AVO

Updated 06/15/2020 at 7 p.m.

A magnitude-4.2 earthquake occurred under Makushin Volcano Monday afternoon and was felt in Unalaska.

At around 2:16 p.m., an earthquake at a depth of about five miles hit approximately six miles southeast of the volcano's summit, according to the Alaska Volcano Observatory. Small aftershocks are continuing, as is typical for an earthquake of this size.

An explosion at one of Alaska's most active volcanoes has led scientists to raise its alert level to "watch." This comes after the Alaska Volcano Observatory (AVO) lowered Cleveland Volcano's alert level in early May after nearly a year and a half of inactivity.

Cleveland is located on an uninhabited island in the central Aleutians, west of Umnak Island. Around 10:30 p.m. on Monday, the AVO detected a small explosion that sent an ash plume 22,000 feet, traveling to the south.

A magnitude-4.7 earthquake hit the Fox Islands early Monday morning and was felt in Unalaska.

According to the Alaska Earthquake Center (AEC), at 12:21 a.m. an earthquake at a depth of about 53 miles hit 26 miles southeast of Unalaska. 

Natalia Ruppert, a seismologist with the AEC, said the quake was not unusual for the region.

"Last night's M4.7 occurred within a known source of earthquake activity," said Ruppert.

A magnitude 3.5 earthquake occurred at Great Sitkin Volcano on Friday.

Since then, seismic activity has returned to lower levels, and no eruptive activity has been detected at the volcano – located 26 miles east of the community of Adak.

Hans Schwaiger, a scientist with the Alaska Volcano Observatory (AVO), said it appears the shallow earthquake was an isolated event, although small local earthquakes have continued over the past day.

Following a series of flight-canceling explosions, activity at Shishaldin Volcano has decreased over the past three weeks.

Matt Haney, a geophysicist with the Alaska Volcano Observatory (AVO), said this marks a pause for the eastern Aleutian volcano's eruptive phase, which has been underway since late last year.