Nav: Home

'Quartz' crystals at the Earth's core power its magnetic field

February 22, 2017

The Earth's core consists mostly of a huge ball of liquid metal lying at 3000 km beneath its surface, surrounded by a mantle of hot rock. Notably, at such great depths, both the core and mantle are subject to extremely high pressures and temperatures. Furthermore, research indicates that the slow creeping flow of hot buoyant rocks--moving several centimeters per year--carries heat away from the core to the surface, resulting in a very gradual cooling of the core over geological time. However, the degree to which the Earth's core has cooled since its formation is an area of intense debate amongst Earth scientists.

In 2013 Kei Hirose, now Director of the Earth-Life Science Institute (ELSI) at the Tokyo Institute of Technology (Tokyo Tech), reported that the Earth's core may have cooled by as much as 1000?C since its formation 4.5 billion years ago. This large amount of cooling would be necessary to sustain the geomagnetic field, unless there was another as yet undiscovered source of energy. These results were a major surprise to the deep Earth community, and created what Peter Olson of Johns Hopkins University referred to as, "the New Core Heat Paradox", in an article published in Science.

Core cooling and energy sources for the geomagnetic field were not the only difficult issues faced by the team. Another unresolved matter was uncertainty about the chemical composition of the core. "The core is mostly iron and some nickel, but also contains about 10% of light alloys such as silicon, oxygen, sulfur, carbon, hydrogen, and other compounds," Hirose, lead author of the new study to be published in the journal Nature [1]. "We think that many alloys are simultaneously present, but we don't know the proportion of each candidate element."

Now, in this latest research carried out in Hirose's lab at ELSI, the scientists used precision cut diamonds to squeeze tiny dust-sized samples to the same pressures that exist at the Earth's core (Fig. 1). The high temperatures at the interior of the Earth were created by heating samples with a laser beam. By performing experiments with a range of probable alloy compositions under a variety of conditions, Hirose's and colleagues are trying to identify the unique behavior of different alloy combinations that match the distinct environment that exists at the Earth's core.

The search of alloys began to yield useful results when Hirose and his collaborators began mixing more than one alloy. "In the past, most research on iron alloys in the core has focused only on the iron and a single alloy," says Hirose. "But in these experiments we decided to combine two different alloys containing silicon and oxygen, which we strongly believe exist in the core."

The researchers were surprised to find that when they examined the samples in an electron microscope, the small amounts of silicon and oxygen in the starting sample had combined together to form silicon dioxide crystals (Fig. 2)--the same composition as the mineral quartz found at the surface of the Earth.

"This result proved important for understanding the energetics and evolution of the core," says John Hernlund of ELSI, a co-author of the study. "We were excited because our calculations showed that crystallization of silicon dioxide crystals from the core could provide an immense new energy source for powering the Earth's magnetic field." The additional boost it provides is plenty enough to solve Olson's paradox.

The team has also explored the implications of these results for the formation of the Earth and conditions in the early Solar System. Crystallization changes the composition of the core by removing dissolved silicon and oxygen gradually over time. Eventually the process of crystallization will stop when then core runs out of its ancient inventory of either silicon or oxygen.

"Even if you have silicon present, you can't make silicon dioxide crystals without also having some oxygen available" says ELSI scientist George Helffrich, who modeled the crystallization process for this study. "But this gives us clues about the original concentration of oxygen and silicon in the core, because only some silicon:oxygen ratios are compatible with this model."

