Saturday, August 28, 2010

Three killed, 40 injured in Iran quake

Posted: 28 August 2010 1250 hrs

TEHRAN - Three people, including two children, have been killed and 40 others injured in an earthquake which struck Iran's biggest desert, Dasht-e Kavir, state television reported on Saturday.

The 5.9 magnitude quake struck on Friday south of the northern city of Damghan.

In a separate report, the state television website quoted secretary general of Iran Red Crescent, Zaher Rostani, as saying that an elderly woman was also among those killed in the quake.

The website said six villages near Damghan were damaged in the quake which was about 278 kilometres (167 miles) east of Tehran.

The tremor, which struck at 11:53 pm (1923 GMT) Friday, was also felt in the capital Tehran.

Iran sits astride several major fault lines in the Earth's crust, and is prone to frequent earthquakes, many of which have been devastating.

The worst in recent times was a 6.3 magnitude quake which hit the southern city of Bam in December 2003, killing 31,000 people, about a quarter of its population, and destroying the city's ancient mud-built citadel.

- AFP /ls

Sunday, August 22, 2010

Moderate earthquake in sea off Greece

Posted: 22 August 2010 2157 hrs

ATHENS : A moderate earthquake of 5.4 magnitude hit an area in the Ionian Sea off the coast of Greece on Sunday without causing casualties or major damage, Greek and US authorities reported.

The epicentre of the tremor, which occurred at 1023 GMT, was located near the island of Zante, 329 kilometres (203 miles) west of Athens, seismologists at the Athens observatory said.

The quake was felt most strongly on Zante, local police said.

The US Geological Survey rated the magnitude as 5.6.

Greece is the European nation most exposed to earthquakes, experiencing about half of all those recorded on the continent. - AFP/ms

5.6-magnitude quake strikes off Mariana Islands

Posted: 22 August 2010 1847 hrs

SAIPAN, Northern Mariana Islands : An earthquake with a magnitude of 5.6 hit the Mariana Islands region on Sunday, a week after a 7.2 tremor and a series of strong aftershocks, US geologists said.

The latest quake struck at 7:33pm (0933 GMT) at a depth of 49 kilometres (30 miles) and was centred 505 kilometres from the Northern Marianas capital Saipan, the US Geological Survey said.

There have been more than 10 quakes of magnitude 5.0 or stronger since the powerful quake on August 14, but all were in a remote area of the Pacific Ocean and well away from populated areas.

The Hawaii-based Pacific Tsunami Warning Center said there was no indication of any widespread tsunami threat. - AFP/ms

Thursday, August 19, 2010

Rare double quake blamed for South Pacific tsunami

By ALICIA CHANG, AP Science Writer– Wed Aug 18, 11:05 am ET

LOS ANGELES – The deadly tsunami that pounded several South Pacific islands last year was spawned by not one but two monstrous earthquakes, surprising new research reveals.

Initially, it was thought that a single powerful magnitude-8.1 jolt triggered the tsunami last September 29 that killed nearly 200 people in Samoa, American Samoa and Tonga.

Two teams using different research techniques have now separately concluded that the disaster was the result of a rare double whammy — two so-called great earthquakes with magnitudes greater than 8 — that hit within minutes of each other.

What's notable, they say, was that the quakes occurred along separate fault lines and ruptured differently.

Although the researchers differed on which struck first, their discovery of a one-two seismic punch solves a mystery that has baffled scientists since the disaster.

The findings are published in Thursday's issue of the journal Nature.

When the South Pacific sea floor rumbled last year, scientists initially blamed it on a "outer rise" earthquake of magnitude-8.1 caused by the flexing and bending of the Pacific tectonic plate. But tsunami waves did not arrive at the predicted times and the aftershocks did not cluster around the main quake — as they normally would — suggesting that something more complicated was at play.

Using GPS data and deep-ocean tsunami wave observations, a group led by geophysicist John Beavan of the New Zealand geological agency GNS Science determined that the tsunami was actually generated by two powerful quakes — the magnitude-8.1 "outer rise" quake and a magnitude-8 "megathrust" jolt caused by the diving of one plate under another.

While Beavan's group is not sure which hit first, a separate team led by Thorne Lay of the University of California, Santa Cruz, concluded the magnitude-8.1 quake unleashed the megathrust jolt. Normally, megathrust quakes trigger other jolts. Ground vibrations from the first were so strong that they masked the energy released by the second quake.

The second tremor "does show up clearly on seismic records, but only once you look very hard," Lay said.

Scientists not involved in the latest research said the findings shed light on what happened in the South Pacific, but more work is needed.

"It is difficult to say how typical this behavior is in the region," said U.S. Geological Survey geophysicist Paul Earle. That's because there's a long time between earthquakes and modern instruments weren't available for previous massive earthquakes, he said.


Thursday, August 12, 2010

Strong earthquake rattles Ecuador and Peru

Posted: 12 August 2010 2236 hrs

WASHINGTON: A strong 7.1-magnitude earthquake rocked Ecuador and parts of Peru on Thursday, but its epicentre was deep underground in a remote Amazonian region and only one injury and light damage was reported.

The quake, which experts from the US Geological Survey said hit at 6:54 am (1154 GMT), 175 kilometres southeast of Quito, lasted for about 40 seconds and was felt around the country and in neighbouring Peru.

