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USGS Unmanned Aircraft Systems (UAS) monitors gas emissions at Mount St. Helens

December 17, 2018

USGS Unmanned Aircraft Systems (UAS) monitors gas emissions at Mount St. Helens in 2018

On September 25, 2018, a team of three scientists based at the Cascades Volcano Observatory conducted the first-ever USGS-led Unmanned Aircraft Systems ("drone") volcanic gas emissions survey at Mount St. Helens. The survey was conducted with the permission and coordination of the U.S. Forest Service Mount St. Helens National Volcanic Monument.

The team used a multi-rotor UAS outfitted with a miniature USGS-developed MultiGAS sensor to measure quiescent gas emissions above the 2004-2008 lava dome within the crater of Mount St. Helens. These new technologies allowed the team to characterize degassing at Mount St. Helens in unprecedented detail.

The UAS survey confirmed that carbon dioxide (CO2) emissions from the 2004-2008 lava dome are extremely low and that water vapor constitutes the vast majority (>99%) of present-day gas emissions. Much of this water vapor is not derived from magma, but instead is produced when shallow meteoric and surface waters, like snow melt, comes into contact with hot dome rocks, generating steam.

The UAS fills an important monitoring role at volcanoes. Its small size and maneuverability allow scientists to use portable monitoring technologies like the MultiGAS, in remote or hazardous areas. The data is combined with that collected using traditional manned aircraft, field sampling, and at a permanent monitoring station, to gain a better understanding of gas emissions at Mount St. Helens. The successful application of these technologies at Mount St. Helens demonstrates the importance of these surveys in the Cascade Range and at other active volcanoes around the globe.

The video is on the USGS YouTube Channel and can be downloaded from the USGS Multimedia Gallery.