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强烈要求版主置顶数日
鉴于消息比较敏感，避免造成恐慌，我还是直接引用原文比较好。
简要的意思就是在未来的2周之内可能发生地震。
http://www.discovervancouver.com/gvb/big-one.asp
Waiting for the Big One
No one can predict when it will hit or where or how strong it will be. But the experts are certain of one thing: it will hit. Southwestern British Columbia is overdue for a big, perhaps an enormous earthquake. Although it has been 50 years since the region had a close encounter of the shaky kind--a strong 7.3 Richter-scale quake north of Courtenay in 1946--the fact is that Vancouver sits atop the most active earthquake zone in Canada and the half-century hiatus since the Vancouver Island quake means subterranean pressures are building up again.
Each year, in fact, 300 quakes occur in the region, most small and unnoticed. But, according to researchers, once every 20 to 50 years a major jolt normally releases this stored pressure, collapsing chimneys, cracking walls, emptying shelves and producing minor landslips as happened in the Courtenay case. And once every 300 to 600 years, this region has been hit by a megathrust quake (8.5+) accompanied by 10- to 20-metre movements along the faultline, landslides and tsunamis on the coast. Were such an earthquake to happen today under Greater Vancouver, the results would be catastrophic. A recent study based on this scenario predicts 10 to 30 per cent of the area's homes would be damaged, 60 to 100 per cent of the older, unreinforced masonry buildings would suffer some degree of collapse, 15 per cent of the highrises would be rendered uninhabitable, many of the bridges and schools would be severely damaged, and thousands would die. It would be the largest natural disaster in Canadian history.
The origin of this danger lies in the Cascadia Subduction Zone, a 1,400 kilometre-long faultline that runs southward from Alaska along the west coast of the Queen Charlotte Islands and Vancouver Island to Oregon. Along this line, three different tectonic plates--the North American Plate, the Pacific Plate and the smaller Juan de Fuca Plate--join together like pieces in a gargantuan puzzle. But the situation is not static. The Pacific Ocean's bottom, spreading eastward at 4.3 centimetres a year (the speed that fingernails grow) is sliding beneath--or subducting-- under the westward-drifting continent of North America. Research in the past 20 years has found evidence that this motion is currently stuck. When it is released somewhere along the subducting zone--either offshore like the 1949 quake near the northern tip of the Queen Charlotte Islands that registered 8.0 or inland like the 1872 quake beneath Abbotsford that registered 7.5--the potential for disaster is considerable. A subduction quake off Mexico's coast in 1985 killed 9,000 people, most of them beneath collapsed buildings in Mexico City, 300 kilometres from the epicentre.
There are two scenarios for Greater Vancouver, says the National Earthquake Support Plan (NESP), a study into the region's earthquake preparedness. The first is the most likely: a moderately strong 6 to 7 Richter-scale quake, similar to the ones that hit San Francisco and Los Angeles in the past decade. This would produce significant damage and deaths in Vancouver. Since the 1989 San Francisco quake, a lot of engineering work has been done to upgrade local bridges and dams against seismic hazards. But little has been done about the vulnerability of older, masonry-walled schools, hospital buildings and brick structures like those in Gastown and Yaletown. Some could collapse. Even in a moderate quake, soil liquefaction would likely break the dykes along the Fraser River and the Georgia Strait foreshore, producing widespread flooding. Similar soil liquefaction would also likely affect many structures on reclaimed lands, especially those built on the periphery of False Creek, the Arbutus lowlands, the riverbanks of the Fraser, Sea Island and the Burrard Inlet waterfront all the way to Port Moody. Landslides and underwater slumpages would drop shoreline houses and port facilities. Power, gas and water systems could be affected for days.
The second--and less likely--NESP scenario, based on an 8.5 subduction quake in the Lower Mainland, would produce severe destruction within 100 kilometres of the epicentre. Many buildings would fail. Liquefaction would likely damage the airport, the Fraser Valley dykes, the Massey Tunnel and those bridge supports sunk into loose valley soils. Western sections of the Fraser Valley would flood. Up to 45 per cent of Vancouver's schools would suffer moderate to total collapse. Tsunamis and underwater slumpage would damage shoreline facilities, producing almost inevitable chemical spills, fires and mass evacuations. The death toll would be in the thousands.