One person in a southwestern fishing port was injured by a crumbling wall, Ecuador Red Cross spokesman Jorge Arteaga told AFP.

"So far that is the only victim," he said, adding that a handful of buildings including a firehouse had their walls crumble as a result of the quake.

The epicenter of the quake was deep, some 210 kilometres under the Amazonian jungle, which Ecuadoran officials said was the reason for the lack of damage above ground. No tsunami was generated.

The USGS said the nearest urban centre was some 145 kilometres to the west - Ambato - an Ecuadoran city high in the Andes mountains which is home to a volcano of the same name and suffered a devastating quake back in 1949.

The Geophysical Institute of Peru said Thursday's quake was also felt by Peruvians along the border in the Amazonian jungle regions.

Sandro Vaca, an expert from the Geophysical Institute of Ecuador, said no aftershocks had been detected during the morning.

The USGS revised its estimate of the quake's magnitude several times, from 6.9 to 7.2 and then back to a 6.9 before finally settling on 7.1.

Ecuadoran experts first put the quake at 6.9 on the Richter scale before revising the magnitude upwards to 7.2.

The USGS uses the moment magnitude scale, which measures the amount of movement on the underground fault and the area of the fault that ruptured.

Many seismologists now use that system rather than the Richter scale, which measures the size based upon the amount of ground shaking.

According to the USGS, the quake was the largest involving Ecuador since a 7.2-magnitude temblor off the coast in 1998. Ecuador's deadliest was the 6.8-magnitude quake in 1949 in Ambato which killed more than 5,000 people.

The Ecuadoran Andes are part of the Pacific Ring of fire, where most of history's deadliest quakes, tremors and volcanic explosions have occurred.

The weak line in the Earth's crust stretches along the western coast of the Americas and through the island nations of the South Pacific and on through Southeast Asia.

- AFP/ls/de

Tuesday, August 10, 2010

Moderate quake hits northern Japan

Posted: 10 August 2010 1516 hrs

TOKYO: A 5.8-magnitude earthquake hit northern Japan Tuesday, but there was no tsunami warning and no immediate reports of damage, US and Japanese seismologists said.

The underwater quake occurred at 2:50 pm (0550 GMT) off Iwate prefecture in the Pacific, 515km (320 miles) north of Tokyo, according to the US Geological Survey.

Its depth was estimated at 21km, the USGS said.

No tsunami warning was issued by the Japan Meteorological Agency.

Around 20 per cent of the world's most powerful earthquakes strike Japan, which has developed one of the most sophisticated tsunami warning systems.


Major 7.5 earthquake, tsunami hit Pacific's Vanuatu

Posted: 10 August 2010 1505 hrs

SYDNEY: A major 7.5-magnitude earthquake hit the Pacific island nation of Vanuatu on Tuesday, generating a small tsunami and sending thousands of frightened people running for the hills.

The undersea quake, 35km deep and just 40km from the capital Port Vila, shook buildings in the city for about 15 seconds, but did not appear to have caused significant damage.

Foreign hotel guests and some residents raced to higher ground in case of a possible tsunami, locals said, while police sounded sirens to warn people to evacuate.

"We don't have any damage. But we have evacuated our guests to the top of the hill just to be safe, although we have not received any tsunami warning yet," hotel employee Rowan Lulu told AFP.

"A lot of people are evacuating to higher ground in the city as a precaution but as far as I know there is no major damage in Vila, just things falling off shelves," he said.

"We felt it very strongly," another hotel employee said.

Witnesses said people working in the capital's tallest buildings were also evacuated, while the powerful quake was felt in the archipelago's other islands further north.

"People were moving to higher ground," resident Steve Ayong-Nirua told AFP.

"There was a call on the radio calling on drivers to drive slowly in case of aftershocks," he added.

The Pacific Tsunami Warning Centre said a 23cm (9.2 inch) tsunami hit Port Vila, but warned bigger waves may be seen in other areas.

"Higher wave amplitudes may yet be observed along coasts near the earthquake epicentre," the Centre said.

Vanuatu, which lies between Fiji and Australia and north of New Zealand, is in the "Pacific Ring of Fire" known for its high seismic and volcanic activity caused by friction between moving plates in the Earth's crust.

In May, a 7.2 earthquake prompted a brief tsunami alert, and at least three earthquakes measuring 6.0 or stronger have hit the archipelago since the start of July.

The country was hit by three major quakes last October, while a giant plume of volcanic ash disrupted domestic flights in neighbouring New Caledonia in recent months.

The US Geological Survey measured the latest earthquake at 7.5 while Geoscience Australia said it was 7.6 and at a depth of 60km.

The Pacific centre said it did not cause a widespread tsunami, while scientists in New Zealand believed the country was not under threat from any destructive waves.


Friday, August 6, 2010

5.6-magnitude quake strikes Indonesia

Posted: 06 August 2010 1734hrs

JAKARTA : A moderate 5.6-magnitude earthquake struck the Indonesian province of Maluku on Friday, the local Meteorological and Geophysics agency said, but no tsunami warning was issued.

The quake struck at 3:58 pm (0858 GMT), 317 kilometres (196 miles) northwest of Saumlaki at a depth of 10 kilometres, according to the agency.

Indonesia sits on the Pacific "ring of fire", where the meeting of continental plates causes high volcanic and seismic activity. - AFP/ms