Tokyo Institute of Technology

Related Magnetic Field Articles:

Understanding stars: How tornado-shaped flow in a dynamo strengthens the magnetic field
A new simulation based on the von-Kármán-Sodium (VKS) dynamo experiment takes a closer look at how the liquid vortex created by the device generates a magnetic field.
'Quartz' crystals at the Earth's core power its magnetic field
Scientists at the Earth-Life Science Institute at the Tokyo Institute of Technology report in Nature (Fen.
Brightest neutron star yet has a multipolar magnetic field
Scientists have identified a neutron star that is consuming material so fast it emits more x-rays than any other.
Confirmation of Wendelstein 7-X magnetic field
Physicist Sam Lazerson of the US Department of Energy's Princeton Plasma Physics Laboratory has teamed with German scientists to confirm that the Wendelstein 7-X fusion energy device called a stellarator in Greifswald, Germany, produces high-quality magnetic fields that are consistent with their complex design.
High-precision magnetic field sensing
Scientists have developed a highly sensitive sensor to detect tiny changes in strong magnetic fields.
Brilliant burst in space reveals universe's magnetic field
Scientists have detected the brightest fast burst of radio waves in space to date -- locating the source of the event with more precision than previous efforts.
Optical magnetic field sensor can detect signals from the nervous system
The human body is controlled by electrical impulses in the brain, the heart and nervous system.
What did Earth's ancient magnetic field look like?
New work from Carnegie's Peter Driscoll suggests Earth's ancient magnetic field was significantly different than the present day field, originating from several poles rather than the familiar two.
Just what sustains Earth's magnetic field anyway?
Earth's magnetic field shields us from deadly cosmic radiation, and without it, life as we know it could not exist here.
Ironing out the mystery of Earth's magnetic field
The Earth's magnetic field has been existing for at least 3.4 billion years thanks to the low heat conduction capability of iron in the planet's core.

Related Magnetic Field Reading:

Know Your Magnetic Field: Change Your Thinking, Change Your Life.
by William E. Gray (Author)

“We mortals operate on wave lengths from the Universal, the Trinity; these are our life waves. They are distributed, one wave from each of the ruling suns. Each of our waves is on a set length or frequency; the blending of the three waves is the Power. This sets the pattern of our individual frequency. It is the source of our personality, our identity and it is as distinct and individual as our own finger-prints. “On the strength of our wave we, similar to a planet, operate by our magnetic field through the medium and receive the knowledge we need from the vast pool of wisdom. It is... View Details

Magnetic Field(s)
by Ron Loewinsohn (Author), Steve Erickson (Preface)

Organized around the idea that "you can't know what a magnetic field is like unless you're inside of it, " Ron Loewinsohn's first novel opens from the disturbing perspective of a burglar in the midst of a robbery and travels through the thoughts and experiences (both real and imaginary) of a group of characters whose lives are connected both coincidentally and intimately. All of the characters have a common desire to imagine and invent rather horrifying stories about the lives of people around them. As the novel develops, certain phrasings and images recur improbably, drawing the reader into... View Details

Power Tools for Health: How Pulsed Magnetic Fields (Pemfs) Help You
by Msc William Pawluk MD (Author), Caitlin Layne (Author)

Power tools revolutionized the building of your family home.
Now they will revolutionize your health.

Power Tools for Health will teach you to how to:
- treat new or chronic health conditions like pain, anxiety, insomnia, diabetes and injuries
- avoid annoying or potentially harmful side effects from pharmaceuticals or other treatments
- enhance and accelerate recovery from surgery

Research shows PEMFs accelerate the healing of almost any cell, tissue, organ, or condition.
Unlike much of modern medicine, which mostly focuses on symptom... View Details

Magnetic Fields: A Comprehensive Theoretical Treatise for Practical Use
by Heinz E. Knoepfel (Author)

A unique resource for physicists and engineers working with magnetic fields
An understanding of magnetic phenomena is essential for anyone working on the practical application of electromagnetic theory. Magnetic Fields: A Comprehensive Theoretical Treatise for Practical Use provides physicists and engineers with a thorough treatment of the magnetic aspects of classical electromagnetic theory, focusing on key issues and problems arising in the generation and application of magnetic fields. From magnetic potentials and diffusion phenomena to magnetohydrodynamics and properties of... View Details

Magnetic Fields: Expanding American Abstraction, 1960s to Today
by Valerie Cassel Oliver (Author), Lowery Stokes Sims (Author), Erin Dziedzic (Editor), Melissa Messina (Editor)

In the history of American art, the contributions of African American artists to the development of abstraction have been largely overlooked.

