Study hints that ancient Earth made its own water—geologically

Study hints that ancient Earth made its own water -- geologically
This plate tectonics diagram from the Byrd Polar and Climate Research Center shows how mantle circulation delivers new rock to the crust via mid-ocean ridges. New research suggests that mantle circulation also delivers water to the oceans.

A new study is helping to answer a longstanding question that has recently moved to the forefront of earth science: Did our planet make its own water through geologic processes, or did water come to us via icy comets from the far reaches of the solar system?

The answer is likely "both," according to researchers at The Ohio State University— and the same amount of that currently fills the Pacific Ocean could be buried deep inside the planet right now.

At the American Geophysical Union (AGU) meeting on Wednesday, Dec. 17, they report the discovery of a previously unknown geochemical pathway by which the Earth can sequester water in its interior for billions of years and still release small amounts to the surface via plate tectonics, feeding our oceans from within.

In trying to understand the formation of the early Earth, some researchers have suggested that the planet was dry and inhospitable to life until icy comets pelted the earth and deposited water on the surface.

Wendy Panero, associate professor of earth sciences at Ohio State, and doctoral student Jeff Pigott are pursuing a different hypothesis: that Earth was formed with entire oceans of water in its interior, and has been continuously supplying water to the surface via plate tectonics ever since.

Researchers have long accepted that the mantle contains some water, but how much water is a mystery. And, if some geological mechanism has been supplying water to the surface all this time, wouldn't the mantle have run out of water by now?

Because there's no way to directly study deep mantle rocks, Panero and Pigott are probing the question with high-pressure physics experiments and computer calculations.

"When we look into the origins of water on Earth, what we're really asking is, why are we so different than all the other planets?" Panero said. "In this solar system, Earth is unique because we have liquid water on the surface. We're also the only planet with active plate tectonics. Maybe this water in the mantle is key to plate tectonics, and that's part of what makes Earth habitable."

Central to the study is the idea that rocks that appear dry to the human eye can actually contain water—in the form of hydrogen atoms trapped inside natural voids and crystal defects. Oxygen is plentiful in minerals, so when a mineral contains some hydrogen, certain chemical reactions can free the hydrogen to bond with the oxygen and make water.

Stray atoms of hydrogen could make up only a tiny fraction of mantle rock, the researchers explained. Given that the mantle is more than 80 percent of the planet's total volume, however, those stray atoms add up to a lot of potential water.

In a lab at Ohio State, the researchers compress different minerals that are common to the mantle and subject them to high pressures and temperatures using a diamond anvil cell—a device that squeezes a tiny sample of material between two diamonds and heats it with a laser—to simulate conditions in the deep Earth. They examine how the minerals' crystal structures change as they are compressed, and use that information to gauge the minerals' relative capacities for storing hydrogen. Then, they extend their experimental results using computer calculations to uncover the geochemical processes that would enable these minerals to rise through the mantle to the surface—a necessary condition for water to escape into the oceans.

In a paper now submitted to a peer-reviewed academic journal, they reported their recent tests of the mineral bridgmanite, a high-pressure form of olivine. While bridgmanite is the most abundant mineral in the lower mantle, they found that it contains too little hydrogen to play an important role in Earth's water supply.

Another research group recently found that ringwoodite, another form of olivine, does contain enough hydrogen to make it a good candidate for deep- water storage. So Panero and Pigott focused their study on the depth where ringwoodite is found—a place 325-500 miles below the surface that researchers call the "transition zone"—as the most likely region that can hold a planet's worth of water. From there, the same convection of mantle rock that produces plate tectonics could carry the water to the surface.

One problem: If all the water in ringwoodite is continually drained to the surface via plate tectonics, how could the planet hold any in reserve?

For the research presented at AGU, Panero and Pigott performed new computer calculations of the geochemistry in the lowest portion of the mantle, some 500 miles deep and more. There, another mineral, garnet, emerged as a likely water-carrier—a go-between that could deliver some of the water from ringwoodite down into the otherwise dry .

If this scenario is accurate, the Earth may today hold half as much water in its depths as is currently flowing in oceans on the surface, Panero said—an amount that would approximately equal the volume of the Pacific Ocean. This water is continuously cycled through the transition zone as a result of plate tectonics.

"One way to look at this research is that we're putting constraints on the amount of water that could be down there," Pigott added.

