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Introduction |
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Yellowstone Park sits
directly over a hot spot. The volcano is quiet today, only the geysers and hot springs
remind us that there is a huge volcano under the beautiful scenery. Only 600,000 years ago
a huge eruption filled the area with lava flows. After the huge eruption there was a void
under the top of the volcano. The weight of the volcano caused the top to come crashing
down forming the large caldera in the park. Since the hot spot remains active, another giant
eruption will almost certainly occur. The question is,
when? |
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Task |
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A new cycle of volcanic
activity has begun. The number and strength of earthquakes have increased; new hot springs
have appeared and existing ones have grown. A large area to the northeast of Yellowstone
Lake has uplifted again. Your group has been hired to present your predictions about
future eruptions. Will it erupt again? If so, when? How much damage will it cause? Each
group member needs to take on a different role and then the group will consult with each
other to prepare the final presentation. The roles are as follows: Seismologist - Collect earthquake activity information around Yellowstone.
Research predictors of other volcanic eruptions, such as Mount St. Helens.
Cartographer - Map the caldera, seismic activity, uplifted regions, and different geyser activity.
Yellowstone Park Official - The person who knows all of the facts
about Yellowstone's caldera and the history of the caldera. |
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Process |
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Seismologist: Magnitude is a
measure of the size of an earthquake. There are a variety of methods used by scientists to
calculate magnitude, the most familiar of which is the Richter magnitude. The Mount St.
Helens volcano reawakened in March 1980 after more than a century of quiet. A magnitude
4.0 earthquake on March 20 was followed by two months of intense earthquake activity.
- Go to the National
Earthquake Information Center (NEIC) and do a rectangular search of seismographic
activity around the Yellowstone Caldera. Use the following parameters: top latitude = 46;
bottom latitude = 44; right longitude = -109.5; and left longitude = -111.5.
- Sort this information however it is the
most useful for you, i.e. by decade, magnitude, etc...
- You may want to graph the information
either in a bar chart, scatterplot, pie chart, or whichever is the most useful for you.
- Find out about seismographic activity as
predictors of other volcano eruptions.
Cartographer: Mount St. Helens intrusion
of vicious magma into the volcano, shoved the north flank outward more than 300 feet and
created the famous 'bulge.' Repeated surveys during April and May showed that the bulge
was growing northward at an average rate of about five feet per day.
- Obtain a map of the Yellowstone Park (there
are several links below that provide maps). The Yellowstone Park Official may be of help
in this area also.
- Find out about the seismic activity in that
region from the Seismologists and create a seismic map. You may want to look at the
seismic maps developed by the University of Utah.
- Also include mapping information about
geyser activities and uplift areas.
- All of this information may appear on one
or more maps.
Yellowstone Park Official: Eruptions
at Yellowstone can produce great volumes (hundreds to thousands of cubic kilometers) of rhyolitic
ash that can cover large areas of the western United States. Because of their rhyolitic
composition, eruptions at Yellowstone are extremely violent.
- Find as much information as you can about
the Yellowstone caldera, i.e. its size, how it was formed, its location.
- Determine when it last erupted.
- Determine how large of an eruption the
Yellowstone caldera can produce, particularly compared to other volcanoes.
- Provide information to the seismologist and
the cartographer as needed.
Whole Group:
- Present to the class your predictions for
the Yellowstone caldera. Have documentation for your predictions and visual aids. See Evaluation below.
- The probability of the caldera erupting in
any particular year can be estimated at 0.000001429% (worse odds than winning the
lottery). Is this the same as 0% probability? Explain.
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Resources |
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These hyperlinks should open
up in a new window so that you can view the URL and possibly investigate some more.
Remember to close windows that you are no longer using. On-line resources:
- VOLCANO HAZARDS FACT SHEET: Yellowstone: Restless Volcanic Giant - provides historical and current information on
the Yellowstone caldera (maps included)
- Yellowstone Caldera's Geologic Setting and Eruptive History
- University
of Utah SEISMICITY MAPS-Yellowstone National Park Region Seismicity Maps
- Volcanic and
Geologic Terms - a comprehensive glossary
- Eruption
scale - how BIG are volcanic eruptions?
- The Snake River Plain and the Yellowstone Hot Spot - provides great
map information and visual magnitude comparison
- Volcanoes of the
United States Online Version 1.1 by U.S. Geological Survey (USGS)
- National
Earthquake Information Center World Data Center A for Seismology Geologic Hazards -
RECTANGULAR AREA search for earthquakes - use the parameters given above
- USGS
Volcano Hazards Program - When is the Volcano Going to Erupt? - provides historical
information on other volcanic eruptions
- Synopsis
of Historical Eruptions in the United States
- Eruptions of Mount St.
Helens: Past, Present, and Future - online edition contains all text from the original
book in its entirety.
- Danger
lurks in Yellowstone Park, especially underneath the earth - By Jon Sarche, Seattle
Post-Intelligencer, September 5, 1996
- Surfing
the Internet for Earthquake Data - Seismosurfing
- VolQuake
(downloadable) is a Microsoft Windows-based computer program designed to facilitate the
study of seismicity associated with volcanic activity. VolQuake software comes with data
sets from Mount St. Helens, Washington (1976-1980), Mount Pinatubo,
Philippines (1991) and Mt. Spurr, Alaska (1992).
Off-line resources (if available):
- Pierce, K.L., and Morgan, L.A., 1992, The track of the Yellowstone hotspot: volcanism,
faulting, and uplift: Geological Society of America Memoir 179, pages 1-53.
- Smith, R.B., and Christiansen, R.L., 1980, Yellowstone Park as a window on the Earth's
interior: Scientific American, volume 242, pages 104-117.
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Evaluation |
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View the Group Presentation Rubric Yellowstone is the largest and
oldest national park system in the United States. Geysers, which occur in very few other
places in the world, occur here in profusion, along with hot springs, steam vents, and
associated phenomena. These are usually the main interests of visitors to the park. Most
people are not aware that Yellowstone is becoming increasingly active and dangerous. While
scientists have yet to fully understand the massive power of the geothermal features of
the park, which are extraordinary and beautiful, the forces can also be life-threatening
and destructive. |
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