PORTLAND, Ore. (KOIN) — Mount St. Helens is recharging its magma stores and it is setting off small earthquake swarms, according to scientists with the Cascades Volcano Observatory (CVO).
The findings were also published in a new article in Wired Magazine.
Seth Moran, the scientist-in-chief at CVO, has been studying Mount St. Helens for nearly 30 years. He says Mount St. Helens has a geological pattern of building itself back up after it erupts.
Moran and his team of scientists say they’ve noticed an uptick in earthquake swarms happening beneath the volcano. Recent measurements have recorded nearly 40 small earthquakes per week, which is a sign small amounts of magma have been travelling up the volcano.
“It’s telling us years to decades from now, St. Helens will erupt again,” said Moran.
The May 18, 1980 eruption of Mount St. Helens killed 57 people and resulted in more than a billion dollars in damage. Moran told KOIN 6 that the next eruption won’t be nearly as devastating.
“Our best long term forecast is that the next eruption will be a lava dome building eruption, which will have some explosivity to it, but nothing as catastrophic as St Helens in 1980” he said.
Seismologists recorded a similar pattern of earthquake swarms leading up to the 2004 Mount St. Helens eruption, though those earthquakes were more powerful. Moran said earthquakes measured in recent weeks have been no higher than 1.3 on the Richter Scale. The earthquakes leading up to the 2004 eruption were 2’s and 3’s.
The United States Geological Survey on Friday morning addressed the quakes, saying that they began on March 14.