Magnetic Fields aims to change this perspective by focusing on nonrepresentational work by women artists of color, presenting a more complete presentation of American abstraction than has previously been offered.

Intergenerational in scope, Magnetic Fields includes more than 20 artists born between 1891 and 1981, among them Lilian Thomas Burwell, Mildred Thompson, Candida Alvarez, Betty Blayton, Nanette... View Details

Reconnection of Magnetic Fields: Magnetohydrodynamics and Collisionless Theory and Observations
by J. Birn (Editor), E. R. Priest (Editor)

The reconnection of magnetic fields is one of the most fascinating processes in plasma physics, responsible for phenomena such as solar flares and magnetospheric substorms. The concept of reconnection has developed through recent advances in exploring the magnetospheres of the Sun and Earth through theory, computer simulations and spacecraft observations. The great challenge in understanding it stems from balancing the large volumes of plasma and magnetic fields involved with the energy release with the physical mechanism which relies on the strongly localized behavior of charged particles.... View Details

NOW 2 kNOW Electro-Magnetic Fields
by Dr. T G D'Alberto (Author)

You're taking a challenging EM Fields course or simimlar while balancing umpteen other classes and maybe even a job. Your chief concern is to figure out, in the shortest time possible, how to successfully do the homework and exam problems. So, let’s get to it. The main stumbling blocks that trip up most students are conquered by a three-time teaching assistant to this course at Cornell. Get the help those students got! From a review of vector calculus to descriptions of the physics behind the math to detailed examples, this book is a must-have companion to any course addressing EM Fields.... View Details

The Magnetic Fields
by André Breton (Author), Philippe Soupault (Author), David Gascoyne (Translator)

tr David Gascoyne View Details

Conversations on Electric and Magnetic Fields in the Cosmos (Princeton Series in Astrophysics)
by Eugene Parker (Author)

Today's standard textbooks treat the theoretical structure of electric and magnetic fields, but their emphasis is on electromagnetic radiation and static-electric and magnetic fields. In this book, Eugene Parker provides advanced graduate students and researchers with a much-needed complement to existing texts, one that discusses the dynamic electromagnetism of the cosmos--that is, the vast magnetic fields that are carried bodily in the swirling ionized gases of stars and galaxies and throughout intergalactic space.

Parker is arguably the world's leading authority on solar wind... View Details

Magnetic Fields' 69 Love Songs: A Field Guide (33 1/3)
by LD Beghtol (Author), Ken Emerson (Introduction)

A fully illustrated oral history of the Magnetic Fields' 1999 triple album, 69 Love Songs - an album that was afforded "classic" status by many almost as soon as it was released. LD Beghtol's book is chatty, incestuous, funny, dark, digressive, sexy, maddening, and delightful in equal measures. It documents a vital and influential scene from the inside, involving ukuleles and tears, citations and footnotes, analogue drum machines, and floods of cognac. Oh, and a crossword puzzle too.

The centre of the book is the secret history of these tuneful, acerbic, and sometimes... View Details

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

The Person You Become
Over the course of our lives, we shed parts of our old selves, embrace new ones, and redefine who we are. This hour, TED speakers explore ideas about the experiences that shape the person we become. Guests include aerobatics pilot and public speaker Janine Shepherd, writers Roxane Gay and Taiye Selasi, activist Jackson Bird, and fashion executive Kaustav Dey.
Now Playing: Science for the People

#478 She Has Her Mother's Laugh
What does heredity really mean? Carl Zimmer would argue it's more than your genes along. In "She Has Her Mother’s Laugh: The Power, Perversions, and Potential of Heredity", Zimmer covers the history of genetics and what kinship and heredity really mean when we're discovering how to alter our own DNA, and, potentially, the DNA of our children.