Featured Research

from universities, journals, and other organizations

New Technique Uses Seismic 'Garbage' To View Earth's Interior

Date:
March 30, 2005
Source:
National Science Foundation
Summary:
Seismologists have long relied on earthquakes or expensive tools like explosives to help create images of Earth’s interior, but a new method created by University of Colorado at Boulder (CU-Boulder) researchers will produce quicker, cheaper and clearer images.

Maps of the speed of seismic surface waves with periods from 7.5 to 18 seconds cross Southern California.
Credit: University of Colorado at Boulder

Seismologists have long relied on earthquakes or expensive tools like explosives to help create images of Earth’s interior, but a new method created by University of Colorado at Boulder (CU-Boulder) researchers will produce quicker, cheaper and clearer images.

Rather than waiting for earthquakes, the researchers have recovered surface-wave information from normal seismic noise that is constantly produced by fluctuations in the Earth’s atmosphere and oceans. Measuring surface waves is important because the information helps scientists get a clearer picture of the Earth’s interior, according to Michael Ritzwoller, director of CU-Boulder’s Center for Imaging the Earth’s Interior.

The method is described in the March 11 issue of the journal Science.

“This new technique will give us a better fundamental understanding of the planet by providing much better resolution of Earth’s interior,” Ritzwoller said. “It also will diminish what is known in seismology as the ‘tyranny of earthquakes,’ which means having to wait for an earthquake to happen to do our jobs."

The new method promises significant improvements in the resolution and accuracy of crust and upper mantle images down to 60 miles or more within the Earth, particularly when used with seismic projects like USArray, according to Nikolai Shapiro, a research associate in the Center for Imaging the Earth’s Interior and the study’s chief author.

Coupled with existing and emerging technology, such as USArray, the new measuring technique will lead to a better fundamental understanding of the structure of the planet and may help save lives in the process, Ritzwoller said. A component of the National Science Foundation's (NSF) EarthScope program, USArray includes hundreds of portable seismometers that in coming years will be moved over the entire country, producing images of the Earth’s interior to aid in earthquake risk assessment.

"The authors' application of what used to be 'seismic noise' to the detailed mapping of the crust and upper mantle will have significant impact on earth science and on seismic hazard mitigation," says James Whitcomb, head of NSF's deep earth processes section, which funded the research. "This innovative research foretells what's to come from EarthScope."

Researchers have for years been constructing tomographic images of Earth’s crust and upper mantle from waves generated by earthquakes. That method, known as seismic tomography, reconstructs Earth’s inner structure on a computer screen, slice by slice. The new technique is similar, but is based on organizing ambient seismic noise, which is typically discarded as seismic "garbage."

Seismic tomography is like doing a medical CT scan of the Earth, Ritzwoller said. But when people have a CT scan, doctors are in control and can make images at will. Seismologists can’t control when an earthquake happens, so they can either wait for another one or set off explosives to create their own image-generating waves.

“To move beyond these limitations requires observational methods based on seismic sources other than earthquakes, which is what our method offers,” said Shapiro.


Story Source:

The above story is based on materials provided by National Science Foundation. Note: Materials may be edited for content and length.


Cite This Page:

National Science Foundation. "New Technique Uses Seismic 'Garbage' To View Earth's Interior." ScienceDaily. ScienceDaily, 30 March 2005. <www.sciencedaily.com/releases/2005/03/050325154427.htm>.
National Science Foundation. (2005, March 30). New Technique Uses Seismic 'Garbage' To View Earth's Interior. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2005/03/050325154427.htm
National Science Foundation. "New Technique Uses Seismic 'Garbage' To View Earth's Interior." ScienceDaily. www.sciencedaily.com/releases/2005/03/050325154427.htm (accessed October 22, 2014).

Share This



More Earth & Climate News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Traditional Farming Methods Gaining Ground in Mali

Traditional Farming Methods Gaining Ground in Mali

AFP (Oct. 20, 2014) He is leading a one man agricultural revolution in Mali - Oumar Diatabe uses traditional farming methods to get the most out of his land and is teaching others across the country how to do the same. Duration: 01:44 Video provided by AFP
Powered by NewsLook.com
How Detroit's Money Woes Led To U.N.-Condemned Water Cutoffs

How Detroit's Money Woes Led To U.N.-Condemned Water Cutoffs

Newsy (Oct. 20, 2014) The United Nations says water is a human right, but should it be free? Detroit has cut off water to residents who can't pay, and the U.N. isn't happy. Video provided by Newsy
Powered by NewsLook.com
Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

3BL Media (Oct. 20, 2014) Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-fuel Impala Video provided by 3BL
Powered by NewsLook.com
White Rhino's Death In Kenya Means Just 6 Are Left

White Rhino's Death In Kenya Means Just 6 Are Left

Newsy (Oct. 20, 2014) Suni, a rare northern white rhino at Ol Pejeta Conservancy, died Friday. This, as many media have pointed out, leaves people fearing extinction. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins