The Alaska Volcano Observatory later plans to install a series of seismic instruments on Mount Edgecumbe near Sitka. initial measurement Shows magma moving deep beneath a volcano the size of Mount Fuji.
The movement doesn’t mean an eruption from southeast Alaska’s most prominent volcano will happen anytime soon โ or at all โ but it’s significant enough that the observatory has raised the volcano’s threat level.
“Internally, how we think about Edgecumbe has changed. It’s definitely gone up,” said Cheryl Cameron, a state geologist who works at the volcano observatory.
Observatory officials paying more attention to Edgecumbe since april last yearThat’s when a swarm of small earthquakes drew attention to the volcano, which had been thought to be dormant.
A update new informationReleased Friday, Shows Earthquakes Continue, Hikers Have Seen gas bubbling up from the ground near the volcano, and satellite radar measurements show the land around the volcano to be bulging upwards.
“Our latest update is really just saying, ‘Hey, this disturbance is still going on. We still think the magma’s very deep. It might not erupt. If it does erupt, we Let’s expect a lot more activity before that,” said Michelle Coombs, USGS geologist and scientist-in-charge at the Alaska Volcano Observatory.
In one october paper Published in the journal Geophysical Research Letters, scientist Ronnie Graepenthin said the land on the east side of the volcano was erupting outward faster than any other volcano in Alaska.
“Other volcanoes have had a similar amount of deformation without eruption,” Combs said. Maule Lagoon in Chile Erupted outward even more rapidly than Edgecumbe, and for a longer period, without any eruption.
Mount Edgecumbe is now considered a “high” risk volcano, one step below the state’s “very high risk” volcanoes: Augustine, Spur, Redoubt, Akutan and Makushin.
Coombs said the risk isn’t just the possibility of an explosion. It is also based on how close the volcano is to homes, businesses and structures.
Mount Rainier, in Washington state, hasn’t erupted in more than 500 years and shows no signs of doing so, but it is the No. 3 hazard in the country because of the danger it poses to people who live near it.
There are no written accounts of eruptions from Mount Edgecumbe, but Tlingit oral tradition calls L’รบx Shaa (Edgecumbe’s original name) the “glowing, fire and smoke-breathing mountain” about 800โ900 years ago.
Scientific core samples indicate an eruption between 4,000 and 4,300 years ago, with additional eruptions prior to this.
“To a geologist, an eruption 4,000 years ago is very recent, you know?” Combs said.
About 14,000 years ago a series of eruptions spread volcanic ash across Southeast Alaska may have helped melt glaciers which covered the area at that time.
Now, 73,000 people live in this area. Sitka, with a population of about 8,400 people, is 14 miles away.
Don Kluting and his wife, Denise Turley, are among those 8,400 people and frequently travel across Sitka Sound to Krujoff Island, home to Mount Edgecumbe, for hiking and birdwatching.
In October, they found something new โ gas bubbling up through several ponds on the east side of the island.
Turley said that his first thought was that the bubbles were from something rotting in the ponds or from tidal action, but he had never seen them before and considered the bubbles remarkable enough to report to Cameron, who was from the Tlingit and Sitka. Is.
That report prompted the volcano observatory to plan a gas-sampling mission, which could happen as early as May. If gas bubbled up through the lakes, he said, it would be another sign of activity at the volcano.
Around the same time, the observatory will place three or four additional instrument stations on the volcano.
These stations will use GPS to track the volcano’s continued expansion, and their seismographs will allow scientists to triangulate small earthquakes occurring within the volcano as magma moves around.
Cameron said the observatory is also planning a meeting with Sitka residents to explain what’s happening with the volcano.
Partly because of their experience, Kluting and Turley have been following events more closely than most others. They said they are not worried about the volcano’s movement or the remote possibility of an eruption.
“I think I trust the science on this,” Kluting said. “I’ve definitely heard from people who are very concerned and feel like they’re scared. After talking with Cheryl and the crew, I think the surveillance works. I think its There’s science behind it. I think they’re doing due diligence and following through and believe there’s going to be a lot of warning if we ever get to that point, and it may never happen.
