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: Lockheed Martin successfully mates NOAA GOES-R satellite modules

add to favorites email to friend print save as pdf

Related Stories

Textbook theory behind volcanoes may be wrong

Sep 08, 2014

In the typical textbook picture, volcanoes, such as those that are forming the Hawaiian islands, erupt when magma gushes out as narrow jets from deep inside Earth. But that picture is wrong, according to ...

Mantle plumes crack continents

Sep 04, 2014

Using a simulation with an unprecedentedly high resolution, Earth scientists from University of Paris VI and ETH Zurich have shown that magma columns in the Earth's interior can cause continental breakup—but ...

New view of Rainier's volcanic plumbing

Jul 17, 2014

By measuring how fast Earth conducts electricity and seismic waves, a University of Utah researcher and colleagues made a detailed picture of Mount Rainier's deep volcanic plumbing and partly molten rock ...

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

The Great Cold Spot in the cosmic microwave background

11 hours ago

The cosmic microwave background (CMB) is the thermal afterglow of the primordial fireball we call the big bang. One of the striking features of the CMB is how remarkably uniform it is. Still, there are some ...

Winter in the southern uplands of Mars

11 hours ago

Over billions of years, the southern uplands of Mars have been pockmarked by numerous impact features, which are often so closely packed that they overlap. One such feature is Hooke crater, shown in this ...

Five facts about NASA's ISS-RapidScat

11 hours ago

NASA's ISS-RapidScat mission will observe ocean wind speed and direction over most of the globe, bringing a new eye on tropical storms, hurricanes and typhoons. Here are five fast facts about the mission.

User comments : 0