At least 200 tiny tremors hit between Victoria and Seattle on March 12. (@earthquakeguy/Twitter)

200 tremors recorded near Vancouver Island due to ‘tectonic dance’

The tremors were not felt but provide useful information to scientists

At least 200 tiny tremors were noted — not felt — between Victoria and Seattle on March 12.

According to John Cassidy, earthquake seismologist for Natural Resources Canada, the noted tremors are not earthquakes but shaking ground that can easily be recorded and monitored.

“[The wave recordings] look kind of like a windstorm coming in, things start to shake gradually, then they shake off a little more and then it rolls off slowly,” Cassidy explained.

RELATED: ‘Earthquake swarm’ strikes off Vancouver Island for past four days

Typically, Vancouver Island moves towards the Lower Mainland at a rate of approximately one centimetre per year but every 15 months or so, a ‘slip’ is recorded. First discovered by two local scientists, Gary Rogers and Herb Dragert, a tremor and slip event is when the Island ‘slips’ back a few millimetres into the ocean.

“In this region where we see tremors, [the plates] are actually going back and forth like a tectonic dance that Vancouver Island does every 14 or 15 months,” Cassidy noted.

Episodic tremor and slip is a very small, slow slip that occurs more frequently than the massive, sudden shifts that characterize a bigger earthquake. By tracking the number of tremors over a period of days scientists are able to tell if an episodic tremor and slip is occurring. This helps them understand the subduction fault beneath the earth including where it’s locked in place and where it’s storing energy aiding in what to expect during future earthquakes.

RELATED: More than 150 tremors hit Vancouver Island in the past 24 hours

“We know from earthquakes around the world that awareness and preparedness make a huge difference in minimizing the impact of earthquakes,” Cassidy said. “Getting under a table, holding on, being away from windows that might break or chimneys that might collapse.”

Cassidy added there is no need for panic but said these tremors are good reminders about the rock that we live on.

“This is an earthquake zone and earthquakes occur here on a regular basis, but larger earthquakes have occurred here and will occur in the future,” Cassidy said.



kendra.crighton@blackpress.ca

Follow us on Instagram
Like us on Facebook and follow us on Twitter.

Just Posted

Sooke cannabis report does little to answer production questions

Council is trying to get ahead of the issue

Saanich woman runs marathons to make dreams come true

Hempler gutted her way through 122 kms with minimal breaks, to support Help Fill a Dream Foundation

Tsartlip canoe team pulls for international glory in Australia

Geronimo Canoe Club paddles to Victoria to kick-start fundraising

Average housing prices would have to drop by $413,000 for Victoria to become affordable

Alternatively, salaries need to increase to $134,000 per year, more than double current levels

Victoria Weekender: What’s happening this weekend, June 15-16

Car Free YYJ, a barber battle and an Outdoor Discovery Day

Bombers down B.C. Lions 33-23 in season opener

Former Lion Andrew Harris leads Winnipeg with 148 rushing yards

Northern B.C. family remembers murdered Indigenous woman with memorial walk

Still no closure for Ramona Wilson’s family 25 years later

Monkey spotted on late-night jaunt in Campbell River

Conservation officers also apparently looking for cougar in the area

B.C. university to offer mentorship program for former youth in care

Students using the provincial tuition waiver program will soon be able to form a community at KPU

Cyclists competing in one of the toughest bike races on the planet pass through Fernie

Divide riders looking strong as they finish first leg of 4160 km race

You might not know these B.C. records are public

Hired a lawyer to file a civil claim? Those are published online

B.C. bus driver loses case to get job back after texting while driving full bus

An arbitator ruled that Tim Wesman’s phone usage was a “a reckless disregard for public safety”

Revamped B.C. Lions set to battle veteran Winnipeg Blue Bombers

The Lions’ first test of the season will be a big one

Most Read