Fluvial Processes and Landforms

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Fluvial Processes and Landforms
Landforms shaped by running water are described
as fluvial landforms. The work of streams
consists of three closely related activities -
erosion, transportation, and deposition, creating
two major types of fluvial landforms erosional
landforms and depositional landforms.
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Fluvial Processes and Landforms
Erosional and depositional landforms.
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The Evolution of a Stream
The work of streams consists of three closely
related activities - erosion, transportation, and
deposition.
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The Evolution of a Stream
(a) Stream established on a land surface
dominated by landforms of recent tectonic
activity. (b) Gradation in progress. (c)
Gradation profile attained. (d) Floodplain
widened to accommodate meanders.
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Meanders
In meandering streams, erosion and deposition
occur at the banks. Point bars form where
slow-moving water deposits fine material. Cut
banks occur where faster-moving water erodes away
bank materials. See animation on meandering
streams in the geodiscoveries section of your
texts website.
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Waterfalls
Small, high waterfalls are common features of
alpine mountains carved by glacial erosion.
However, large waterfalls on major rivers are
comparatively rare. See movie on waterfalls in
the geodiscoveries section of your texts website.
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Waterfalls
A bird's-eye view of the Niagara River with its
falls and gorge carved in strata of the Niagara
Escarpment. The view is toward the southwest from
a point over Lake Ontario.
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Alluvial Fans
One very common landform built by braided,
aggrading streams is the alluvial fan, a low cone
of alluvial sands and gravels. The apex, or
central point of the fan, lies at the mouth of a
canyon or ravine. The fan is built out on an
adjacent plain.
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Alluvial Fans
A cross section shows mudflow layers interbedded
with sand layers, providing water for a well in
the fan.
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Alluvial Fans
Alluvial fan along coastal shoreline.
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