Scientists uncover huge reservoir of melting carbon under Western United States

February 13, 2017, Royal Holloway, University of London

New research published in Earth and Planetary Science Letters describes how scientists have used the world's largest array of seismic sensors to map a deep-Earth area of melting carbon covering 1.8 million square kilometres. Situated under the Western US, 350km beneath the Earth's surface, the discovered melting region challenges accepted understanding of how much carbon the Earth contains – much more than previously understood.

The study, conducted by geologist at Royal Holloway, University of London's Department of Earth Sciences used a huge network of 583 that measure the Earth's vibrations, to create a picture of the area's deep sub surface. Known as the , this section of the Earth's interior is recognised by its high temperatures where solid carbonates melt, creating very particular seismic patterns.

"It would be impossible for us to drill far enough down to physically 'see' the Earth's mantle, so using this massive group of sensors we have to paint a picture of it using mathematical equations to interpret what is beneath us," said Dr Sash Hier-Majumder of Royal Holloway.

He continued, "Under the western US is a huge underground partially-molten reservoir of liquid carbonate. It is a result of one of the tectonic plates of the Pacific Ocean forced underneath the western USA, undergoing partial melting thanks to gasses like CO2 and H2O contained in the minerals dissolved in it."

As a result of this study, scientists now understand the amount of CO2 in the Earth's upper mantle may be up to 100 trillion metric tons. In comparison, the US Environmental Protection Agency estimates the global carbon emission in 2011 was nearly 10 billion metric tons – a tiny amount in comparison. The deep carbon reservoir discovered by Dr. Hier-Majumder will eventually make its way to the surface through volcanic eruptions, and contribute to climate change albeit very slowly.

"We might not think of the deep structure of the Earth as linked to climate change above us, but this discovery not only has implications for subterranean mapping but also for our future atmosphere," concluded Dr Hier-Majumder,"For example, releasing only 1% of this CO2 into the atmosphere will be the equivalent of burning 2.3 trillion barrels of oil. The existence of such deep reservoirs show how important is the role of deep Earth in the cycle."

Explore further: Deep mantle chemistry surprise: Carbon content not uniform

More information: Saswata Hier-Majumder et al. Pervasive upper mantle melting beneath the western US, Earth and Planetary Science Letters (2017). DOI: 10.1016/j.epsl.2016.12.041

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11 comments

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FactsReallyMatter
1.5 / 5 (15) Feb 13, 2017
No problem, this is magic CO2. Apparently it can be emitted naturally and therefore will only maintain the earth in perfect balance. Not like that nasty man-made CO2 which only causes death and destruction.
Benni
1.7 / 5 (11) Feb 13, 2017
it takes a lot of brass on the part of real scientists to put together a report like this. Can't they figure out this only upsets the AGW Enthusiasts? Well, maybe they do, and that is why this was published.

philstacy9
2.8 / 5 (9) Feb 13, 2017
"releasing only 1% of this CO2 into the atmosphere"
If carbon "350km beneath the Earth's surface" is in danger of being released sequestration at shallow depths looks like fail.
Osiris1
1 / 5 (2) Feb 13, 2017
If this carbon in part produced by the action of life processes, then it becomes logical to conjecture on intelligent life in the remote past.... or at least semiintelligent life. Now if a dino with a gift of gab called Donaldus Diploadicuss was a dino politician in that lost continent like the theory of 'Tro-Odon' could have posited, then lots of CO2 and CO could have been generated from frontulence and flatulence from the rot of all the efronteries, prevarications, and 'fake news' from their politcical public relations mouthpieces like maybe an ancient newscasters of the time like Skellie Pachycephalosaurus with her T-Rex teeth and Alabama Slatern Formation blonde scales. LOL. Anyway had to be hot times in the olde towne back then.
humy
4.6 / 5 (10) Feb 14, 2017
This carbon is atmospherically released so extremely slowly via volcanism over many million of years thus giving ample time for it to be reabsorbed back into carbonates that it has no short term relevance to the the man made atmospherically released carbon in recent years as that man made release in the last few years completely dwarfs that released be volcanoes in the last few years. In other words, it is the massively higher RATE of atmospheric release here that is the problem with man made sources compared to that of natural sources. This is something the religious likes of FactsReallyMatter is apparently far too stupid to comprehend.
FactsReallyMatter
1.8 / 5 (10) Feb 14, 2017
...it is the massively higher RATE of atmospheric release here that is the problem with man made sources compared to that of natural sources. ...


Based on what evidence? The temp data and CO2 levels are not correlated. The models don't make worthwhile predictions. All we have is your faith that man-made CO2 will terminate the earth. That may work for you, but most people live in a rationale world. That is why most people find your fear-mongering entertaining, but not persuading.
Anonym
3 / 5 (6) Feb 14, 2017
@hurny: please offer a link to that study. I'd like to know the methodology that determined global volcanic CO2 emissions. Could it be that the number you have comes from a modelled guesstimate?

There are known unknowns (like volcanic CO2 emissions) and there are suspected unknowns.

This article is among the first I've seen that hints at this particular suspected unknown -- that CO2 seeps from the ground all over the globe, more some places than others, but all over the globe because it is produced by microorganisms in the crust. Since this source has not yet been quantified, it is impossible to know how much of the deadly pollutant that threatens to devastate all life on Earth is supplied by the Earth itself: The point is that there must be yet undiscovered "carbon" sinks recycling these unaccounted emissions. These undiscovered mechanisms, once quantified, will likely show that the IPCC guesstimate way overestimates CO2 persistence.
antialias_physorg
4 / 5 (8) Feb 14, 2017
"For example, releasing only 1% of this CO2 into the atmosphere will be the equivalent of burning 2.3 trillion barrels of oil.

Seems like a pretty pointless statement. The 1% figure is completely arbitrary.

If carbon "350km beneath the Earth's surface" is in danger of being released sequestration at shallow depths looks like fail.
Yes, it means this carbon reservoir is huge, but no: it should not suggest that 1% -or even 0.001%- of this stuff is in danger of leaking out any time soon. We're talking geologiocal timescales and an equilibrium cycle, here. Not a net expulsion into the atmosphere.
katesisco
3 / 5 (2) Feb 14, 2017
My guess is that in the deep past we have seen substantial solar energy emissions---flares if you like---that heat ALL the core bodies orbiting around Sol, and will while we wont be here to see the future flares, they will occur.
Yes, the strange arrangement of our surface minerals allows the NA mineral body to override the Pacific body and trap this huge carbon amount.
I read Dr W Brown's book In The Beginning accidently and discovered it was not a creationist theory but a geologic one hiding until science proved the underlying concepts.
humy
3 / 5 (2) Feb 15, 2017
@hurny: please offer a link to that study. I'd like to know the methodology that determined global volcanic CO2 emissions..

Anonym

Which "study" are your referring to? I didn't mention any particular one study as my info comes from continually studying science for the last ~45 years.
If you want to know the methodology that determined global volcanic CO2 emissions, don't be so stupidly lazy; just google it yourself and learn it. It is all well established well researched well documented science.

ChrisTH
not rated yet Feb 27, 2017
Is it realle "melting carbon" (3550 C) or melting CARBONATES (850 C) - there is a difference, you know ?
And if it is Carbonates (what i suspect), it is long not said that they must release CO2 - only at extensive heat or contact to acid. The bigger danger i.m.h.o. is that these are alkaline and would cause tremendous pH imbalances on the surface. Btw i dont believe the myth of the "climate change by CO2" - people claiming this have a chemistry background similar to the writer of this article.

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