Strange Sounds 23 Dec 2019
Yesterday, five earthquakes, including two M6.0 jolts, struck off Vancouver Island, British Columbia, Canada.
Now seismologists say Vancouver Island is overdue for a M7.0 earthquake and has entered a period of time where an additional M9.0 mega-thrust rupture earthquake, likely to cause a tsunami, can be expected.
While the region northwest of Vancouver Island’s northern end experiences frequent seismic activity, it has been particularly active yesterday, Dec. 23rd.
A series of five offshore earthquakes took place yesterday morning, ranging from 4.7 – and increasing in intensity to two 6.0-magnitude quakes.
- M5.2 – 166km W of Port Hardy, Canada
- M5.7 – 170km W of Port Hardy, Canada
- M6.0 – 176km W of Port Hardy, Canada
- M6.0 – 163km W of Port Hardy, Canada
- M4.7 – 160km W of Port Hardy, Canada
Meanwhile, a sixth earthquake, a M4.3, has hit the offshore region north of Vancouver on December 23, on Haida Gwaii at 9:32 p.m. at a depth of eight kilometres (five miles).
Like the other quakes, there aren’t any reports of damage and none are expected, and there also isn’t a tsunami threat from this event.
Vancouver Island Overdue for Big Quake
In this part of the world, there are the large Pacific and North American plates, and caught in-between is the Juan de Fuca plate system.
These plates push and grind under and past each other in areas called subduction zones.
Earthquakes are caused and can be tiny or they can be massive, like the 2004 Sumatran earthquake, which ruptured 1,000 kilometres of coastline.
In an earthquake, energy is sent shooting in all directions and it pings around inside the earth making the whole earth vibrate.
The last big Vancouver Island earthquake struck Courtenay in 1946 and measured M7.3 on the Richter scale.
The GSC says quakes of this magnitude should happen every decade, so the Island is about 70 years overdue.
But something even more terrifying is lurking… Seismologists say we have entered the timeframe to expect a magnitude 9 mega-thrust rupture earthquake too.
These Cascadia Subduction Zone earthquakes happen every 200 to 800 years, and the last one occurred 300 years ago.
Big One Creates Tsunami
If it hits magnitude 9, the Big One will cause a tsunami, wreaking havoc on some coastal communities on the Island.
While storms often whip up 100 or 200 metres worth of surface water, tsunamis move the whole water column, several kilometres of water, at over 700 km per hour, close to the speed of a jetplane.
Now, earthquake Canada collaborates with the nearby Institute of Ocean Sciences (IOS), whose world-class programmers and super computers model tsunami effects.
One of the worst-case scenario predicts a 10-meter-high tsunami, wrapping around the Island and being 4 or 5m by the time it hits Victoria, and 1 or 2m when it reaches Vancouver.
And west coast residents will most likely receive only 15-45 minutes of notice for tsunami waves triggered from a Cascadia Subduction Zone earthquake. So be ready or get prepared right now! Read more stories and headlines on Strange Sounds and Steve Quayle. [Straight, Soke News Mirror]
David Wilkerson – Climate Change and Earthquakes