Two earthquakes have shaken America’s Washington state, with the tremors felt into British Columbia and across the Cascade Mountains into the eastern part of the region.
There were no immediate reports of damage or injuries.
The US Geological Survey reports that a 4.6 magnitude earthquake rattled the Three Lakes area, about 64 kilometres northeast of Seattle. That was followed minutes later by a 3.5 magnitude aftershock near the city of Monroe, about 48km northeast of Seattle.
The initial jolt was recorded at 2.51am local time on Friday. The state Department of Transportation said the agency would be inspecting bridges, but had no reports of damage.
The USGS said it received reports of people feeling the shaking from Vancouver to near Wenatchee, Washington.
Thankfully there are no reported injuries from last night’s #SeattleEarthquake. However, many of us live near the Cascadia Subduction Zone and we must all be ready for more earthquakes in our future. Preparedness starts in every household – know what to do when the next one hits. https://t.co/R4HdvvfdvQ
— Governor Jay Inslee (@GovInslee) July 12, 2019
Further south along the Pacific coast, a magnitude 4.9 aftershock of last week’s Southern California earthquakes was felt widely in the region on Friday morning. There have been thousands of aftershocks of the magnitude 6.4 earthquake on July 4 and the 7.1 quake that occurred the next day.
David Caruso, a USGS geophysicist, told The Seattle Times the Washington state quake was due to a thrust fault, in which one side of a fault pushed upward relative to its opposite side. Such quakes are common in the Cascade Mountain range.
Caruso said the Northwest quake had no connection to the recent earthquakes in California.
Meanwhile, a magnitude 4.9 aftershock of last week’s Southern California earthquakes has been felt widely in the region.
The US Geological Survey says the quake occurred at 6:11am. Friday and was centred about 8kms northeast of the Mojave Desert city of Ridgecrest.
The quake was felt very lightly in the Los Angeles area.
There have been thousands of aftershocks of the magnitude 6.4 earthquake on July 4 and the 7.1 quake that occurred the next day.
The aftershocks have been dying off but are expected to continue for some time. Seismologist Lucy Jones tweets that the 4.9 quake is normal and is having its own aftershocks.
The USGS says the probability of a 7.1 or larger quake has fallen to less than one per cent.
Originally published as Two earthquakes rattle Washington