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L36 Weathering, erosion and deposition. Capitol Reef National Park,
Utah, USA
Position:
N38° 17'
W111° 16' approx.
Elevation:
6200'/ 1890m approx.
Image format:
MF 35mm
THE CHANGING LANDSCAPE
The earth's surface is changing. The changes may be very, very
slow or quite fast..
You can get some idea of what's going on in this photograph. Rocks
on the cliff faces on being heated by day and cooled by night,
wetted during rain and dried by the sun, frozen by frosts and
then thawed out. And there is a whole range of chemical processes,
at work. The combined effect is to break large rocks down in to
smaller pieces and to change the mineral in the rocks. The rocks
and their minerals breakdown and decay. This process is called
WEATHERING.
Meanwhile, rain and wind remove loose fragments from the cliff
faces and these accumulate on the lower levels where they are
moved further down-hill, mainly, by running water.
In this image, all the material that has built up at the bottom
of the cliffs is being eroded by small streams. These all flow
into each other to form a stream system which, though dry for
most of the time, do a lot of damage. A dry stream bed or WADI
as it is called can be seen in the foreground of the image.
More detail
Image Trail:
L4 River canyon cut through horizontal strata. Cataract Canyon,
Colorado River
L25 Gullied Butte - badlands. Grand Mesa, Grand Junction. Colorado,
USA
L30 Debris flow. Henry Mountains. Utah, USA
L32 Eroded escarpment. Utah, USA
L33 Eroded escarpment. Utah, USA
L34 Gullied Butte - badlands. Factory Butte, Hanksville. Utah, USA
L42 Badlands. Bryce Canyon National Park. Utah, USA
L43 Badlands. Bryce Canyon National Park. Utah, USA
Links:
many photographs of the rocks in this area at http://donb.photo.net/photo_cd/h/
http://geography.com.sg/weathering/index.html
http://geography.com.sg/rivers/index.html
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