Click
here for a higher graphics version
Before classroom use,
download movies (1&2)
&stacks to HD to save time.
Investigation of Hot Spots
Learner Outcomes
By completing these activities, the learner will:
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view computer models of mantle convection
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investigate stationary mantle plumes
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use NIH image to determine the size of geologic formations
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measure the rate of formation of Hawaiian Islands
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study geologic formations in Yellowstone National Park
Exploration
Watch the convection movie. In groups,
discuss what you see and relate it to what you know about convection.
Watch the movie of the mantle plumes.
Discuss what you see and how it relates to the convection movie. (Note:
The blue areas are descending, and the red areas are ascending.)
Concept Introduction - The Yellowstone Caldera
Open the Yellowstone Caldera TIFF
file and open the file in NIH Image. (Print these
directions).
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Click in the scale to fit window box located in the upper right-hand corner
of the image.
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Click on the line tool.
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Place the "cross-hair" on the left hand end of the scale line which is
located in the lower, right-hand corner of the image.
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Press and hold the mouse button and drag the "cross-hair" to make a line
which matches the length of the scale line.
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Go to Analyze- options and toggle the "Perimeter/Length" option on. All
other options should be toggled off.
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Go to Analyze-set scale
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The Measured Distance should be close to 86 pixels
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Enter 16.129 in the "known distance" box (This number is found
by dividing 1 mile by .62 kilometers and multiplying by the scale
distance of 10 miles.)
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Select Kilometers for the units.
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You do not need to change any of the other menu options. (the magnification,
pixel aspect ratio, and set scale are automatically calculated)
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Go to Analyze-measure, then Analyze-show results. The number
in the box is the length of the line in kilometers. (It should be
close to 16.13.)
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Now measure the length and width of the caldera. (The length of the
caldera is approximately 64 km and the width is approximately 44 km)
If you did not get a measurement close to this, try the procedure again.
If you are not close this time, get assistance.
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Go to File-print measurements.
Concept Application -Hot Spot Tracks
Use NIH Image to open the Hot Spot
Track stack of past
Yellowstone caldera
locations to (Print these directions):
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Animate the stack Windows-animate (Found under Resources-"step
by step")
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Determine the speed of plate movement in cm/yr by measuring the distance
between the calderas and dividing the distance by the difference in the
years between the calderas. (Approximately 5 cm/year) This was determined
by using the following procedure:
-
Click in the scale to fit window box located in the upper right-hand corner
of the image.
-
Click on the line tool.
-
Place the "cross-hair" on the left hand end of the scale line which is
located in the upper, right-hand corner of the image.
-
Press and hold the mouse button and drag the "cross-hair" to make a line
which matches the length of the scale line.
-
Go to Analyze- options and toggle the "Perimeter/Length" option
on. All other options should be toggled off.
-
Go to Analyze-set scale.
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The Measured Distance should be close to 85.71 pixels.
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Enter 161.29 in the "known distance" box (This number is found by dividing
1 mile by .62 kilometers and multiplying by the scale distance of 100 miles.)
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Select Kilometers for the units.
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You do not need to change any of the other menu options. (the magnification,
pixel aspect ratio, and set scale are automatically calculated)
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Go to Analyze-measure, then Analyze-show results. The number in the box
is the length of the line in kilometers.
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Go to File-print measurements. Now measure the distance from the front
edge to the back edge of the caldera
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Go to File-print measurements. Calculate the movement of the caldera (using
the printout of your measurements) for that time period.
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From the 12.5 to 10.3, the measurement is 211.36 km over 2,200,000 years.
By division that is 0.000096 km per year, or 9.6 cm per year. (s = d/t)
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Make a best "guess" as to the age of the caldera with "?" in it based on
the distance between the calderas and the speed of the plate motion that
you came up with. (Remember that crustal movement was greater then,
when compared to more recent movement).
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Using the speed that you obtained from step 7, predict where YNP caldera
will be in 1 million years.
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Predict when YNP caldera will be located near Lewistown, Montana (located
at the geographic center of Montana)
Extensions
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Check out the Classroom
of the Future's module on the Yellowstone Caldera.
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Use NIH image to measure the perimeter and area of the Yellowstone
Caldera.
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Use NIH image to measure the length, width, perimeter and area of the Caldera
in miles.
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Use NIH image to measure aspects of some prominent features of Yellowstone
Park.
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Use NIH image to predict when Yellowstone Park is going to be in Canada.
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Discuss the mechanism that causes the park features to appear to move.