Earthquake acoustics could warn of impending massive tsunami

Washington, June 7 (ANI): Stanford scientists have identified key acoustic characteristics of the 2011 Japan earthquake that indicated it would cause a large tsunami, and suggested that the technique could be applied worldwide to create an early warning system for massive tsunamis.

On March 11, 2011, a magnitude 9.0 undersea earthquake occurred 43 miles off the shore of Japan. The earthquake generated an unexpectedly massive tsunami that washed over eastern Japan roughly 30 minutes later, killing more than 15,800 people and injuring more than 6,100. More than 2,600 people are still unaccounted for.

Now, computer simulations by Stanford scientists reveal that sound waves in the ocean produced by the earthquake probably reached land tens of minutes before the tsunami. If correctly interpreted, they could have offered a warning that a large tsunami was on the way.

Because the sound from a seismic event will reach land well before the water itself, the researchers suggest that identifying the specific acoustic signature of tsunami-generating earthquakes could lead to a faster-acting warning system for massive tsunamis.

The earthquake's epicenter had been traced to the underwater Japan Trench, a subduction zone about 40 miles east of Tohoku, the northeastern region of Japan's larger island. Based on existing knowledge of earthquakes in this area, seismologists puzzled over why the earthquake rupture propagated from the underground fault all the way up to the seafloor, creating a massive upward thrust that resulted in the tsunami.

Direct observations of the fault were scarce, so Eric Dunham, an assistant professor of geophysics in the School of Earth Sciences, and Jeremy Kozdon, a postdoctoral researcher working with Dunham, began using the cluster of supercomputers at Stanford's Center for Computational Earth and Environmental Science (CEES) to simulate how the tremors moved through the crust and ocean.

The researchers built a high-resolution model that incorporated the known geologic features of the Japan Trench and used CEES simulations to identify possible earthquake rupture histories compatible with the available data.

Retroactively, the models accurately predicted the seafloor uplift seen in the earthquake, which is directly related to tsunami wave heights, and also simulated sound waves that propagated within the ocean.

In addition to valuable insight into the seismic events as they likely occurred during the 2011 earthquake, the researchers identified the specific fault conditions necessary for ruptures to reach the seafloor and create large tsunamis.

The model also generated acoustic data; an interesting revelation of the simulation was that tsunamigenic surface-breaking ruptures, like the 2011 earthquake, produce higher amplitude ocean acoustic waves than those that do not.

The model showed how those sound waves would have traveled through the water and indicated that they reached shore 15 to 20 minutes before the tsunami.

The team's model could apply to tsunami-forming fault zones around the world, though the characteristics of telltale acoustic signature might vary depending on the geology of the local environment.

The study is detailed in the current issue of the journal The Bulletin of the Seismological Society of America. (ANI)

Matches

MORE TOP STORIES TODAY

Kallis, Narine star in Knight Riders’ crushing win

Kallis, Narine star in Knight Riders’ crushing win

An all-round display saw Knight Riders thump Mumbai Indians by 41 runs in the IPL-7 opener. More »

Pietersen to miss Delhi's first game

Pietersen to miss Delhi's first game

The former England batsman will have to lead the franchise as he is out of the match against Bangalore with a finger injury. More »

Srinivasan named in fixing report: SC

Srinivasan named in fixing report: SC

The court emphasised that the tainted administrator can no longer work for the BCCI. More »

'If you do the wrong thing it will be found out'

'If you do the wrong thing it will be found out'

'Everyone knows what is right and what is wrong and if you do the wrong thing it will be found out' More »

Why I'm not looking forward to the IPL

Why I'm not looking forward to the IPL

Welcome to another season of a league that many watch but few trust. More »

Mitchell Johnson may quit T20s for Test cricket

Mitchell Johnson may quit T20s for Test cricket

Australia's Mitchell Johnson may quit limited-overs cricket to prolong his test career with an eye on the 2015 Ashes series in England, the fast bowler… More »

There's a lot going on: Fleming

There's a lot going on: Fleming

He experienced anxious moments in the lead-up to the tournament as the courts decided on whether to suspend the franchise, he said, but stressed that the… More »

Latif couldn’t work with tainted players

Latif couldn’t work with tainted players

Former Pakistan cricket captain Rashid Latif said Tuesday he turned down the job of national chief selector because he could not work with ex-players tainted… More »

We are not over-confident: Bailey

We are not over-confident: Bailey

Indian Premier League — George Bailey-led Kings XI Punjab will face Chennai Super Kings on Friday. More »

Taxing issue — BCCI hits roadblock

Taxing issue — BCCI hits roadblock

MoU between BCCI & its units to avoid double taxation delayed after a few decline to share details. More »

Big runs expected, with bat and ball

Big runs expected, with bat and ball

Royal Challengers Bangalore: Their main concern, once again, is the fast bowling More »

Black Caps pick rookie duo for West Indies

Black Caps pick rookie duo for West Indies

New Zealand selectors included two new caps in a 15-man Test squad named Tuesday to tour the West Indies, with injury-hit spinner Dan Vettori's future… More »

The stage is set for IPL-7 to start

The stage is set for IPL-7 to start

The Preview — Defending champions Mumbai Indians take on Kolkata Knight Riders More »

Srinivasan appeals to court to allow BCCI comeback

Srinivasan appeals to court to allow BCCI comeback

He was aggrieved by the allegations against him during the hearing. More »

Klinger on his exit from South Australia

Klinger on his exit from South Australia

Michael Klinger has revealed he felt compelled to leave South Australia after being told he would be only a fringe part of the Redbacks' plans for next season, and disputed the suggestion that he left… More »

India: cricket's Brazil

India: cricket's Brazil

They are tough to beat with a big talent base exposed to good facilities. (CYCSPL) More »

Delhi Daredevils say no to gifts

Delhi Daredevils say no to gifts

Franchises are doing their bit to refurbish the image of the tainted league. More »

India-Pakistan Test series likely in 2015

India-Pakistan Test series likely in 2015

The revival of Indo-Pak Test ties could take place in UAE. More »

Kohli hopes to end RCB trophy drought

Kohli hopes to end RCB trophy drought

'This time around we will hope to go few more steps ahead and actually get that trophy' More »

Gavaskar can help IPL regain glory

Gavaskar can help IPL regain glory

Apart from the foreign players a lot of behind-the-scene activity has taken place in selecting the Indian domestic players. More »

Tendulkar, Ganguly to promote soccer

Tendulkar, Ganguly to promote soccer

Leading Spanish club Atletico Madrid and former cricketers Sachin Tendulkar and Sourav Ganguly are among the owners of eight franchises of a new Indian… More »

This isn’t my first trip to India: Neesham

This isn’t my first trip to India: Neesham

Kiwi all-rounder wants to utilise the India leg to explore the country’s tourist attractions. More »

Ishant wanted to quit ODIs

Ishant wanted to quit ODIs

Says his mother made him change his mind. More »