Scientists shed light on make-up of Earth's core

March 12, 2019, University of Edinburgh
Credit: CC0 Public Domain

Experiments conducted at extreme conditions are giving scientists new insights into the chemical make-up of the Earth's core.

Advanced laboratory techniques reveal that our planet's metal centre – more than 1,800 miles below the surface – also contains , an element commonly found in stony meteorites.

The findings support an existing theory that suggests Earth's formation around 4.5 billion years ago was driven by extensive interactions between stony and iron-rich meteorites inside a cloud of dust and gas. This huge cloud of material also formed the Sun.

Chemical make-up

The chemical composition of the Earth's core is still poorly understood, despite more than 60 years of research, scientists say.

Previous studies had suggested the core is composed of an alloy of iron and nickel, though other elements are thought to be present.

Extreme conditions

A team led by experts from the University made the discovery by inserting tiny mixtures of iron, nickel and silicon into a device known as a diamond anvil cell. It can recreate the extreme pressures and temperatures present deep inside planets.

By squeezing the mixture together, they were able to achieve the same density as that found at the Earth's core.

The scientists predict that the temperature at the planet's centre exceeds 5500 degrees Celsius.

International team

Experiments were conducted at the Deutsches Elektronen-Synchrotron, Germany, and the European Synchrotron Radiation Facility in France.

The study, published in the journal Earth and Planetary Science Letters, received funding from the European Research Council. The work also involved researchers from the University of Bayreuth, Germany, and Hiroshima and Osaka Universities in Japan.

The nature of the Earth's core is the key to understanding a number of processes operating inside the planet. Our findings are an important step towards understanding how the planet was formed and how it may evolve in the future, says Dr. Tetsuya Komabayashi, School of GeoSciences.

Explore further: Laser experiments shed light on Earth's core

More information: Tetsuya Komabayashi et al. Phase relations in the system Fe–Ni–Si to 200 GPa and 3900 K and implications for Earth's core, Earth and Planetary Science Letters (2019). DOI: 10.1016/j.epsl.2019.01.056

Related Stories

Just what sustains Earth's magnetic field anyway?

June 1, 2016

Earth's magnetic field shields us from deadly cosmic radiation, and without it, life as we know it could not exist here. The motion of liquid iron in the planet's outer core, a phenomenon called a "geodynamo," generates the ...

Experiment suggests silicon missing element in Earth's core

January 11, 2017

(Phys.org)—A team of researchers from several institutions in Japan has conducted experiments with results that indicate that silicon is likely the missing element in Earth's core. The group gave a presentation outlining ...

Recommended for you

Coffee-based colloids for direct solar absorption

March 22, 2019

Solar energy is one of the most promising resources to help reduce fossil fuel consumption and mitigate greenhouse gas emissions to power a sustainable future. Devices presently in use to convert solar energy into thermal ...

Paleontologists report world's biggest Tyrannosaurus rex

March 22, 2019

University of Alberta paleontologists have just reported the world's biggest Tyrannosaurus rex and the largest dinosaur skeleton ever found in Canada. The 13-metre-long T. rex, nicknamed "Scotty," lived in prehistoric Saskatchewan ...

0 comments

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.