Japan Earthquake - 5-26-2003

JAPAN EARTHQUAKE

5-26-2003

104 people injured - no deaths

By Elaine Lies

SENDAI, Japan (Reuters) - Aftershocks rattled northeastern Japan on Tuesday, a day after a powerful earthquake, but officials said it was not the huge quake which experts say is due to hit the region within a few years.

The government said 104 people were injured but no deaths resulted from the earthquake, which struck early Monday evening and measured 7.0 on the Richter scale, rocking buildings as far away as Tokyo about 280 miles to the south.

"This was an extremely large-scale earthquake, but for its scale, the damage and injuries were quite small. That's something to be thankful for," said Shiro Asano, governor of Miyagi Prefecture, close to the center of the tremor.

Damage was limited and there was no tsunami, or giant wave, because the quake's focus, 12 miles off the east coast, was deep at 44 miles below the surface.

It hit a mostly agricultural area that has several large cities and some high-tech factories.

Asano said it was not the so-called Miyagi-oki earthquake, which has hit the region periodically in a cycle of around 30 to 40 years and last struck in 1978, killing 28 people.

"This earthquake is not the 'Miyagi-oki' quake that we are expecting," he said at a meeting of a prefectural task force set up to deal with the quake.

But the governor told officials to remain vigilant, pointing out that a tremor similar to the one on Monday served as a precursor to the big 1978 earthquake.

"Four months before the 1978 quake there was a fairly large quake, so we should take this one as a possible lesson. The Miyagi quake will definitely come some day," he added.

LESSONS FROM THE PAST

In terms of magnitude, Monday's earthquake was about the same as the devastating earthquake in the western Japanese city of Kobe eight years ago, which measured 7.2 on the Richter scale and left 6,430 dead.

Local disaster prevention officials said the limited damage from Monday's tremor was most likely due to stricter building codes introduced after the 1978 earthquake, while residents said the experience 25 years ago had made them better prepared.

"The one 25 years ago was much worse, because everything was out -- gas, electricity, water," said taxi driver Itaru Matsuoka, 63, adding that people this time were much quicker to turn off their gas.

"I know that's the first thing my wife does. She's terrified of fire."

Monday's earthquake, the largest to hit Japan in two years, shattered windows, buckled roads and produced cracks in buildings in Sendai, a city of around one million about 90 km (56 miles) south of the epicenter.

Over a thousand passengers were stranded in Sendai railway station after bullet train services were stopped. Ten families were evacuated from their homes for fear of landslides.

About 35,000 homes lost power supplies but electricity was restored for most within a few hours.

A highway in northeastern Japan was temporarily closed. Phone networks were snarled.

Regional utility Tohoku Electric Power Co Inc said an 825,000-kilowatt (kW) nuclear reactor, the Onagawa No.3 unit near Sendai automatically shut down due to the quake.

Japan's largest oil refiner, Nippon Oil Corp, said it had started shutting down its 145,000 barrels per day Sendai refinery, although its facilities appeared to be undamaged.

In Tokyo, buildings shook violently and lamps swayed, sending workers scurrying to doorways.

Japan sits atop a junction of at least three tectonic plates, the slabs on the earth's surface whose movements cause earthquakes. (Additional reporting by Masayuki Kitano)

Seventy-two injured as north-east Japan suffers major earthquake

JULIAN RYALL IN TOKYO

A MAJOR earthquake rocked most of northern Japan yesterday, rocking buildings and knocking out power lines, but despite being larger than last week’s Algerian tremor, there were no reports of any deaths.

The earthquake, measuring seven on the Richter scale, disrupted train services and flights across north-east Japan. Kyodo news agency said at least 72 people were injured, five of them seriously.

The earthquake, the largest to hit Japan in three years, shattered windows in the city of Sendai and knocked objects from shelves. It also damaged buildings, left cracks in roads, and caused some landslides. Japanese television showed two houses on fire and a blaze was reported at the Indian embassy in Tokyo, more than 180 miles to the south, but damage was otherwise relatively light in what is largely an agricultural region with few large cities.

Japan is one of the most earthquake-prone countries in the world - Tokyo sits on the junction of four active tectonic plates that frequently shift, causing tremors.

But Japan vividly remembers the "Great Hanshin Earthquake", which killed more than 6,400 people when it flattened the city of Kobe and surrounding areas in 1995. It has accordingly adopted tough building standards. Bullet train services to the north of Tokyo were briefly interrupted while tracks were checked and similar examinations were conducted on the runways at Tokyo’s Narita and Haneda airports, but the disruption was minimal, the operators said.

"I was surprised because it shook so strongly," a government official in Morioka city, about 300 miles north of Tokyo. "It shook strongly enough to make you want to hang on to something." The man was on the sixth floor of a building when the quake hit.

