Featured Research

from universities, journals, and other organizations

Speed gun for Earth's insides to help measure mantle motion

Date:
October 28, 2010
Source:
University of Bristol
Summary:
Researchers have developed a seismological "speed gun" for the inside of Earth. Using this technique they will be able to measure the way the Earth's deep interior slowly moves around. This mantle motion is what controls the location of our continents and oceans, and where the tectonic plates collide to shake the surface we live on.

"This study focusses on a mysterious layer where the mantle meets the core, a sphere of iron at the centre of the Earth 7,000 km (4400 miles) across. This part just above the core has curious properties which we can measure using seismic waves that pass through it," Andy Nowacki said.
Credit: iStockphoto/Baris Simsek

Researchers at the University of Bristol have reveal in the journal Nature that they have developed a seismological 'speed gun' for the inside of Earth. Using this technique they will be able to measure the way Earth's deep interior slowly moves around. This mantle motion is what controls the location of our continents and oceans, and where the tectonic plates collide to shake the surface we live on.

For 2,900 km (1800 miles) beneath our feet, Earth is made of the rocky mantle. Although solid, it is so hot that it can flow like putty over millions of years. It is heated from below, so that it circulates like water on a stove. While geophysicists know something about how the material moves by the time it reaches the top of the mantle, what goes on at the bottom is still a puzzle. However researchers need to know both to predict how the Earth's surface -- our home -- will behave.

Andy Nowacki, at the School of Earth Sciences at Bristol University, explained: "The only way to measure the inside of the Earth at such huge depths is with seismic waves. When a large earthquake occurs and waves travel through the Earth, they are affected in different ways, and we can examine their properties to work out what is happening thousands of miles beneath our feet, a region where we can never go. This study focusses on a mysterious layer where the mantle meets the core, a sphere of iron at the centre of the Earth 7,000 km (4400 miles) across. This part just above the core has curious properties which we can measure using seismic waves that pass through it."

This enigmatic part of Earth is known as D″ (pronounced 'dee-double-prime'). Dr James Wookey said: "We believe that D″ is made from crystals which line up in a certain orientation when the mantle flows. We can measure how they line up, and in this study we do this for one part of the world -- North and Central America. In the future our method can then be used to see which direction the mantle is moving everywhere."

Professor Mike Kendall added: "This part of the Earth is incredibly important. The lowermost mantle is where two colossal, churning engines -- the mantle and the core -- meet and interact. The core is moving very quickly and creates our magnetic field which protects us from the Sun's rays. The mantle above is sluggish, but drives the motion of the plates on the Earth's surface, which build mountains, feed volcanoes and cause earthquakes. Measuring the flow in the lowermost mantle is vital to understanding the long term evolution of the Earth."


Story Source:

The above story is based on materials provided by University of Bristol. Note: Materials may be edited for content and length.


Journal Reference:

  1. Andy Nowacki, James Wookey, J-Michael Kendall. Deformation of the lowermost mantle from seismic anisotropy. Nature, 2010; 467 (7319): 1091 DOI: 10.1038/nature09507

Cite This Page:

University of Bristol. "Speed gun for Earth's insides to help measure mantle motion." ScienceDaily. ScienceDaily, 28 October 2010. <www.sciencedaily.com/releases/2010/10/101027133152.htm>.
University of Bristol. (2010, October 28). Speed gun for Earth's insides to help measure mantle motion. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2010/10/101027133152.htm
University of Bristol. "Speed gun for Earth's insides to help measure mantle motion." ScienceDaily. www.sciencedaily.com/releases/2010/10/101027133152.htm (accessed October 2, 2014).

Share This



More Earth & Climate News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: 12 More Bodies Found on Japan Volcano

Raw: 12 More Bodies Found on Japan Volcano

AP (Oct. 1, 2014) — A dozen more bodies were found Wednesday as Japanese rescuers resumed efforts to find survivors and retrieve bodies of those trapped by Mount Ontake's eruption. (Oct. 1) Video provided by AP
Powered by NewsLook.com
Cultural Learning In Wild Chimps Observed For The First Time

Cultural Learning In Wild Chimps Observed For The First Time

Newsy (Oct. 1, 2014) — Cultural transmission — the passing of knowledge from one animal to another — has been caught on camera with chimps teaching other chimps. Video provided by Newsy
Powered by NewsLook.com
Raw: Trapped Scientist Rescued from Cave in Peru

Raw: Trapped Scientist Rescued from Cave in Peru

AP (Oct. 1, 2014) — A Spanish scientist, who spent 12 days trapped about 1300 feet underground in a cave in Peru's remote Amazon region, was rescued on Tuesday. (Oct. 1) Video provided by AP
Powered by NewsLook.com
Media, Industry Groups React To Calif. Plastic Bag Ban

Media, Industry Groups React To Calif. Plastic Bag Ban

Newsy (Sep. 30, 2014) — California is the first state in the country to ban single-use plastic bags in grocery, liquor and convenience stores. 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