The chance of such a catastrophe hitting Vancouver, though real, is extremely remote. Most historic, massive quakes have occurred along the subduction zone west of Vancouver Island and the Queen Charlotte Islands. The last significant quake to jolt Greater Vancouver struck in 1976, a 5.3 Richter-scale fracture 70 kilometres below Pender Island, It knocked people from their beds in White Rock, cut electrical services in Richmond, South Vancouver and the Sechelt Peninsula, and sent residents of West End highrises screaming into the halls as the building swayed for 30 seconds. The bigger 1946 Courtenay quake, much farther distant, dropped some Vancouver chimneys and cornices, emptied some local shelves, swayed buildings and bridges, and frightened everyone. Other occasional quakes over the past century near Vancouver have produced similar effects: no deaths, little damage and a lot of excitement. The fact is that--unlike California where the faults intersect the earth's surface--the plunging Cascadia Subduction Zone heads deeply under Vancouver so that any ruptures there, like the moderate Pender Island quake, lose some of their impact as the vibrations move upward toward the surface. It is the big 1872 Abbotsford quake that makes seismologists, structural engineers and emergency planners worry. Since few lived in the Fraser Valley at the time, its effect was minimal. But reports from that time say that waves a metre high rolled across the solid land and people were thrown to the ground by the force of the shaking. A repeat of that quake today would be a disaster.
The thought of a major historic quake under the Fraser Valley and the recent quakes on North America's west coast have propelled a series of government initiatives in British Columbia. A new emergency response plan now links a dozen different teams of experts--the heavy rescue group, damage assessment engineers, firefighters, communications experts, hazardous materials specialists, the coroner, counselling psychologists--into a network prepared to act quickly in the face of a calamity.
At the preventative level a large number of seismic-upgrading projects in the Vancouver region are either completed or under way. The Cleveland Dam in North Vancouver was brought to the highest seismic code in 1992. The 28 municipal bridges within Vancouver have now all been retrofitted against earthquakes. So have both the Oak Street and the Second Narrows bridges. (The Lions Gate Bridge remains vulnerable and unrepaired since its future is currently uncertain.) The Vancouver School Board is in the early stages of a massive upgrading of the 100 older school buildings at risk--one-third the total in the school system. With most of the unreinforced, brick school buildings in the region under its jurisdiction, Vancouver faces a retrofit bill of $300 million. Vancouver's two major hospitals, both originally housed in fragile, older buildings, are currently moving many of their departments into modern structures. A new $10 million, seismically safe Emergency Operations Centre for Vancouver and adjacent communities is being designed. It will act as the fulcrum of all disaster relief efforts. A new system of three saltwater pumping stations and earthquake-resistant piping is under construction at the periphery of the Vancouver downtown core. This will serve as a back-up in case, as happened in Japan in 1995, water mains break and widespread fires erupt. Corporations, especially those involved with transportation and hazardous materials, have spent millions more to secure their facilities. But the reality is that when it hits, a major earthquake in the Greater Vancouver area would be a disaster. Most wood-framed homes would ride out the shaking with little serious risk to their occupants. Modern structures, including all highrises and office towers, would remain standing. The old and vulnerable water system would inevitably fail. Gas mains would break and fires would follow. Sections of bridges, port facilities and old masonry-walled buildings would collapse. Train lines, roads and electrical distribution systems would fail. Loose objects within offices, factories and homes would be hurled around. Cornices and chimneys would fall. Glass would fly. Many people would die. Earthquakes search out the most vulnerable sections of a structure. And the Vancouver area has many older buildings that have never been tested in a great quake. The longer the shaking lasts, the worse it will be--as small initial structural failures grow exponentially as the vibrations continue. Someday this will happen here. Nothing can protect Vancouver from things that go bump in the night.
