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AN earthquake with potential to cause significant loss of life and damage may be on its way.
University of Melbourne Earth scientist Prof Mike Sandiford said it was only a matter of time before a major quake struck.
He was unable to predict when or where the quake would hit.
But if it happened under a populated area it could be "catastrophic", he said.
It is feared the next big quake could reach up to 6.0 on the Richter scale.
Prof Sandiford said there were four major geological fault lines in populated Victorian areas, including the Selwyn Fault under Melbourne's southeastern suburbs.
"We can expect to see quakes up to magnitude 4 - such as the recent ones we've experienced - every two years," Prof Sandiford said. "Magnitude 5 quakes can be expected every 20 years.
"And the big ones - that can cause damage and loss of life at magnitude 6 or 7 - we should expect every 200 years. We haven't had one of those since the time of European settlement, so you could say it is due.
"If it occurs in a remote area with few people and little infrastructure, such as the Mallee, it would probably do little damage.
"But if it occurs under a city at a shallow level, it would be a disaster."
Prof Sandiford said a magnitude 5.6 quake in Newcastle in 1989 killed 13 people and caused $4 billion damage.
He said it would cost trillions of dollars to completely earthquake-proof Melbourne.
Seismologist Barry Hull said a magnitude 7 quake with an epicentre within a 50km radius of Melbourne's CBD would cause extensive structural damage, particularly to older buildings up to four storeys.
"Anything relatively modern, such as the Eureka Tower, would probably have been designed to withstand earthquakes," he said.
At 4.28pm on Wednesday, a 4.5 magnitude earthquake was felt in Melbourne and eastern Victoria, 12 days after a similar tremor.
Geological studies conducted by Prof Sandiford and colleagues have revealed intense underground seismic activity from Adelaide to southeast Victoria.
He said evidence of tectonic activity included the reshaping of mountains in the Otway and Dandenong ranges, the Mornington Peninsula and Mt Lofty Ranges near Adelaide.
Earthquakes had raised the Otways by 250m in the past three million years,while the Selwyn Fault, from Mt Martha to the Dandenong Ranges, had produced about 6m of uplift in the past 100,000 years.
"This is potentially six big earthquakes," Prof Sandiford said |
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参加活动-蝈蝈厨房之豆腐（5）国家宝藏&珍珠翡翠白玉汤 (2010-8-23) t_guoguo 
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