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Tuesday, December 28, 2010

How to examine earthquakes??


Without warning the ground begins to shake. Buildings topple, crushing or burying those inside; gas and water mains fracture and erupt; the telephone system, overwhelmed by panicked calls, collapses. Down in the park on the shore of the Sea of Marmara people taking a stroll in the spring air have but a moment to register the tsunami about to overwhelm them. By the end of the day 35,000 people are dead and 200,000 injured, and some 80,000 buildings lie in ruins. Others, like the great Blue Mosque, survive but with marks that will serve as a reminder for decades to come of the great earthquake of 2017 - the one everyone knew was coming but did little to prepare for.
It may never be like this - it may never happen - or it could be worse. Man may have sent probes to the furthest reaches of the Solar System and gazed towards the edge of the visible universe but he is still woefully ill-informed about the caprices of his own planet. Some of the most ill-informed people are in most danger, those whose homes straddle the faultlines, fractures in the earth’s crust caused by the grinding of tectonic plates. Like the North Anatolian Fault, at its nearest 10 miles from Istanbul.

The attitude of people living alongside these fissures varies greatly, from fear to fatalism to simple ignorance of their presence. It was with this in mind that Tamsin Davies and her sister Serena, together with their friend Adam Whitaker, decided to explore the faultlines of Europe, from Iceland to Italy and Greece, and then eastwards into Turkey. The Faultine Living Expedition is backed jointly by the Royal Geographical Society and Land Rover. Each year the bodies choose one proposal for an expedition to a remote corner of the world to examine societies that live, literally and fuguratively, on the edge. Landrover provides the expedition vehicle and £10,000 under its Go Beyond The Everyday sponsorship scheme.
"If you look at a faultline map there are hundreds of them, and any one can produce an earthquake,” says Serena, a documentary maker. “And we don’t know enough about them. A headline we read the other day summed it up: ‘Scientists can’t predict earthquakes but toads might be able to’.”
The Daily Telegraph caught up with the expedition in Izmit, a town to the east of Istanbul devastated by an earthquake in August 1999. Some 18,000 people died in that quake, a product of the same fault that may one day spell disaster for Istanbul. Serif Baris, a professor of geophysics who keeps an eye on the North Anatolian Fault, explains: “In 1999, after the earthquake, it was predicted that the chance of another, measuring 7.5 on the Richter Scale, hitting Istanbul within 30 years was 65 per cent. And now ten years have gone by.”
The casualty figures quoted in the scenario for 2017, along with the number of buildings destroyed, are those expected by Professor Baris.
“Most people know the risk but when you ask if they are prepared less than 20 per cent would say they are ready. In Japan they train their children for earthquakes in kindergarten. In Turkey there is often a kind of fatalism. Some people think buildings are so badly built that they will collapse and they will die anyway, so why bother with training drills.”
The reactions of earthquake survivors vary greatly, from relief at one’s survival to guilt for not helping others, and fear that it will happen again.
The team interviewed one man caught in the 1999 quake who could not get over the fact that in his rush to escape what appeared to be his toppling home he had abandoned his wife and children. Then there was Mehmet Koc, a 36 year-old belt maker. He lived in Avcilar, one of the districts of Istanbul hit by the 1999 quake.
“I was unable to sleep for 2 years after that day,” he said. “I couldn’t have a proper sleep for that time.
“I go on, I survive. I’m afraid of the second one – not now as afraid as I was. I would say it is a normal fear.”
Nuran Altiparmak, 45, a shop assistant from Istanbul, lost her hair, so great was her trauma.
“It ruined my psychology,” she said. “Still I receive psychological treatment. The nerves in my legs are damaged. My husband lost his job and we lost money. We almost divorced because of the stress. So many things - not only psychological.
“My heart beats so fast when I think about a second earthquake because there are so many wounds. I don’t’ know how to put it into words.”
The expedition began in Iceland, a dynamic landscape sculpted by earthquakes and volcanic eruptions, the legacy of its position astride the fault separating the Eurasian and North American tectonic plates. There are benefits to faultline status. A quarter of that country’s total power needs are provided by geothermal energy, and 87 per cent of its domestic heating.
Iceland, though, is a sparsely-populated place. In Italy the team saw how a once prosperous, densely-populated area can be laid low for years by movements in faults that have remained ignored for centuries.
Last year, the town of L’Aquila in central Italy was hit by a 6.3 earthquake which killed 308 people, injured some 1,500 and left 65,000 people homeless. The town, built on an old lake bed which amplifies seismic waves, was last struck by an earthquake in 1706, three years after a more powerful quake killed some 5,000 people. Despite its history, there was general ignorance in the town of the dangers.
“People in these zones often fail to understand the risks,” says Serena. “There is a barrier between them and the information they need. There is the attitude that, ‘We had our earthquake a hundred years ago so we’re fine now. Among the older generation, particularly, there is also a fatalistic approach.”
The centre of L’Aquila is still a no-go area.
“It is a beautiful medieval centre that is completely dead,” says Adam. “The buildings have not collapsed but they are uninhabitable because no-one knows how unsafe they are.”
L’Aquila is where the toads come in. Days before the quake struck, zoologists studying a colony of toads some 50 miles from the epicenter observed that 96 per cent of the males suddenly got up and left. Human predictive skills are some way off. The devastating earthquake in Haiti in January of this year has been attributed to a previously undiscovered fault.
Even here, in seismically sleepy Britain, we should not be too complacent. The British Geological Survey warned recently that the earthquake threat to London is greater than generally appreciated. Not the devastating quakes of abroad but tremors capable of inflicting real damage and some deaths.
A quake of Magnitude 5 or above occurs every century or so in Britain. In April 1580, a tremor centred on the Dover Strait damaged a large number of buildings in London and killed two people.
“The same earthquake happening tomorrow will impact far more people than was the case in the 16th Century,” explained Roger Musson of the BGS. “The size of London in terms of population is about 50 times more today. So if two people were killed in London in 1580, you can imagine for yourself what sort of scaling up that could mean for a contemporary earthquake of the same size.”
The threat to Tehran, the expedition’s next destination, is rather more pressing – about the same as that facing Istanbul. There is talk there of one day moving the capital to a less dangerous location.
On the whole, though, humanity tends to adopt a fatalistic attitude to the occasionally lethal temper tantrums of its home planet.
Interviewed by the Faultine team, Soffia Sigurdardottir, a member of the search and rescue team in the town of Selfoss, southern Iceland, explained: “This is normal life. You make these precautions, and when a strong earthquake comes you wait for 10 seconds; and if you’re still alive, you’re still alive.”

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