鉴于消息比较敏感，避免造成恐慌，我还是直接引用原文比较好。
简要的意思就是在未来的2周之内可能发生地震。
http://www.discovervancouver.com/gvb/big-one.asp
Waiting for the Big One
No one can predict when it will hit or where or how strong it will be. But the experts are certain of one thing: it will hit. Southwestern British Columbia is overdue for a big, perhaps an enormous earthquake. Although it has been 50 years since the region had a close encounter of the shaky kind--a strong 7.3 Richter-scale quake north of Courtenay in 1946--the fact is that Vancouver sits atop the most active earthquake zone in Canada and the half-century hiatus since the Vancouver Island quake means subterranean pressures are building up again.
Each year, in fact, 300 quakes occur in the region, most small and unnoticed. But, according to researchers, once every 20 to 50 years a major jolt normally releases this stored pressure, collapsing chimneys, cracking walls, emptying shelves and producing minor landslips as happened in the Courtenay case. And once every 300 to 600 years, this region has been hit by a megathrust quake (8.5+) accompanied by 10- to 20-metre movements along the faultline, landslides and tsunamis on the coast. Were such an earthquake to happen today under Greater Vancouver, the results would be catastrophic. A recent study based on this scenario predicts 10 to 30 per cent of the area's homes would be damaged, 60 to 100 per cent of the older, unreinforced masonry buildings would suffer some degree of collapse, 15 per cent of the highrises would be rendered uninhabitable, many of the bridges and schools would be severely damaged, and thousands would die. It would be the largest natural disaster in Canadian history.
The origin of this danger lies in the Cascadia Subduction Zone, a 1,400 kilometre-long faultline that runs southward from Alaska along the west coast of the Queen Charlotte Islands and Vancouver Island to Oregon. Along this line, three different tectonic plates--the North American Plate, the Pacific Plate and the smaller Juan de Fuca Plate--join together like pieces in a gargantuan puzzle. But the situation is not static. The Pacific Ocean's bottom, spreading eastward at 4.3 centimetres a year (the speed that fingernails grow) is sliding beneath--or subducting-- under the westward-drifting continent of North America. Research in the past 20 years has found evidence that this motion is currently stuck. When it is released somewhere along the subducting zone--either offshore like the 1949 quake near the northern tip of the Queen Charlotte Islands that registered 8.0 or inland like the 1872 quake beneath Abbotsford that registered 7.5--the potential for disaster is considerable. A subduction quake off Mexico's coast in 1985 killed 9,000 people, most of them beneath collapsed buildings in Mexico City, 300 kilometres from the epicentre.
There are two scenarios for Greater Vancouver, says the National Earthquake Support Plan (NESP), a study into the region's earthquake preparedness. The first is the most likely: a moderately strong 6 to 7 Richter-scale quake, similar to the ones that hit San Francisco and Los Angeles in the past decade. This would produce significant damage and deaths in Vancouver. Since the 1989 San Francisco quake, a lot of engineering work has been done to upgrade local bridges and dams against seismic hazards. But little has been done about the vulnerability of older, masonry-walled schools, hospital buildings and brick structures like those in Gastown and Yaletown. Some could collapse. Even in a moderate quake, soil liquefaction would likely break the dykes along the Fraser River and the Georgia Strait foreshore, producing widespread flooding. Similar soil liquefaction would also likely affect many structures on reclaimed lands, especially those built on the periphery of False Creek, the Arbutus lowlands, the riverbanks of the Fraser, Sea Island and the Burrard Inlet waterfront all the way to Port Moody. Landslides and underwater slumpages would drop shoreline houses and port facilities. Power, gas and water systems could be affected for days.
The second--and less likely--NESP scenario, based on an 8.5 subduction quake in the Lower Mainland, would produce severe destruction within 100 kilometres of the epicentre. Many buildings would fail. Liquefaction would likely damage the airport, the Fraser Valley dykes, the Massey Tunnel and those bridge supports sunk into loose valley soils. Western sections of the Fraser Valley would flood. Up to 45 per cent of Vancouver's schools would suffer moderate to total collapse. Tsunamis and underwater slumpage would damage shoreline facilities, producing almost inevitable chemical spills, fires and mass evacuations. The death toll would be in the thousands.
