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Cascade Range Weekly Update
Friday, March 23, 2018 11:13 AM US/Pacific
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN
Cascades Volcano Observatory's mission
The U.S. Geological Survey's Cascades Volcano Observatory strives to serve the national interest by helping people to live knowledgeably and safely with volcanoes in WA, OR, and ID.

HOT STUFF   (archive)
Young Volcanoes in WA, OR & ID1

Registration is open for Mount Rainier teacher training in the Park.
March 21, 2018

Mount Rainier National Park is a unique classroom, rich in resources for observing geologic change. Join us July 23–27, 2018, for a 5-day educator workshop in the Park, where we will explore the diverse and dynamic processes that have shaped the volcano and share new classroom ideas that will engage middle school students. There is a $20 fee for this workshop and free camping is available to participants. Registration information is at the Mount Rainier Teacher Professional Development webpage.

New video describes SNIF volcanic gas monitoring station at Mount St. Helens.
March 15, 2018

Scientists at the USGS-Cascades Volcano Observatory developed a MultiGAS analyzer to continuously monitor gas plumes at Mount St. Helens. Take a tour of the crater and the "SNIF" station in this new 7-minute video narrated by USGS-CVO Research Geologist Peter Kelly.

While Mount St. Helens is currently at normal background levels of activity, by continuously monitoring volcanic gases at Mount St. Helens and other volcanoes, scientists hope to pick up on the earliest signs of unrest. The data will be used in combination with other monitoring data such as seismicity and ground deformation to piece together a comprehensive model for what we think is going on at the volcano. The information will be used to issue warnings of impending eruptions and deliver eruption updates to local governments, public officials, the media and the public.

Watch the video Continuous Gas Monitoring Tracks Volcanic Activity at Mount St. Helens or download from the USGS Multimedia Gallery.

Scientists offer interactive Volcano Explorer webinars for middle school students.
January 29, 2018

In March, scientists with the Volcano Disaster Assistance Program and Cascades Volcano Observatory will participate in live, interactive video presentations with middle school students. The program is organized by the USGS–Cascades Volcano Observatory and the Mount St. Helens Institute.

  • March 6, 2018: How can we measure a mountain? Angie Diefenbach, a geologist with the USGS Volcano Disaster Assistance Program, talks about how scientists measure changes at a volcano using drones, cameras, and satellite technology.
  • March 13, 2018: Eruption forecasting requires scientists to work together to make the best interpretation possible. Heather Wright, a geologist with the USGS Volcano Disaster Assistance Program, talks about her experiences working with scientists from other countries to monitor volcanoes and prepare for eruptions.
  • March 20, 2018: What can we learn from rivers of mud? Richard (Dick) Iverson, a research hydrologist with the USGS–Cascades Volcano Observatory, talks about how he makes his own debris flows and releases them down a 310-foot-long debris flow flume to study what happens to the flows. He also uses computer simulations to understand how debris flows form and travel. His work is used to assess debris-flow hazards and to help design technologies that are used to mitigate the hazards, including automated detection and warning systems and engineering countermeasures that protect people in high-risk areas.

All classes are welcome to attend. The presentations are aimed at 5th – 8th grade students who study earth history, landforms or geologic processes. For more information on how to register for the free webinars, visit the Mount St. Helens Institute Volcano Explorers webpage.

A new study weighs in on processes occurring beneath Mount St. Helens.
January 19, 2018

A USGS research study published in the American Geophysical Union's Solid Earth sheds light on processes occurring beneath Mount St. Helens.

Measurements at a dozen sites on the volcano during 2010–2016 show a small but steady increase in the strength of Earth's gravity field. The change indicates that material has been added beneath the volcano since the end of the 2004–2008 dome-forming eruption. The gravity increase could be caused by groundwater accumulating in a shallow aquifer that was partly boiled off during the eruption, or by addition of magma to the reservoir-conduit system that fed the eruption, or by a combination of both processes. Of these options, a small influx of magma is consistent with post-2008 seismicity that suggests re-pressurization of the magma system since the eruption ended, something also indicated by geochemical data from hot springs and fumaroles. These results suggest that, although there is no indication of an imminent eruption, the Mount St. Helens magma system remains active and could conceivably erupt again on a time frame of years to decades.

Gravity measurements are another tool used by scientists at the USGS–Cascades Volcano Observatory to better understand volcano behavior and improve eruption forecasts. The gravity surveys provide information about subsurface changes in mass (water or magma) that cannot be obtained by other methods. The results are being combined with data about earthquakes, ground deformation, hot springs, and gas emissions to develop an ever sharper picture of processes that are hidden underground from direct observation.

USGS–CVO continuously monitors activity at Mount St. Helens, along with other Washington and Oregon volcanoes, and provides information and Updates. Read more about repressurization at Mount St. Helens in an Information Statement released April 30, 2014.

Geologic maps lay the foundation for this virtual tour of western states volcanoes.
January 09, 2018

What do the Three Sisters, Crater Lake, Medicine Lake, Lassen Peak, Mammoth Mountain and Yellowstone have in common?

Each of these volcanoes has been studied extensively in order to produce comprehensive geologic maps. The results of these studies are more than just maps—each is a synthesis showing a volcanic field's eruptive history and the volcano's behavior over its lifetime. These studies form the foundation for future assessments of volcanic or geologic activity and geohazards.

Take a virtual geologic tour in the USGS Geonarrative, Volcanic Landscapes.

CVO welcomes the public to an Open House on May 12, 2018.
December 14, 2017

The USGS-Cascades Volcano Observatory opens its doors to the public on Saturday, May 12, for a one-day open house. Scientists will be on-hand from 10:00 am to 5:00 pm to share the results of their research and talk about volcano hazards. Hands-on activities and equipment demonstrations will be featured.

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