Largest earthquake to hit Alaska's North Slope region followed by powerful aftershocks

by Craig Takeuchi on August 13th, 2018 at 10:55 AM

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Alaska's North Slope was shaken by the largest-ever recorded earthquake in the region, followed by numerous strong aftershocks.

A 6.4-magnitude earthquake hit at 6:56 a.m. (PT) on August 12. (Initial measurements reported it as 6.5-magnitude.)

The epicentre was located 544 kilometres (338 miles) northeast of Fairbanks, Alaska, and 1099 kilometres (683 miles) northwest of Whitehorse, Yukon at a depth of 10 kilometres (6 miles).

It was the largest seismic event ever recorded north of the Brooks Range in Alaska, according to the Alaska Earthquake Centre.

An extremely active series of aftershocks followed.

6.0-magnitude quake at 1:15 p.m. on August 12

Among the more powerful aftershocks was one that measured 6.0-magnitude that struck at 1:15 p.m. on the same day. (Preliminary measurements initially recorded it as 6.1-magnitude.)

The epicentre was located 546 kilometres (339 miles) northeast of Fairbanks, Alaksa, and 1075 kilometres (668 miles) northwest of Whitehorse, Yukon, at a depth of 11.7 kilometres (7.3 miles).

Another major aftershock followed shortly thereafter at 1:30 p.m., measuring 4.9-magnitude. (It was initially reported as 5.4-magnitude.)

The epicentre was located 534 kilometres (332 miles) northeast of Fairbanks and 1063 kilometres (661 miles) northwest of Whitehorse, at a depth of 0.1 kilometres (0.06 miles).

Seismic activity is continuing today (August 13), including three quakes that measured 4.8, 4.6, and 4.5.