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Posts Tagged ‘earthquake’

Strong 6.8 quake hits near East Timor

August 30, 2011 Comments off

afp

DILI, East Timor — A powerful 6.8-magnitude earthquake struck deep beneath the seabed near East Timor on Tuesday but no tsunami warning was issued, a local geophysics agency said.

The quake hit at 13:57 pm (0657 GMT) at a depth of 469 kilometres (291 miles), about 271 kilometres northeast of the capital, Dili, according to Indonesia’s geophysics agency.

“We did not issue a tsunami warning. There are no reports of damage so far,” said Novita, an official at Indonesia’s national quake centre.

“The quake was felt by the people in Timor island, but not strongly,” Read more…

Virginia quake may have exceeded nuclear plant design

August 30, 2011 Comments off

reuters

The historic earthquake that shut Dominion Resources Inc’s North Anna nuclear plant in Virginia last week may have shaken the facility more than it was designed to withstand, the U.S. nuclear regulator said on Monday.

The Nuclear Regulatory Commission said it had sent a special inspection team to the plant rocked by the 5.8-magnitude quake, after initial reviews from Dominion indicated the ground motion may have exceeded North Anna’s design parameters.

The plant cannot be restarted until the operator can show no Read more…

Papua New Guinea rattled by 6.8 quake

August 1, 2011 Comments off

afp

SYDNEY — The Pacific island nation of Papua New Guinea was jolted by a powerful 6.8-magnitude earthquake Monday, prompting a minor tsunami warning, but there were no immediate reports of damage or injuries.

The US Geological Survey said the quake occurred at a depth of 16 kilometres (10 miles), some 131 km (81 miles) east of Wewak and 706 kilometres north of the capital Port Moresby.

“No destructive widespread tsunami threat exists based on historical earthquake and tsunami data,” the Pacific Tsunami Warning Centre said.

“However, earthquakes of this size sometimes generate local tsunamis that can be destructive along coasts located within a hundred kilometers of the earthquake epicentre.

“Authorities in the region of the epicentre should be aware of this possibility and take appropriate action.”

GeoScience Australia measured the quake at 6.6 and said it would have been felt more than 800 kilometres (496 miles) away, but damage would only have been caused within a radius of 67 kilometres from the epicentre.

The PNG Geophysical Observatory said that residents of the coastal town of Wewak, home to about 18,000 people, would have been severely shaken, but early reports suggested no major damage or injuries.

“Preliminary reports we are receving indicate that no real life-threatening damage and it is not an event where a tsunami is thought to be Read more…

New Force Driving Earth’s Tectonic Plates: ‘Hot Spots’ Of Plume From Deep Earth Could Propel Plate Motions Around Globe Discover Scripps Researchers

July 7, 2011 1 comment

nanopatentsandinnovations

Bringing fresh insight into long-standing debates about how powerful geological forces shape the planet, from earthquake ruptures to mountain formations, scientists at Scripps Institution of Oceanography at UC San Diego have identified a new mechanism driving Earth’s massive tectonic plates.

Reconstruction of the Indo-Atlantic Ocean 63 million years ago, during the time of the superfast motion of India which Scripps scientists attribute to the force of the Reunion plume head. The arrows show the relative convergence rate of Africa (black arrows) and India (dark blue) relative to Eurasia before, during and after (from left to right) the period of maximum plume head force. The jagged red and brown lines northeast of India show two possible positions of the trench (the subduction zone) between India and Eurasia depending on whether the India-Eurasia collision occurred 52 million years ago or 43 million years ago.

Reconstruction of the Indo-Atlantic Ocean 63 million years ago, during the time of the superfast motion of India which Scripps scientists attribute to the force of the Reunion plume head.  The arrows show the relative convergence rate of Africa (black arrows) and India (dark blue) relative to Eurasia before, during and after (from left to right) the period of maximum plume head force. The jagged red and brown lines northeast of India show two possible positions of the trench (the subduction zone) between India and Eurasia depending on whether the India-Eurasia collision occurred 52 million years ago or 43 million years ago.

Credit: Scripps Institution of Oceanography

Scientists who study tectonic motions have known for decades that the ongoing “pull” and “push” movements of the plates are responsible for sculpting continental features around the planet. Volcanoes, for example, are generally located at areas where plates are moving apart or coming together. Scripps scientists Steve Cande and Dave Stegman have now discovered a new force that drives plate tectonics: Plumes of hot magma pushing up from Earth’s deep interior. Their research is published in the July 7 issue of the journal Nature.

Using analytical methods to track plate motions through Earth’s history, Cande and Stegman’s research provides Read more…

Volcano expert fears we’ll see a super eruption

June 2, 2011 1 comment

walesonline

Volcanologist Clive Oppenheimer yesterday warned there was a one-in-500 chance of the world being hit by a super- volcano this century.

