Sunday, March 13, 2011

Bay of Fundy earthquakes inevitable.

So we are refurbishing a coastal nuclear plant that should not have been sited at Pt. Lepreau in the first place and we cross our fingers for another 50 years? If something happens there, say goodby to our fishing, aquaculture and about everything else that is really worth something. Not smart!! 

Want to argue. I worked on the environmental impacts of the 1952 reactor meltdown at Chalk River. Not good folks.

Incidentally, I understand the CBC stated there are no faults around our nuclear power plants. Not so.

Art.

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Earthquakes fairly common in N.B.

Published Saturday March 12th, 2011

Province sits on Northern Appalachian Seismic Zone, and is known for moderate earthquake activity
A1
BY KRIS MCDAVID
Times & Transcript Staff

New Brunswick has never experienced a devastating earthquake like the magnitude 8.9 behemoth that struck Japan yesterday, and likely never will.

But according to a retired University of New Brunswick geologist who specializes in seismic activity, it's a virtual certainty that our province will experience a quake with potentially destructive consequences within the next 100 years.

Kenneth Burke was glued to his television set and the Internet yesterday, monitoring the crippling tsunami activity that has swept away wide swaths of land, sparked fires, crumbled homes and killed hundreds in the largest earthquake to ever strike Japan.

And although New Brunswickers are fortunate enough to not live in fear of "the big one" striking like citizens of cities like Los Angeles, San Francisco, Seattle and Vancouver, earthquakes are actually a fairly regular occurrence here, with two or three annually being the norm in recent years.

"(Those Pacific cities) are right on the edge of the plates moving past each other and we're right in the centre - we've got cracks that creak and groan, but we don't have a major tectonic boundary in the east here," Burke said.

And as for the likelihood of a major quake ever striking our province, Burke said that while nobody can predict exactly when one might occur, it's almost a given that one will happen - it's just a matter of when, not if.

"In the next 100 years, yes," Burke said. "We've had them in the past, we're going to get them in the future for sure; the earth is still moving and it's good that it is or else we'd be a bit like Mars ... there are good aspects to the movement but you hate to see people killed, obviously."

Most of New Brunswick is situated on what is known as the Northern Appalachian Seismic Zone, which stretches southerly through the New England states.

When they do occur in New Brunswick, earthquakes tend to happen in three distinct regions: the Passamaquoddy Bay, the Central Highlands (Miramichi-Plaster Rock area) and right here in Metro Moncton.

And unbeknownst to many in southeastern New Brunswick, there was actually an earthquake in the region as recently as last month.

"There was a magnitude 2.5 or thereabouts just near Moncton in February - nobody felt it, or somebody might have felt it and just didn't report it," Burke said.

Sure enough, on Feb. 3, a 2.7-magnitude quake was reported by Earthquakes Canada, the Department of Natural Resources wing that monitors seismic activity in Canada, just 10 kilometres north of Sackville.

There were also three minor seismic events, in the range of 1.9-magnitude, that occurred in the vast, remote area between Miramichi and Plaster Rock in February, with nearly 25 minor earthquakes being recorded in New Brunswick between March 2010 and 2011.

The most widely reported of those earthquakes was one that took place near Sussex, a 3.2-magnitude, that caused no damage but stirred up tremors stretching for over 100 kilometres in February.

In the Bay of Fundy, several residents on Deer Island felt a 2.4-magnitude quake in August and in July there was a 3.2-magnitude event near Machias, Maine that was felt lightly in this province.

To put things in perspective, for any instantly noticeable shaking or significant damage to occur as a result of an earthquake the magnitude is usually at, near, or above a 5.0, placing New Brunswick's quakes this past year on a decidedly minor and borderline unnoticeable scale. But even in our recent history, New Brunswick has borne the brunt of a handful of quakes that were indeed noticeable.

The largest of these occurred in January 1982 near Miramichi, registering in at a magnitude of 5.7, luckily centred on an unpopulated area in the Miramichi River watershed located north of Route 108.

Aftershocks of 5.1-magnitude shook the region a day later, with some 80 aftershocks being detected days later by a monitoring station near Edmundston.

Burke says at "the bend" of the Petitcodiac River in Moncton in 1855, what was later believed to be a 5.2-magnitude quake rocked the region and was felt as far away as Boston.

"Moncton was only a little village at the time, and if you look at the newspapers of the day, some of the roads were ripped apart, some parts of the Petitcodiac, and some buildings in Hillsborough were damaged as well," Burke said.

The last Metro earthquake that Burke says "caused any stir" was a magnitude 3.8 in 1988 in the Turtle Creek area, with another 24 smaller seismic events occurring in the Moncton area between 1900 and 1999.

And even though the threat of earthquakes and tsunami warnings are more common in Western Canada, the truth of the matter is that the most devastating earthquake in Canadian history took place in the Maritimes in 1929.

The magnitude-7.2 Grand Banks (Newfoundland) earthquake stirred up angry seas, killed somewhere in the neighbourhood of 29 people, washed away land and swept away homes on Nov. 18 of that year.

The tremors of that event were felt throughout New Brunswick, as were the effects of a 6.2-magnitude quake in the Charlevoix-Kamouraska region of Quebec in March 1925, and the 6.5-magnitude Saguenay earthquake (Quebec) of November 1988.

* To access complete historical earthquake data in Canada, visit the Earthquakes Canada website at http://earthquakescanada.nrcan.gc.ca

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