Download Landscape Evolution: Geomorphology Relief Relief

Chapter 16
Topography is a Balance Between
Erosion and Tectonic Uplift
Landscape Evolution:
Geomorphology
Topography is a Balance Between
Erosion and Tectonic Uplift
Relief
Relief
• The relief in an area is the
maximum difference between
the highest and lowest
elevation.
– We have about 7000 feet of relief
between Boulder and the
Continental divide.
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Mountains and Valleys
• A mountain is a large mass of rock that
projects above surrounding terrain.
• A mountain range is a continuous area of
high elevation and high relief.
• A valley is an area of low relief typically
formed by and drained by a single stream.
• A basin is a large low-lying area of low
relief. In arid areas basins commonly have
closed topography (no river outlet to the
sea).
Mountain Landforms:
Horn
Valleys and Basins
• River Valleys
– U-shape (Glacial)
– V-shape (Active Water erosion)
– Flat-floored (depositional flood plain)
Mountains
• Typically occur in ranges.
• Glaciated forms
– Horn
– Arête
• Desert Mountains
– Vertical Cliffs
– Alluvial Fans
Deserts: Vertical Cliffs and
Alluvial Fans
U-shaped Valley:
Glacial Erosion
• Tectonic (Fault) Valleys (Basins)
–
–
–
–
Tectonic origin
San Luis Valley
Jackson Hole
Great Basin
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V-shaped Valley:
Active water erosion
Desert and Semi-arid
Landforms
• A plateau is a broad area of uplift
with relatively little internal relief.
Flat-floored Valley:
Depositional Flood Plain
Plateau, Mesa, Butte
• A mesa is a small (<10
km2)plateau bounded by cliffs,
commonly in an area of flat-lying
sedimentary rocks.
• A butte is a small (<1000m 2) hill
bounded by cliffs
Colorado National Monument
Canyonlands
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Cuesta
Desert and Semi-arid
Landforms
• A cuesta is an asymmetric ridge in
dipping sedimentary rocks as the
Flatirons.
• A hogback is ridge formed by nearvertical, resistant sedimentary rock.
(Dakota Ridge)
• Badlands are areas of deeply gullied
topography unsuitable for agriculture.
Hogback
Badlands
Landform Terms
• Relief
• Mountain
• Mountain
Range
• Valley
• Basin
• Horn
• Arête
• Alluvial Fan
• U-shaped
Valley
• V-shaped
Valley
• Plateau
• Mesa
• Butte
• Cuesta
• Hogback
• Badlands
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