Sunday, March 13, 2011

Montreal , Vancouver Would Crumble

             Now we will hear everywhere how susceptible we really are to potential earthquakes etc etc .....  but could you imagine an 8.9 in Montreal,although in all the time I lived in Montreal I only remember experiencing 1 tremor ,since I've been on the Westcoast ,I've felt plenty of them ,some very minor ,some that got your attention.I doubt you can really be 'ready' for something as catastrophic as a 9.o quake & then a Tsunami, but I suppose it's nice to 'think' you are ready...Japan is one of the 'most ready' peoples on the planet for earthquake,.ask them today while some of their Nuclear Plants are nearing Meltdown,if they were indeed 'ready' for this...Hmmmm I doubt we are ever ready.               Vancouver and Montreal are in active earthquake zones. And because both are full of buildings that are not up to modern seismic standards, they would sustain heavy damage in a major tremor which is sure to occur some day.

Alena Barner, a mother of two who rents in a mid-1960s, concrete apartment building in Vancouver, started to wonder about safety following the deadly quake in New Zealand. So she went to city hall and asked to speak to several engineers. Thursday’s massive quake in Japan has only heightened her concerns.

City staff refused to share information about her building’s safety, saying she would have to talk to the owner. She eventually found an expert and in an email exchange he told her that based on her description of the structure, it would likely crumble.

Mayor Gregor Robertson hinted as much following the Japan’s devastating quake, conceding to CTV News that not enough has been done to reinforce privately owned, older buildings in the city.

A spokesperson for the city said Friday that since 2001, all new one- or two-family dwellings in Vancouver have to incorporate seismic resistance.

In addition, for more than 10 years now, renovation permits for such buildings, as well as apartments, have required seismic upgrades.

Both these requirements are unique to Vancouver among B.C. jurisdiction, said the spokesperson. And they do nothing to ensure older buildings are safe.

Perry Adebar, a professor of structural engineering at the University of B.C., said the biggest issue is that there is no mechanism in place to inspect these older buildings. The only time they are inspected, he explained, is when they are being converted, say from an office tower to condos.

“There are lots of buildings out there that we built decades ago when we knew a lot less than we know now,” he said. “We need to have some process where we start to look at them and just identify the ones that we know are very bad and do something about those.”

According to a 2010 study by a non-profit research agency established by the insurance industry, Montreal is second only to the Lower Mainland in terms of its vulnerability. And there is a five to 15 per-cent chance a damaging earthquake will hit the city in the next 50 years.

In Montreal, half of all structures predate stringent 1971 building codes that include standards for seismic protection. And the fragile nature of the province’s infrastructure has also become evident even without an earthquake — think overpasses that collapse.

The Quebec government, for example, decided last year to close a hospital in Baie St. Paul, northeast of Quebec City, because it wouldn’t endure even a 6.0 magnitude earthquake.

B.C. is spending billions to earthquake-proof every school in the province along with other public buildings. Quebec is just starting to think about it.

“We’re playing catch-up here in Quebec, and we have a long way to go,” said Denis Mitchell, a professor in the department of Civil Engineering at McGill University.

Brick facades and unreinforced masonry are particularly susceptible, as are buildings built on clay, said Mitchell, who is also a program leader of the Canadian Seismic Research Network.

“Typically, we’re talking about areas along the riverbanks,” said Mitchell.

“In 1988, we had the Saguenay (Que.) earthquake, which was only a magnitude 5.9, but the Montreal East City Hall 350 kilometres away was severely damaged because it was right down near the river where there was soft soil. If that earthquake had been bigger, we would have had real problems.”

   ......Have a look at this map of how far the Tsunami spread from Japan across the Pacific (have you ever seen the Pacific ,it's not exactly the English Channel) Places al the way down the Westcoast of North America ,down to Central & South America ,felt the Tsunami and in some places it caused a lot of damage too....that's a powerful wave.Yikes !!


Les F said...

Try to imagine your own neighbourhoods with almost every house on fire or gone,and large buioldngs crumbling would be pretty wild stuff no doubt.

Just a random sampling of some of the effects of the Japan Disaster.......and it's not over yet,those Nuclear Power Plants are in danger too...................

Les F said...

Japan moved EIGHT (8) FEET, that possible:
Quake moved Japan by 8 feet: USGS
(AFP) – 16 hours ago

WASHINGTON — Japan's recent massive earthquake, one of the largest ever recorded, appears to have moved the island by about eight feet (2.4 meters), the US Geological Survey said.

"That's a reasonable number," USGS seismologist Paul Earle told AFP. "Eight feet, that's certainly going to be in the ballpark."

Friday's 8.9 magnitude quake unleashed a terrifying tsunami that engulfed towns and cities on Japan's northeastern coast, destroying everything in its path in what Prime Minister Naoto Kan said was an "unprecedented national disaster."

The quake and its tectonic shift resulted from "thrust faulting" along the boundary of the Pacific and North America plates, according to the USGS.

The Pacific plate pushes under a far western wedge of the North America plate at the rate of about 3.3 inches (83 millimeters) per year, but a colossal earthquake can provide enough of a jolt to dramatically move the plates, with catastrophic consequences.

"With an earthquake this large, you can get these huge ground shifts," Earle said. "On the actual fault you can get 20 meters (65 feet) of relative movement, on the two sides of the fault."

He said similar movements would have been seen for Chile and Indonesia.

In December 2004, a 9.1 magnitude quake off Sumatra caused a tsunami that killed an estimated 228,000 people. An 8.8 quake off the coast of Chile in February 2010 killed more than 500.

There was not a similar ground shift in the 7.0 earthquake that devastated Haiti in February 2010, Earle said.

"A magnitude 7.0 is much smaller than the earthquake that just happened in Japan," he said. "We've had aftershocks (in Japan) larger than the Haiti earthquake."

Kenneth Hudnut, a USGS geophysicist, said experts read data including from global positioning systems to determine the extend of the shift.

"We know that one GPS station moved (eight feet), and we have seen a map from GSI (Geospatial Information Authority) in Japan showing the pattern of shift over a large area is consistent with about that much shift of the land mass," he told CNN.

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