Physical geology exercise: Exploring volcanic activity
Part 2 Monitoring Volcanic Activity - Mt/ St. Helens case study
Like any other active volcano, mounts St. Helens need to be closely monitored in order to assess the level of activity and the likelihood of an eruption. Go to: http://volcanoes.usgs.gov/volcanoes/st_helens/st_helens_monitoring_16.html
For each monitored parameter, summarize the information provided by the monitoring
Earthquakes
Deformation and topographic changes
Image Analysis and Thermal imaging
Volcanic Gas
Rock Analysis
Hydrology
Part 3: Volcanic Hazards
Volcanic activity may hinder or compromise human life or interest, so volcanic activity is often recognized as a geologic hazards. The United States Geological Survey runs the volcanological observatories of the US and it is part of the World Organization of Volcanological Observatories.
The international community recognizes found levels of Alert that are meant to inform people on the ground about volcanic activity. The Alert levels are issued in conjunction with the Aviation alert code because aircraft is especially vulnerable when flying into dispersed volcanic ash, virtually invisible to the radar onboard. Alert codes are summarized in the table below:
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Volcano Alert Level
Land Based
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Normal
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Advisory
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Watch
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Warning
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Volcano is in typical background, noneruptive state
or, after a change from a higher level,
volcanic activity has ceased and volcano has returned to noneruptive background state.
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Volcano is exhibiting signs of elevated unrest above known background level
or, after a change from a higher level,
volcanic activity has decreased significantly but continues to be closely monitored for possible renewed increase.
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Volcano is exhibiting heightened or escalating unrest with increased potential of eruption, timeframe uncertain,
OR
eruption is underway but poses limited hazards.
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Hazardous eruption is imminent, underway, or suspected.
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Aviation Color Codes
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If possible Specify Plume height
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Green
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Yellow
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Orange
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Red
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4 - Visit the USGS Volcano Hazard page at: http://volcanoes.usgs.gov/. Answer the following questions:
a) How many volcanoes are reported on Orange or Red alert? How many on Yellow?
b) Where are these volcanoes located? Use the mute map of the World to mark the position of the volcanoes currently on high level of alert.
Volcanoes of the world
The Global Volcanism Program of the Smithsonian Institution in collaboration with the United States Geological Survey publishes a weekly bulletin of ongoing volcanic activity. Visit the page:
http://volcano.si.edu/reports_weekly.cfm
5 - Choose a volcano from those actively erupting this week. Make sure it is a volcano you NEVER heard about before (learn something new!). Chick on the symbol to access the volcano info page and answer the following questions
a) What is your volcano name?
b) Where is it located? (give latitude and longitude as well as the name of the island, region and Nation in the World).
c) What type of volcano is this? (summarize the description)
d) Briefly summarize the most recent activity. What is the volcano doing, when was its most recent eruption?
e) What type of eruptions normally occur here?
f) When did it erupt last time?
g) Are other volcanoes found nearby? What type of structure is responsible for this volcanism, a plate boundary or a hot-spot?