As earthquakes grow stronger beneath remote Alaska volcanoes, risk of eruption increases
A series of rapidly occurring earthquakes beneath two volcanoes in Alaska's Aleutian Islands this week may mean at least one of them could erupt.
But while scientists are seeing "significant unrest" under the volcanoes and observers are concerned, they don't know for sure what will happen.
“Whether or not this will lead to an eruption is something we can’t say at this point,” John Power, a research geophysicist, told The Associated Press. He's with the U.S. Geological Survey stationed in Anchorage at the Alaska Volcano Observatory.
The two volcanoes, Tanaga and Takawangha, are about 5 miles apart. They're on Tanaga Island, part of the western Andreanof Islands, about 1,250 miles southwest of Anchorage.
Recent earthquakes on Tanaga Island
Quake activity grew stronger beneath Tanaga Volcano on March 8 and below Takawangha Volcano a day later. The Alaska Volcano Observatory has raised the alert levels for both volcanoes to "watch" status.
Where are the volcanoes?
Several earthquakes a minute were recorded under Tanaga Island. The largest quake so far in the series was a magnitude 3.9 beneath Tanaga Volcano.
Satellites and other monitors have not detected any eruptive activity or signs of volcanic unrest.
Ground-based volcano alert levels
Tanaga and Takawangha volcanoes are two of three on Tanaga Island. The third is Sajaka Volcano, in the west. Tanaga Volcano is the tallest:
- Tanaga: 5,925 feet high
- Takawangha: 4,754 feet
- Sajaka: 4,443 feet
Tanaga Volcano last erupted in 1914 and has had three known eruptions since 1763. There no recorded eruptions for Takawangha or Sajaka volcanoes.
Tanaga Island is uninhabited. The closest residential area is Adak, a town with about 170 people on Adak Island, about 65 miles away.
Aircraft could be most affected if one of the volcanoes erupt, the AP reported. Jets commonly fly over the Aleutians, and airborne volcanic ash could present a danger to aircraft engines.
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SOURCE USA TODAY Network reporting and research; Associated Press; Alaska Volcano Observatory