Liverpool scientist discovers new layer of the Earth

Apr 14, 2005

A University of Liverpool scientist has discovered a new layer near the Earth's core, which will enable the internal temperature of the Earth's mantle to be measured at a much deeper level than previously possible.

Dr Christine Thomas, from the Department of Earth Sciences, has found a previously undetected seismic layer near the Earth's core-mantle boundary. Her discovery will allow geophysicists to measure variations in the Earth's internal temperature near the boundary between the rocky mantle and fluid core, about 2,900 km below the Earth's surface.

Dr Thomas developed a model with colleagues at University of California Los Angeles (UCLA), which uses a recently discovered phase change (when atoms are compressed into crystals under high pressure) in the lowest part of the Earth's mantle. They propose that temperature changes in this area can result in the creation of two seismic layers near the core-mantle boundary, the second of which has been recently discovered by Dr Thomas.

The two seismic layers can provide a sensitive thermometer with which researchers can take the temperature of the Earth's lowermost mantle. The layers also enable scientists to examine whether cold subducted lithosphere (cold areas beneath a plate which can cause earthquakes) is reaching the core-mantle boundary, and whether hot material rises from the area between the core and mantle.

In the first case, the two seismic layers should be visible in seismic waves that travel through the Earth; the latter case would not show any layers. This would be a strong case for the convection of the whole mantle that is still a highly debated issue in the Earth Sciences.

Dr Thomas said: "Our discovery marks an exciting stage in earth science research as it provides the possibility to test the debated issue of whole mantle convection, the largely unconstrained heat flow from the Earth's core to the mantle and the fate of subducted lithosphere with seismic data."

Source: University of Liverpool

Explore further: Scars on Mars from 2012 rover landing fade—usually

add to favorites email to friend print save as pdf

Related Stories

Seismic study aims to map Earth's interior in 3-D

Mar 16, 2015

When a 7.9-magnitude earthquake struck central China's Sichuan province in 2008, seismic waves rippled through the region, toppling apartment houses in the city of Chengdu and swaying office buildings 1,000 ...

To speed up magma, add water

Feb 02, 2015

It was a bit like making a CT scan of a patient's head and finding he had very little brain or making a PET scan of a dead fish and seeing hot spots of oxygen consumption. Scientists making seismic images ...

New study reveals insights on plate tectonics

Mar 04, 2014

(Phys.org) —The Earth's outer layer is made up of a series of moving, interacting plates whose motion at the surface generates earthquakes, creates volcanoes and builds mountains. Geoscientists have long ...

Recommended for you

Europe resumes Galileo satnav deployment (Update)

Mar 27, 2015

Europe resumed deployment of its beleaguered Galileo satnav programme on Friday, launching a pair of satellites seven months after a rocket malfunction sent two multi-million euro orbiters awry.

More evidence for groundwater on Mars

Mar 27, 2015

Monica Pondrelli and colleagues investigated the Equatorial Layered Deposits (ELDs) of Arabia Terra in Firsoff crater area, Mars, to understand their formation and potential habitability. On the plateau, ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.