8.2 earthquake off Alaska was strong enough to be detected in South Florida and Maine

That 8.2 magnitude earthquake reported off Alaska late Wednesday was powerful enough to be recorded on the other side of the country, according to seismologists.

Subtle “waves” from the quake rolled “across seismic stations in North America” for more than 30 minutes, the Incorporated Research Institutions for Seismology (IRIS) reported Thursday morning.

Seismologists likened the movement to ripples in a pond that grew increasingly faint as they moved south and east, away from the epicenter. The movement was so slight, it was measured in micrometers (microns), officials said.

“Waves from the M8.2 earthquake traveling both through the earth and across earth’s surface ... are much too small to feel but not too small to measure,” IRIS officials said.

The Geological Survey of Alabama was among the first to report its seismic stations had detected the quake. Alabama is about 3,700 miles southeast of where the quake was centered.

“The seismic waves took about 9 minutes to reach the northwestern Alabama seismic stations,” the society reported.

A video released by IRIS shows seismic equipment across the country continued measuring ripples for nearly 35 minutes, and they extended as far south as Florida and as far up the East Coast as Canada.

U.S. Geological Survey officials say the earthquake occurred about 10:15 p.m. local time and was centered off the Alaska Peninsula. Hundreds reported feeling it, including a few witness accounts filed from as far away as in Olympia, Washington, and Cloverdale, Oregon.

The quake “occurred as the result of thrust faulting” between the Pacific and North America tectonic plates,” officials said. The nearest large town was Perryville, Alaska, about 64 miles away.

People in Alaska took to social media to share their experience during the quake, which prompted a tsunami alert that was canceled Thursday morning.

This story was originally published July 29, 2021 at 10:02 AM with the headline "8.2 earthquake off Alaska was strong enough to be detected in South Florida and Maine."