The chance of such a catastrophe hitting Vancouver, though real, is extremely remote. Most historic, massive quakes have occurred along the subduction zone west of Vancouver Island and the Queen Charlotte Islands. The last significant quake to jolt Greater Vancouver struck in 1976, a 5.3 Richter-scale fracture 70 kilometres below Pender Island, It knocked people from their beds in White Rock, cut electrical services in Richmond, South Vancouver and the Sechelt Peninsula, and sent residents of West End highrises screaming into the halls as the building swayed for 30 seconds. The bigger 1946 Courtenay quake, much farther distant, dropped some Vancouver chimneys and cornices, emptied some local shelves, swayed buildings and bridges, and frightened everyone. Other occasional quakes over the past century near Vancouver have produced similar effects: no deaths, little damage and a lot of excitement. The fact is that--unlike California where the faults intersect the earth's surface--the plunging Cascadia Subduction Zone heads deeply under Vancouver so that any ruptures there, like the moderate Pender Island quake, lose some of their impact as the vibrations move upward toward the surface. It is the big 1872 Abbotsford quake that makes seismologists, structural engineers and emergency planners worry. Since few lived in the Fraser Valley at the time, its effect was minimal. But reports from that time say that waves a metre high rolled across the solid land and people were thrown to the ground by the force of the shaking. A repeat of that quake today would be a disaster.
The thought of a major historic quake under the Fraser Valley and the recent quakes on North America's west coast have propelled a series of government initiatives in British Columbia. A new emergency response plan now links a dozen different teams of experts--the heavy rescue group, damage assessment engineers, firefighters, communications experts, hazardous materials specialists, the coroner, counselling psychologists--into a network prepared to act quickly in the face of a calamity.
At the preventative level a large number of seismic-upgrading projects in the Vancouver region are either completed or under way. The Cleveland Dam in North Vancouver was brought to the highest seismic code in 1992. The 28 municipal bridges within Vancouver have now all been retrofitted against earthquakes. So have both the Oak Street and the Second Narrows bridges. (The Lions Gate Bridge remains vulnerable and unrepaired since its future is currently uncertain.) The Vancouver School Board is in the early stages of a massive upgrading of the 100 older school buildings at risk--one-third the total in the school system. With most of the unreinforced, brick school buildings in the region under its jurisdiction, Vancouver faces a retrofit bill of $300 million. Vancouver's two major hospitals, both originally housed in fragile, older buildings, are currently moving many of their departments into modern structures. A new $10 million, seismically safe Emergency Operations Centre for Vancouver and adjacent communities is being designed. It will act as the fulcrum of all disaster relief efforts. A new system of three saltwater pumping stations and earthquake-resistant piping is under construction at the periphery of the Vancouver downtown core. This will serve as a back-up in case, as happened in Japan in 1995, water mains break and widespread fires erupt. Corporations, especially those involved with transportation and hazardous materials, have spent millions more to secure their facilities. But the reality is that when it hits, a major earthquake in the Greater Vancouver area would be a disaster. Most wood-framed homes would ride out the shaking with little serious risk to their occupants. Modern structures, including all highrises and office towers, would remain standing. The old and vulnerable water system would inevitably fail. Gas mains would break and fires would follow. Sections of bridges, port facilities and old masonry-walled buildings would collapse. Train lines, roads and electrical distribution systems would fail. Loose objects within offices, factories and homes would be hurled around. Cornices and chimneys would fall. Glass would fly. Many people would die. Earthquakes search out the most vulnerable sections of a structure. And the Vancouver area has many older buildings that have never been tested in a great quake. The longer the shaking lasts, the worse it will be--as small initial structural failures grow exponentially as the vibrations continue. Someday this will happen here. Nothing can protect Vancouver from things that go bump in the night.
，撑死砸瘫了，政府全管了
。阿门
。
