ANCHORAGE, Alaska — As of this year, there have been more earthquakes under a volcano near Alaska’s biggest city. This has scientists interested.
Mount Spurr is located about 129 kilometers (80 miles) northwest of Anchorage. It last erupted in 1992, sending an ash cloud about 12 miles (19 kilometers) into the air, which caused people to wear masks and flights to be canceled. The Alaska Volcano Observatory says that if the 11,100-foot (3,383-meter) stratovolcano erupts again, it could cause a lot of problems for the city.
In October, the observatory changed Mount Spurr’s warning level from green to yellow because of a clear rise in seismic activity and the discovery of ground deformation in satellite data. Thursday, David Fee, an observatory scientist, said that this year there have been about 1,500 small earthquakes below the volcano. Usually, there are only about 100 in a year.
That may seem like a lot, but Fee said it’s “not an enormous amount.” It might be a sign of an explosion coming up, or it might not. From 2004 to 2006, there was similar earthquake activity that went away without an eruption.
Fee said, “We don’t see any big changes in our data that would lead us to believe that an eruption is about to happen.” “There’s been a low level of unrest for a while now, and we’re keeping a close eye on it to see if anything changes and what that might mean.”
Scientists are keeping an eye on a webcam, seismic stations, and world satellite data to see if there are any other changes that could mean an eruption is about to happen. If magma is moving closer to the surface, there will be more earthquakes, ground deformations, mountain lakes, and fumaroles, which are openings in the surface that let gas and vapors escape.
From the Crater Peak flank vent, which is about 2 miles (3 km) south of the peak, the volcano last erupted in 1992. That year, the eruption dumped about a quarter-inch of ash on Anchorage. People had to stay inside or wear masks when they went outside, and the cloud went as far as Greenland.
In 1953, there was another explosion like this one from the same vent. It’s been over 5,000 years since the last explosion from the top.
Ashes from volcanoes are rough and pointy, and they have been used as abrasives in industry. The fine rock can stop a jet engine, which is why Anchorage and other nearby airports had to close during the 1992 explosion.
When a state doesn’t have many roads, closing airports is always a pain, but it can be more than that. It would also affect business, since Anchorage airport is one of the biggest cargo hubs in the world, along with Memphis, Hong Kong, and Shanghai. This is mostly because Alaska is close to Asia.
Mount Spurr is one of 53 volcanoes in Alaska that have erupted in the last 250 years. It is on the Volcanic Ring of Fire.