One man was admitted to hospital in Sendai with cuts sustained when a window shattered, while a woman was injured when a clock fell on her. Sendai is home to one million people and is the largest city in the region.

In Tokyo, buildings swayed and lights and blinds shook from side to side, causing members of the public to take shelter under tables.

Supermarket shelves were wiped clear by the power of the minute-long quake, which also disconnected electricity supplies to 35,000 homes. More than 70 lifts were halted automatically when the tremor struck.

The quake was centered 40 miles below the sea floor and about 12 miles off the coast of north-east Miyagi prefecture, the Meteorological Agency said. "The quake was felt over a very broad area," said Noritake Nishibe, a Central Meteorological Agency official.

He said it was the strongest quake in Japan in about two years, and that aftershocks were expected. He suggested that the impact of the quake might have been mitigated by its depth.

Another mitigating factor was apparently the fact that it was a swaying, side-to-side type of tremor, rather than the far more destructive up-and-down motion quakes. Kobe was essentially destroyed in less than 30 seconds eight years ago by an up-and-down type quake. The possibility of a major tsunami, or tidal wave, was also ruled out.

7.0 quake shakes Japan

SUSAN KIM

BALTIMORE (May 26, 2003) —

A 7.0-magnitude earthquake hit Japan Monday, the strongest to shake the main island in about two years.

The northeastern coast of Honshu was hardest hit, with the temblor causing at least 19 landslides and three fires in that region.

Houses were damaged in the northern states of Miyagi, Iwate, Akita and Aomori.

The quake, though strong, had a limited impact because it was so deep, Japanese government reports said.

It was centered 44 miles below the sea some 12 miles off the coast of northeastern Miyagi state.

A few dozen people were injured, with most of the injuries minor.

The quake was felt hundreds of miles away in Tokyo, where it rocked tall buildings.

Forecasters reported no danger of a tsunami, though more than 90 aftershocks were reported Monday.

In October 2000, a 7.3-magnitude quake hit the southwestern Tottori state. When a 7.2 quake struck the city of Kobe in 1995, more than 5,000 people died.

Posted May 26, 2003 10:25 PM

Earthquake different from predicted 'big one'

Yomiuri Shimbun

The geographic phenomenon responsible for the earthquake in the Tohoku region Monday was different from the phenomenon that a government committee has predicted will cause a major earthquake off Miyagi Prefecture in the near future, according to seismologists.

The government's Earthquake Research Committee has warned that there is a 98 percent chance that a strong earthquake will occur off Miyagi Prefecture in the next 30 years.

The Meteorological Agency said it was possible that Monday's quake may trigger the predicted major quake and called for vigilance.

The epicenter of the quake Monday was 71 kilometers under the sea 20 kilometers off Kesennuma.

As the Pacific tectonic plate under the ocean off Miyagi Prefecture is gradually sinking below the terrestrial plate, seismologists said the tremor likely occurred within the Pacific plate.

The Pacific plate forms a peak that is pushed upward as the bottom of the plate contracts.

In an attempt to return to its original shape, the plate contracts on top and expand underneath.

The agency said that Monday's quake likely was caused by a contraction deep within the upper side of the submerged part of the plate.

The government committee has predicted that a quake off Miyagi Prefecture would be centered about 40 kilometers underground and slightly southeast of the center of the quake that occurred Monday.

The committee predicts that the quake would be caused by movement at the plate boundary, where the Pacific and terrestrial plates meet. The terrestrial plate accumulates distortion while being pulled down by the tectonic movements. When the distortions become large enough, the plate rebounds upward in an attempt to correct them, causing an earthquake.

Major earthquakes of this type have occurred off Miyagi Prefecture about once every 40 years--in 1861, 1897, 1936 and 1978.

The 1978 quake measured 7.4 on the Richter scale. Twenty-eight people died in that quake and about 1,300 were injured.

As 25 years have passed since the previous plate boundary quake in 1978, the distortion in the plate has built up considerably, the seismologists said.

The Meteorological Agency warned that the quake on Monday may trigger a major plate boundary earthquake.

Noritake Nishide, chief of the agency's earthquakes and tsunami section, said, "We'll quickly calculate whether the balance of energy in the plate boundary has been changed by Monday's earthquake and by how much."

Related Web Sites:

Earthquake Information a list of recent global activity from the National Earthquake Center.

Worldwide Earthquake Locator provides a list of recent global and maps of the approximate location of the center of activity from the University of Edinburgh.

Earthquake Magnitude Comparisons is a chart that gives insight into the impacts of different strengths of earthquakes.

Central U.S. Earthquake History takes a detailed look at the history of quakes in the New Madrid Seismic Zone.

Recent Earthquakes provides information and maps of recent California and Nevada earthquakes.