A magnitude 6.8 earthquake hit about 58 miles southeast of Nikolski early Tuesday morning, according to the Alaska Earthquake Center.
Natalia Ruppert, an Earthquake Center seismologist in Fairbanks, said the quake hit at about 2:30 a.m. and was preceded and followed by more seismic activity.
“It triggered a very energetic sequence of aftershocks,” Ruppert said. “The largest aftershock was a magnitude 6.6 — about an hour after the magnitude 6.8 — at 3:40 a.m. today, and we are still recording seismic activity in that cluster.”
The center had recorded about 20 other earthquakes of magnitude 4 and above by about 10 a.m. Tuesday morning, she said.
“This is unusual,” she said. “We normally don’t see such an energetic sequence in such a quick succession.”
There’s no reason for Aleutian Island residents to be alarmed at the moment, according to Ruppert. But there is a small chance this sequence could be followed by a larger earthquake. She said the AEC will continue to monitor the seismic activity.
Ruppert advises that people stay alert and pay attention to earthquake activity in the area in case the sequence develops into something more serious.
No tsunami alert was issued, and as of Tuesday morning, Ruppert said none of the activity was large enough to generate a tsunami.
As of about 2:30 p.m., the U. S. Geological Survey had published 21 felt reports, which are online surveys the public can use to describe the location, intensity and overall effect of earthquakes. Reports were submitted by people in Nikolski, Unalaska and Akutan.