Investigation 3: Go with the Flow

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Investigation 3 Go with the Flow
Part 1 Slope
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What formed the Grand Canyon? What processes
were involved?
The Grand Canyon is one place where erosion has
taken place on a grand scale. Geologists are
still trying to figure out how the Colorado River
could have carved such a deep canyon. One idea is
that the slope of the Colorado Plateau became
steeper and caused the canyon to erode faster.
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Todays investigation Does the slope of the
land make a difference in how fast the earth
material erodes?
What do you think? Form a hypothesis.
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• Procedures
• Set up your stream tables according to the
  directions.
• Some groups will investigate a sloped table while
  others will investigate a standard table.
• When your stream starts to flow, record how many
  minutes it took for a major event to
  happen.(erosion, a canyon to form, a delta to
  form, etc.)
• When the water runs out measure and record the
  length and width of your canyon and delta.
• Next, make a map of your stream table on the
  record sheet.

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Follow Up Questions

• What was the first event that you observed?
• When did water start flowing downstream?
• What similarities and differences did you notice
  between the sloped and standard stream tables?
• How did slope affect the time it took for
  landforms to appear?
• What process skills did you use in this
  investigation?

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Word Wall Words Slope-the angle of a stream
channel or land surface Alluvial Fan- a fan
shaped landform deposited at the end of a steep
canyon where the slope becomes flatter.
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Sometimes great thunderstorms near the Grand
Canyon can send huge amounts of water down the
canyon sides. How can we investigate this in our
stream tables? Will a flood cause more erosion?
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• Questions
• How were the results of the flood and slope
  investigations alike?
• How were they different?
• What do think happens to flood waters when they
  reach a larger body of water like a lake?
• What might happen in the Grand Canyon when there
  is a flash flood?
• What differences are there between the standard
  and flood tables?
• How long did it take for features to form in the
  standard and the flood tables? Which causes
  erosion to happen the fastest, the standard or
  the flood?

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Word Wall Words Flood- a very heavy flow of
water, which is greater than the normal flow of
water and goes over the streams normal
channel. Flash Flood- a flood that rises and
falls rapidly with little or no advance warning,
usually as the result of a very heavy rainfall
over a small area.
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• Notes
• Canyons are deeper and the deltas are longer in
  a stream table with a steep slope.
• Water flowing through channels with steep slopes
  causes more erosion.
• Floods erode an unusual amount of earth
  material.
• Floods erode materials more quickly than normal
  water
• flow.
• People can control the flow of water in a river
  with dams, levees, and new channels.