocking spurs are found in the upper course, because the river doesn't have
a huge amount of energy to erode as it does not have a high discharge and it has to
transport large pieces of sediment. So when it meets resistant rock the river winds
around it.
Spurs…read more

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Typically, a river flows over a large step in the rocks that may have been
formed by a fault line. As it increases its velocity at the edge of the waterfall,
it plucks material from the riverbed. This causes the waterfall to carve deeper
into the bed and to recede upstream. Often over time, the waterfall will
recede back to form a canyon or gorge downstream as it recedes upstream, and
it will carve deeper into the ridge above it.
Often, the rock just below the more resistant shelf will be of a softer type, meaning that
undercutting due to splash back will occur here to form a shallow cave-like formation
known as a rock shelter or plunge pool under and behind the waterfall. Eventually, the
outcropping, more resistant cap rock will collapse under pressure to add blocks of rock to
the base of the waterfall. These blocks of rock are then broken down into smaller
boulders by attrition as they collide with each other, and they also erode the base of the
waterfall by abrasion, creating a deep plunge pool or gorge.
Streams become wider and shallower just above waterfalls due to flowing over
the rock shelf, and there is usually a deep pool just below the waterfall because
of the water hitting the bottom. Waterfalls normally form in a rocky area due to
erosion. After a long period of being fully formed, the water falling off the ledge
will retreat. Eventually, as the pit at the bottom grows deeper, the waterfall
collapses under the weight of itself.…read more

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This is Niagara falls one of the largest waterfalls
in the world and is situated at the Canadian ­
American border.
·Block: Water descends from a relatively wide stream or river.
·Cascade: Water descends a series of rock steps.
·Cataract: A large, powerful waterfall.
·Fan: Water spreads horizontally as it descends while remaining in contact with bedrock.
·Horsetail: Descending water maintains some contact with bedrock.
·Plunge: Water descends vertically, losing contact with the bedrock surface.
·Punchbowl: Water descends in a constricted form and then spreads out in a wider pool.
·Segmented: Distinctly separate flows of water form as it descends.
·Tiered: Water drops in a series of distinct steps or falls.
·Multi-step: A series of waterfalls one after another of roughly the same size each with
its own sunken plunge pool.
A frozen waterfall in New York
in winter.…read more

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This is a diagram of how a waterfall is formed.…read more

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