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L55 Grand Canyon & Colorado Plateau. Grand Canyon National Park.
Arizona, USA
Position:
N36° 04'
W112° 07'
Elevation:
7000' / 2150m (Canyon rim)
Image format:
MF 35mm
GRAND CANYON & COLORADO PLATEAU. GRAND CANYON N. PARK. ARIZONA,
USA
Scenes like this of Arizona's Grand Canyon of the Colorado River
have inspired generations of young and old alike to wonder at
the beauty of the Earth's Surface. Here are some highlights to
help you appreciate the scene:
The Canyon has been carved into the surface of a plateau that
is clearly visible in the upper background of the image. The plateau
lies about 7000' (about 2100m) above sea level. The river at this
point lies is about 2000' or 600m above sea level. The Canyon
almost 1 mile (1.6 km) deep. The air temperature at the top may
be 70°F (21°C) while at the bottom it will be almost 90°F (30°C).
In winter there is often snow on the rim of the Canyon while it
is very warm at river level. So, the Canyon generates its very
own climate.
There is an INNER CANYON - visible on the right hand side of the
image. This is narrow, steep sided and has been ERODED by the
Colorado River through ancient METAMORPHIC SCHISTS and GRANITE
GNEISS rocks.
The upper or outer Canyon is wider (and getting wider as WEATHERING
and EROSION continue) and reveals layer after layer of younger,
softer SEDIMENTARY ROCKS - LIMESTONES, SANDSTONES, SHALES and
LIMESTONES. One such layer is the Red Limestone layer, which can
be traced right around the Canyon; it can be seen clearly in the
foreground of the image running upwards from the bottom left hand
corner.
Less detail
Image Trail:
L4 River canyon cut through horizontal strata. Cataract Canyon,
Colorado River
L5 Confluence of two major rivers. Colorado & Green Rivers
L8 Mountain stream on glaciated bed rock. Kerry, Ireland
L22 Waterfall. Yellowstone National Park. Wyoming, USA
L27 Massive boulders in river. Yosemite National Park. California,
USA
L28 Granite dome and waterfall. Yosemite National Park. California,
USA
L37 Incised meanders. Goosenecks, San Juan River. Utah, USA
L88 Limestone and underground river, Yorkshire, UK
H1 River in an arid area. Fremont River, Capitol Reef National Park.
Utah, USA
H2 The Glen Canyon Dam, Lake Powell, Arizona, USA
H6 River in a wet area. Kerry, Ireland
L75 Lake Powell, Utah, USA
H16 Pulp mill on major river St. John. New Brunswick, Canada
H36 Mountain Stream. Mt Rainier. Washington, USA
Links:
www.kaibab.org/geology/gc_geol.htm
http://geography.com.sg/rivers/index.html
http://geography.com.sg/weathering/index.html |
