Seismic activity in the Pacific Northwest has been taking place offshore from Oregon as well as in Washington state.

Two earthquakes struck off the Oregon coastline overnight.

The first earthquake struck at 11:10 p.m. on December 28 and registered as a 5.7-magnitude seismic event, according to the U.S. Geological Survey.

At a depth of 10 kilometres (six miles), the epicentre was located 205 kilometres (127 miles) west of Bandon, Oregon; 270 kilometres (167 miles) southwest of Newport, Oregon; and 356 kilometres (221 miles) southwest of Salem, Oregon.

The U.S. Tsunami Warning System stated that there wasn’t a tsunami threat from this quake.

It was later followed by a 3.2-magnitude quake at 2:15 a.m., also a depth of 10 kilometres.

Meanwhile, a cluster of small earthquakes has been taking place in the Bremerton area of Washington state over the past month, including a 3.2-magnitude quake on December 15.

A 3.0-magnitude quake, at a depth of 20 kilometres (12 miles) struck at 6:36 a.m. today (December 29).

The epicentre was located seven kilometres (four miles) northeast of Carnation, Washington; 15 kilometres (nine miles) north of Snoqualmie, Washington; and 107 kilometres (66 miles) northeast of Olympia, Washington.

On December 28, two earthquakes that struck King and Snohomish counties—one was 2.9-magnitude and the other was 2.2-magnitude—were reported as felt.

Meanwhile, a 4.5-magnitude quake occurred west of the northern end of Vancouver Island on December 25.