The magnitude 6.5 earthquake felt in Idaho today (March 31) is being recorded as the state’s most significant in almost 40 years.
Previous to this, in 1983, a magnitude 6.9 earthquake shook the state.
“It’s a relatively rare event,” said John Cassidy, earthquake seismologist with Natural Resources Canada.
The ‘surface wave’ quake, which acts like a slow, rolling ocean wave, was felt up to 800 km away, even reaching Calgary.
Cassidy said the earthquake had the potential to be damaging to areas only within 100 km of the source. In areas outside of this, chandeliers shook and high-rises swayed back and forth, however not in a damaging way according to social media.
A magnitude 4.6 aftershock has already been recorded, and Cassidy expects to see more aftershocks to come in the following days.
“I would expect some damage in very nearby communities but certainly not in Canada, and probably not even in Boise (Idaho).”
The earthquake was sourced 72 kilometres west of Challis.
Plate movements in Idaho and Montana, Cassidy explained, are causing a slow separation, or stretching of regions. The plates, which move only one or two centimeters a year, have the potential to cause earthquakes such as these.
“It’s not the biggest event that’s occurred in that area, but it’s a good reminder for people living in an earthquake zone that these events strike without warning,” said Cassidy.
“So being prepared, knowing what to do when the shaking begins which is to drop, cover, and hold on.”
Reports are streaming in on social media after an earthquake shook parts of B.C.’s interior, shortly before 5 p.m.
The US Geological Service is reporting that the earthquake felt in B.C.’s Interior was a magnitude 6.5 tremor in Idaho, about 72 kilometres west of Challis. The earthquake was also reportedly felt in eastern Washington.
More to come.