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

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

North Saanich has received a report from the Urban Development Institute calling on the municipality to expand and densify its housing options in the face of demographic and environmental changes as the municipality continues its Official Community Plan review. (Black Press Media file photo)
North Saanich asked to create more affordable, diverse housing

Urban Development Institute says community faces demographic, environmental challenges

The orange parcel was bought by the CRD for $1.1 million to add to Mount Work Regional Park. (CRD map)
Capital Regional District expands Mount Work land for $1.1 million

Privately-owned 13.8 hectares in the Highlands is ecologcically valuable

One woman has been arrested in connection with a drug trafficking investigation. (Black Press Media file photo)
Victoria woman arrested, car and drugs seized during trafficking investigation

Multiple units combine forces for investigation, arrest

Dog trainer Sharon Labossiere at play with her dogs. AnimalKind, the BC SPCA’s animal welfare accreditation and referral program, has granted accreditation to Sooke's Hanging with Hounds. (Contributed - BC SPCA)
Hanging With Hounds digs its paws into AnimalKind accreditation

Local dog trainer earns special BC SPCA status

Royal Bay Secondary School’s rainbow crosswalk was vandalized shortly after being painted but by Monday, coincidentally the International Day Against Homophobia, Transphobia and Biphobia, the crosswalk had been cleaned up and students had surrounded it with chalk messages of support and celebration. (Zoe Ducklow/News Staff)
Royal Bay pride crosswalk restored following graffiti attack

Hate terms, racial slur, phallic images spray-painted at Colwood high school

An avalanche near Highway 1 in Glacier National Park. Avalanche Canada will benefit from a $10 million grant from the B.C. government. (Photo by Parks Canada)
Avalanche Canada receives $10-million grant from B.C. government

Long sought-after funds to bolster organization’s important work

More “strings of lights” were seen on May 15, 2021, in night sky over Vancouver Island. (File photo)
Sicamous RCMP Sgt. Murray McNeil and Cpl. Wade Fisher present seven-year-old Cody Krabbendam of Ranchero with an award for bravery on July 22, 2020. (Contributed)
7-year old Shuswap boy receives medal of bravery for rescuing child at beach

Last summer Cody Krabbendam jumped into the lake to save another boy from drowning

B.C. Health Minister Adrian Dix and provincial health officer Dr. Bonnie Henry update the province’s COVID-19 vaccine program, May 10, 2021. (B.C. government)
B.C.’s COVID-19 infection rate stays below 500 a day over weekend

14 more deaths, down to 350 in hospital as of Monday

Royal Bay Secondary School’s rainbow crosswalk was vandalized shortly after being painted but by Monday, coincidentally the International Day Against Homophobia, Transphobia and Biphobia, the crosswalk had been cleaned up and students had surrounded it with chalk messages of support and celebration. (Zoe Ducklow/News Staff)
B.C. high’s school’s pride crosswalk restored following ‘hateful’ graffiti attack

Hate terms, racial slur, phallic images spray-painted at Greater Victoria high school

Terrance Mack would have celebrated his 34th birthday on May 13, 2021. Mack’s family has identified him as the victim of a homicide in an apartment on Third Avenue in Port Alberni sometime in April. (SUBMITTED PHOTO)
Family identifies Ucluelet man as victim of Vancouver Island homicide

Terrance Mack being remembered as ‘kind, gentle’ man

Nathan Zuk had left his mother’s residence in Whaletown on Cortes Island in mid-December 2020 in a 14’ skiff rowboat and headed to an unknown location near the Pryce Channel, Deer passage, or Toba Inlet. Photo courtesy RCMP
RCMP need help finding man who set off from Cortes Island in 14-foot rowboat

Nathan Zuk left in December, may have been last seen in Toba Inlet approximately three weeks ago

Emergency service workers at the collision scene along Highway 4 in Hilliers on Sunday, May 16. A motorcyclist was airlifted to hospital by BC Air Ambulance and later died. (Collin C photo)
UPDATE: Motorcyclist dies from injuries sustained in Mid-Island highway collision

BC Highway Patrol says impairment not a contributing factor in crash

An avalanche near Highway 1 in Glacier National Park. Avalanche Canada will benefit from a $10 million grant from the B.C. government. (Photo by Parks Canada)
Avalanche Canada receives $10-million grant from B.C. government

Long sought-after funds to bolster organization’s important work

Most Read