Scientists from the USGS Cascades Volcano Observatory (CVO) and the Pacific Northwest Seismic Network (PNSN) who are monitoring Mount St. Helens in Washington confirmed that the volcano is showing signs of activity, but an eruption is not expected to happen anytime soon.
Researchers found out that the volcano's magma reservoir has been re-pressurizing the material since 2008. The reservoir is approximately five miles underneath the volcano. The scientists noticed that fresh molten rock is slowly filling the reservoir again, after the volcano’s eruption in 2008.
"This is giving long-term (data) that it's getting ready to erupt again, but it could be decades before it does something again," volcano seismologist with the U.S. Geological Survey Seth Moran told the Associated Press."It's getting ready but it's not there."
On May 18, 1980, Mount St. Helens’ eruption killed around 57 people and destroyed 250 homes, 47 bridges, railways and highways. It also devastated the forest and filled both rivers and the sky with volcanic ash and debris. The event was considered the deadliest and most economically destructive volcanic event in the history of the United States.
Moran explained that the slow uplift of the magma is gradual and steady. The current increase in height has measured to about the length of a thumbnail in the past six years. The current observed activity mirrors that of the volcano's characteristics prior to the 1980 eruption.
On the other hand, spokeswoman of the USGS Cascades Volcano Observatory Carolyn Driedger explained that these signals are very minute, but they still have to be monitored and studied. The signals were detected by scientists through the expansive network of GPS and seismic monitors installed in the periphery of the volcano.
Moran further explained that the slow activity and refilling of the reservoir could be seen as the volcano’s way of recharging its chambers.
"It may stay perched at ready stage for a long time before it starts to erupt. The reassuring thing is: when it's really ready to erupt; it gives lots and lots of signs,” Moran told the Associated Press.
The USGS and PNSN will be conducting two surveys this summer to measure the amount of volcanic gases emitted and the strength and gravity field of the volcano. Updates will be posted on their website.
