Research finds clues to uncanny electrical conductivity in Earth's mantle

May 9, 2016 by Anne M Stark
Researchers have found that the dehydration of chlorite is likely crucial in explaining the high electrical conductivity observed in the Earth’s mantle. Image courtesy of Johan Swanepoel via Getty Images

A team of scientists, including one at Lawrence Livermore National Laboratory (LLNL), has found that the dehydration of chlorite is likely to be crucial in explaining the anomalously high electrical conductivity observed in the Earth's mantle.

The high (EC) in the mantle wedge regions between depths of 40 and 100 km is often attributed to the aqueous fluid released from descending slabs. It is well known that mantle silicate minerals are electrical insulators with large electronic band gaps of around 7.5 to 9.5 electron volts (eV) at room temperature.

Laboratory-based measurements of the electrical conductivity of hydrous phases and aqueous fluids are significantly lower and cannot readily explain the geophysically observed high electrical conductivity. The released aqueous fluid also rehydrates the mantle wedge and stabilizes a suite of hydrous phases, including serpentine and chlorite.

The new research, appearing in the May 6 edition of the journal Science Advances, shows that the EC of chlorite is similar to other hydrous silicate minerals. The EC has a weak or no-pressure dependence but varies significantly with temperature.

"We have measured the electrical conductivity of a natural chlorite at pressures and temperatures relevant for the subduction zone setting," said Davide Novella, a geophysicist at LLNL. "In our experiment, we observed two distinct conductivity enhancements when chlorite is heated to temperatures beyond its thermodynamic stability field. The initial increase in electrical conductivity can be attributed to chlorite dehydration and the release of aqueous fluids. This is followed by a unique, subsequent enhancement of electrical conductivity."

The team found that the further increase in EC is related to the growth of an interconnected network of highly conductive and chemically impure magnetite mineral phases.

"The dehydration of chlorite and associated processes are likely to be crucial in explaining the anomalously observed in mantle wedges," Novella said. "Chlorite dehydration in the mantle wedge provides an additional source of aqueous fluid above the slab and also could be responsible for the fixed depth (120 ± 40 km) of melting at the top of the subducting slab."

Explore further: Experimental study of the electrical conductivity of hydrous minerals under high P-T conditions

More information: G. Manthilake et al. Dehydration of chlorite explains anomalously high electrical conductivity in the mantle wedges, Science Advances (2016). DOI: 10.1126/sciadv.1501631

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katesisco
1 / 5 (11) May 09, 2016


Consider:

Our solar system past implicates a wandering systems body that impinges upon our system irregularly to disrupt mechanics. Altho we find only implications but no evidence.. What if our sun Sol, experiences a magnetic alignment that produces a magnetic refraction that appears in the sky as a solar shade of our sun? And then Sol would actually be the producer of the 'thunderbolts of the gods' that strike the Earth while the magnetic shade ONLY appears to be involved?
This is not so strange as it may at first seem as science regularly relies on the 'lensing' phenomena that allows distances to be arbitrarily assigned by science. Observers see the bent light and say gravity but it is magnetism. Here on Earth NASA says magnetic reconnection regarding HOT FLOW ANOMALIES and the transference of magnetic energy to kinetic energy.
AGreatWhopper
3.7 / 5 (15) May 09, 2016
I guess if you believe that crap you'd believe you're informing someone. We get this every time electricity is mentioned in the title and the crackpots foul the thread as predictably and constructively as flies at a picnic.

Shoo!
torbjorn_b_g_larsson
5 / 5 (13) May 10, 2016
"Consider [meaningless blather]."

Considered, rejected as containing nothing resembling known facts*, done.

Having "electrical" in the title is, as already noted, troll bait. Sigh.

*E.g. "Our solar system past implicates a wandering systems body that impinges upon our system irregularly to disrupt mechanics."

The fossil record shows that no such interruption, regular or irregular, happened.

And it gets only worse from there.
HannesAlfven
1 / 5 (11) May 10, 2016
Not that I am a fan of what was posted above, but it's important to understand that a number of animals from multiple continents went extinct at around the same time as the mammoths (some say around 12k years ago, but people differ on these dates).

Further, the Firestone group has also found 8 instances of mammoth tusks peppered with meteorites, as well as a mammoth carcass draped with a black radioactive mat filled with exotic isotopes. When you also count in the hollow spherules that contain nano-diamonds inside of them, it is very clear that some sort of recent event did indeed occur.

People who try so hard to ignore the pictures of all of these observations are simply fooling themselves. And for what? To create a false sense of complacency?

You might consider taking a moment to just think about what you are saying and doing. Get the Firestone book and look at the images yourself.
cantdrive85
1 / 5 (13) May 10, 2016
Seems as if Tesla was aware of this many decades ago.
"So astounding are the facts in this connection, that it would seem as though the Creator, himself had electrically designed this planet..."

"...the idea gradually took hold of me that the earth might be used in place of the wire, thus dispensing with artificial conductors altogether. The immensity of the globe seemed an unsurmountable obstacle but after a prolonged study of the subject I became satisfied that the undertaking was rational..."
HannesAlfven
1 / 5 (11) May 10, 2016
Would be very nice to understand why the Earth cannot have a charge to it like every other iron ball.
john berry_hobbes
3.5 / 5 (11) May 14, 2016
HannesAlfven

1 /5 (6) May 10, 2016
Further, the Firestone group has also found 8 instances of mammoth tusks peppered with meteorites,


No, they didn't, you clueless crank. That was debunked eight years ago. Try keeping up. Oh, but that would mean reading comprehension and not projecting your delusions onto any con that comes along. http://www.swanet...2008.pdf

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