The reader in vulcanology at Cambridge University told a Hay audience: “That might not sound like much, but it is a lot more likely than an asteroid impact.

“The events in Japan remind us that you can have a tsunami and earthquake and a nuclear plant there as well and you can have these chain reaction events that are actually quite calamitous and they are not unimaginable.”

Examining geological, historical and archeological records, the expert took the audience on a journey back to three volcanic eruptions that have shaken the world – the 1815 Tambora volcano in Indonesia that Read more…

Chile Earthquake Today – Terremoto Felt in Santiago

June 1, 2011 Comments off

lalate

Chile Earthquake Today, Terremoto, Felt in Santiago

CORAL GABLES (LALATE) – – Chile was struck by a 6.4 earthquake today. Chile’s earthquake or terremoto was felt in Santiago and struck during the morning rush hour. Today’s temblor is the latest powerful earthquake to strike the country this year. No reports of damage or injury today have been given.

Today’s earthquake activity in Chile produced the highest quake in the region in recent weeks. In April, Chile experienced two major earthquakes with hours of each other. On April 2, a moderate 5.1 quake struck forty-one miles south of San Antonio, Valparaiso. That temblor was followed hours later by an earthquake registering a 5.9 magnitude, centered eighty-three miles east of Iquique in the Tarapaca region stuck.

Like the April earthquakes, today’s temblor struck during the early morning Read more…

Oil spill, explosion hit crippled Japan nuclear plant

May 31, 2011 Comments off

klewtv

Oil spill, explosion hit crippled Japan nuclear plantInternational Atomic Energy Agency fact-finding team leader Mike Weightman inspects Reactor Unit 3 at the Fukushima Dai-ichi nuclear plant, May 27, 2011. (AP Photo/IAEA)

 

TOKYO (AP) – An oil spill and a small explosion have caused limited damage – but no further radiation leaks – at the crippled nuclear power plant in northeastern Japan, the plant operator said Tuesday.

Workers at Fukushima Dai-ichi plant found an oil spill in the sea near reactors five and six, which were in shutdown when the earthquake and tsunami struck March 11, Tokyo Electric Power Co. said. The spill was contained by an oil fence, TEPCO spokesman Taichi Okazaki said.

The explosion workers heard at reactor four was Read more…

Time to shift view of seismic risk – experts

May 25, 2011 Comments off

terradaily

Knowledge of seismic risk is badly skewed in favour of earthquakes that occur on plate boundaries, such as the March 11 temblor that hit northeast Japan, rather than those that strike deep inland, a pair of scientists said on Sunday.

In commentary appearing in the journal Nature Geoscience, Philip England of Oxford University and James Jackson of Cambridge University say that in seismic terms, the 9.0-magnitude Sendai quake was “a remarkable story of resilience.”

Good civic training and building construction meant that the death rate was “impressively low,” they said. Around 25,000 people died, or 0.4 percent of those exposed to the event, and most of these died from the tsunami that followed.

The March 11 event occurred on a plate boundary, where the jigsaw of plates that float on Earth’s crust jostle and grind and slide under each other.

England and Jackson say plate boundaries are relatively well-studied, but a far greater threat lurks in continental inland areas.

“Death rates in earthquakes within continental interiors have often exceeded five percent and can be as high as 30 percent,” they warn.

According to their count, over the past 120 years, there have been around Read more…

Atmosphere Above Japan Heated Rapidly Before M9 Earthquake

May 18, 2011 2 comments

Infrared emissions above the epicenter increased dramatically in the days before the devastating earthquake in Japan, say scientists.

Technology Review
Published by MIT

Geologists have long puzzled over anecdotal reports of strange atmospheric phenomena in the days before big earthquakes. But good data to back up these stories has been hard to come by.

In recent years, however, various teams have set up atmospheric monitoring stations in earthquake zones and a number of satellites are capable of sending back data about the state of the upper atmosphere and the ionosphere during an earthquake.

Last year, we looked at some fascinating data from the DEMETER spacecraft showing a significant increase in ultra-low frequency radio signals Read more…

Fukushima Reactor 1 melted down, 2 and 3 may have too

May 17, 2011 Comments off

arstechnica

Yesterday, TEPCO, the company responsible for running the Fukushima nuclear reactors, released a provisional analysis of the events that occurred in Unit 1, one of the reactors that was active when the tsunami struck. In five stark pages, the report lays out the impact of the tsunami on the facility: water levels that plunged below the bottom of the fuel, a complete meltdown of the nuclear fuel, and extensive damage to the reactor vessel.

The new analysis was enabled by the recent installation of air purifiers that let personnel reenter the reactor control room for the first time. Once inside, they were able to recalibrate some of the instruments that have been monitoring the reactor core; Read more…