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Comparison of caldera-forming eruption sizes (by volume of erupted magma) in the U.S., modified from an AVO/USGS figure. Also included for reference is the 1980 eruption of Mount St. Helens. The three caldera-forming eruptions in Alaska are more than 200 times the size of the 1980 eruption of Mount St.
Comparison of caldera-forming eruption sizes (by volume of erupted magma) in the U.S., modified from an AVO/USGS figure. Also included for reference is the 1980 eruption of Mount St. Helens. The three caldera-forming eruptions in Alaska are more than 200 times the size of the 1980 eruption of Mount St.
A lahar is a volcanic mudflow. Learn if you are if you are in a lahar hazard zone and how to evacuate to high ground. If you are in a lahar hazard zone and get a lahar alert - go now! Every second matters.
A lahar is a volcanic mudflow. Learn if you are if you are in a lahar hazard zone and how to evacuate to high ground. If you are in a lahar hazard zone and get a lahar alert - go now! Every second matters.
A shaded relief map of Mount Rainier with GPS track from the gas observation flight. The colors correspond to CO2 levels in parts per million by volume (ppmv) that were measured during the flight. Yellow points indicate elevated CO2 levels, which were located near visibly degassing volcanic gas vents.
A shaded relief map of Mount Rainier with GPS track from the gas observation flight. The colors correspond to CO2 levels in parts per million by volume (ppmv) that were measured during the flight. Yellow points indicate elevated CO2 levels, which were located near visibly degassing volcanic gas vents.
Gas sensor packages mounted to the floor of the aircraft near the rear passenger seats, connected to the outside through black tubing that attaches to the window plate, pictured above.
Gas sensor packages mounted to the floor of the aircraft near the rear passenger seats, connected to the outside through black tubing that attaches to the window plate, pictured above.
USGS gas geochemists Christoph Kern (left) and Laura Clor (right) during the airborne gas survey of Mount Rainier.
USGS gas geochemists Christoph Kern (left) and Laura Clor (right) during the airborne gas survey of Mount Rainier.
View from the helicopter cabin showing the connections from the inlet window to the measurement equipment inside.
View from the helicopter cabin showing the connections from the inlet window to the measurement equipment inside.
In this video, Cascades Volcano Observatory (CVO) scientists Tyler Paladino and Alex Iezzi and Mount Rainier National Park Geologist Scott Beason provide an update on the earthquake swarm at Mount Rainier.
In this video, Cascades Volcano Observatory (CVO) scientists Tyler Paladino and Alex Iezzi and Mount Rainier National Park Geologist Scott Beason provide an update on the earthquake swarm at Mount Rainier.
Volcanoes tend to have seismicity that waxes and wanes over time. That’s considered normal and not necessarily a cause for concern. Let’s check on Mount Adams to see what USGS scientists are doing to learn more about its recent earthquake activity and what it could mean for this Cascade Range volcano.
Volcanoes tend to have seismicity that waxes and wanes over time. That’s considered normal and not necessarily a cause for concern. Let’s check on Mount Adams to see what USGS scientists are doing to learn more about its recent earthquake activity and what it could mean for this Cascade Range volcano.
Mt St. Helens before 1980, Land of Transformation
A stylistic interpretation of pre eruption snowcapped Mount St Helens as seen from a blue Spirit Lake with green rolling hills.
Text changes to May 18, 1980, Eruption. There is a grey explosion of rocks and smoke coming out the top of Mt St Helens. The hills and water are grey and brown.
Mt St. Helens before 1980, Land of Transformation
A stylistic interpretation of pre eruption snowcapped Mount St Helens as seen from a blue Spirit Lake with green rolling hills.
Text changes to May 18, 1980, Eruption. There is a grey explosion of rocks and smoke coming out the top of Mt St Helens. The hills and water are grey and brown.
Mt St. Helens before 1980, Land of Transformation
A stylistic interpretation of pre eruption snowcapped Mount St Helens as seen from a blue Spirit Lake with green rolling hills.
Text changes to May 18, 1980, Eruption. There is a grey explosion of rocks and smoke coming out the top of Mt St Helens. The hills and water are grey and brown.
Mt St. Helens before 1980, Land of Transformation
A stylistic interpretation of pre eruption snowcapped Mount St Helens as seen from a blue Spirit Lake with green rolling hills.
Text changes to May 18, 1980, Eruption. There is a grey explosion of rocks and smoke coming out the top of Mt St Helens. The hills and water are grey and brown.
The May 18, 1980, eruption of Mount St. Helens was historic and fundamentally changed how we see volcanoes. For those who lost family and friends, homes, and their livelihoods, it was an unimaginable tragedy. For others around the world, the eruption was an exciting curiosity, an experience they could share with their kids and grandkids.
The May 18, 1980, eruption of Mount St. Helens was historic and fundamentally changed how we see volcanoes. For those who lost family and friends, homes, and their livelihoods, it was an unimaginable tragedy. For others around the world, the eruption was an exciting curiosity, an experience they could share with their kids and grandkids.
The May 18, 1980, eruption of Mount St. Helens was historic and fundamentally changed how we see volcanoes. For those who lost family and friends, homes, and their livelihoods, it was an unimaginable tragedy. For others around the world, the eruption was an exciting curiosity, an experience they could share with their kids and grandkids.
The May 18, 1980, eruption of Mount St. Helens was historic and fundamentally changed how we see volcanoes. For those who lost family and friends, homes, and their livelihoods, it was an unimaginable tragedy. For others around the world, the eruption was an exciting curiosity, an experience they could share with their kids and grandkids.
Welcome to CoreFacts, where we're always short on time and big on science. I'm Brian Campbell. Today's question is …
How far did the ash from Mount St. Helens travel?
Welcome to CoreFacts, where we're always short on time and big on science. I'm Brian Campbell. Today's question is …
How far did the ash from Mount St. Helens travel?
Listen to hear the answer.
This static image is from a USGS Cascades Volcano Observatory research camera located at the Johnston Ridge Observatory, north of Mount St. Helens. The view is to the south. This camera is intended to assist the USGS with situational awareness. At times, clouds, rain, and snow obscure visibility.
This static image is from a USGS Cascades Volcano Observatory research camera located at the Johnston Ridge Observatory, north of Mount St. Helens. The view is to the south. This camera is intended to assist the USGS with situational awareness. At times, clouds, rain, and snow obscure visibility.
