Transcript The Geology of the Grand Canyon

The Geology of the Grand Canyon
Hannah Avery and Sarah Lowe
General Info about the Canyon
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Located in Northwestern Arizona
Covers 1,218,375 acres of land
Deepest point 6,000 feet
Widest point 15 miles
How the Canyon Formed
• No one knows for sure but…
– It is believed that…
• It is a combination of many things
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Erosion (By water and ice)
Wind
Colorado River course
Volcanism
Continental Drift
Variations in Earth’s Orbit
Erosion by Water
• Located in desert so soil is less absorbent
causing flash floods
• Flash floods can move automobiles, buses,
and small houses
– “If automobiles, buses, and small houses are in
the way then it will take them too.”
Erosion by Ice
• Water seeps into cracks and freezes, the
freezing water expands, expanding the
cracks.
• Expansion causes rocks to be pushed into
the canyon causing Rock Falls
• Rock Falls often take out hiking trails
Layers of the Grand Canyon
Other Facts
• Roots of the ancient mountain range that
lies at the base of the canyon was formed
approximately 1.7 billion years ago
• Climate is considered semi-arid
• Colors are due to different amounts of
minerals in the rocks
References
• http://www2.nature.nps.gov/geology/parks/
grca/index.cfm
• http://www.kaibab.org/geology/gc_geol.htm
#when
• http://en.wikipedia.org/wiki/Geology_of_the
_Grand_Canyon_area
• http://www.pbs.org/wgbh/amex/canyon/sfea
ture/geology.html