Panero called the complex relationship between and surface water "one of the great mysteries in the geosciences." But this new study supports researchers' growing suspicion that mantle convection somehow regulates the amount of water in the oceans. It also vastly expands the timeline for Earth's .

"If all of the Earth's water is on the , that gives us one interpretation of the water cycle, where we can think of water cycling from oceans into the atmosphere and into the groundwater over millions of years," she said. "But if circulation is also part of the water cycle, the total cycle time for our planet's water has to be billions of years."


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New evidence for oceans of water deep in the Earth

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Dec 17, 2014
The percentage of total water on earth is .02% of its total mass. Its not a long shot to think that all the water on earth came from the same rocks that accumulated when earth was formed.

Dec 17, 2014
"We're also the only planet with active plate tectonics."

Debunking the myths of Plate Tectonics
http://users.indi...onsense/

Dec 17, 2014
"We're also the only planet with active plate tectonics."

Debunking the myths of Plate Tectonics
http://users.indi...onsense/


Of all the pseudoscience promoted here "the expanding earth" ranks with the worst.

Dec 17, 2014
M Herndon Nuclear Planet
The mineral majorite is intensely oxygenated. Does this suggest water?

Dec 17, 2014
I had to stop reading Solon's site after a while; I was laughing so hard at the sillies, my family began throwing things at me...

One aside-- don't just look at GPS data showing lateral movement, as radio astronomers with ultra- long-baseline, multi-site set-ups do it in the round. They must even account for earth-tides etc. If they didn't, they would get no useful data...

Nice to get such a really clear 'fringe' signal; makes it easy to add perp to blocked list...

Dec 17, 2014
M Herndon Nuclear Planet
The mineral majorite is intensely oxygenated. Does this suggest water?


Herdon's Nuclear Planet has been thoroughly debunked.

yep
Dec 18, 2014
Popcorn expands why can't we.
http://od.pgi.gov...umes.pdf
Models change based on data. Some of you old timers like to cling to the cherished beliefs of your childhood and anything contrary is labeled as pseudoscience, in that regard you are as foolish as the religionist.
Stop right here, and READ the abstract posted above before you are compelled to be an @ss, you might learn something new.
Thanks.

Dec 18, 2014
@yep

Who in the hell reads only the abstract when the entire study is available?

Your link is better than most concerning EE but the author puts his peculiar spin on the data available at the time and most importantly he has no mechanism to drive expansion.

I have more but it's late so I'll be back tomorrow.

Dec 18, 2014
"Earth is the only planet with plate tectonics", it's also the only planet with liquid water on its surface. ----Venus is a tad too warm for liquid water while Mars has lost most of it's magnetic field so solar winds would be able to strip it of any water it had long ago. The other planets are rather cold for liquid water. Seems like the writer was grasping with the statement about plate tectonics and earth being the only one with liquid water. Not saying the theory is wrong, but there's more than one reason no water is on Mercury.

Dec 18, 2014
Earth can't been totally devoid of water, since plate tectonics need it. And it was wet already 4.4 billion years ago [zircon data], so presumably the water was also released by volcanism et cetera at the start. But plate tectonics may explain part of the water, as it now seems from models a huge impactor flow (with mostly small ones) erase more volatiles (atmosphere) than they deposit.

"We're also the only planet with active plate tectonics."

Curiously, it seems that Europe has an ice plate tectonics analog. Presumably it can happen on all bodies with a liquid inner layer, if the crust/ice is not too thick due to near same temps above and below. (E.g. why Venus has none.)

@mikael_spoto: That is the surface water. For 50 or so years the hypothesis was "one ocean belwo for every ocean above". The find of ringwoodite with its water meant that hypothesis was tested earlier this year. So perhaps 0.05 % water by mass, before this claim on the deep water cycle.

Dec 18, 2014
@yep: An analogy isn't equivalence. Rock density is much the same at some pressure independent of temperature, so planet expansion is unlikely. You have hence no mechanism. And in fact we see from e.g. Mars that it didn't happen, so any such hypothesis (with a mechanism) would fail the test.

We know this. I don't know why people like to post ludicrous ideas, but go ahead. Just make it science, this is a science site after all, not a fringe lunatic site. E.g have a mechanism, quantify it so it can be tested, and provide a way to test.

Dec 20, 2014
M Herndon Nuclear Planet
The mineral majorite is intensely oxygenated. Does this suggest water?


think minerals like gypsum CaSO4·2H2O

Dec 21, 2014
Torbjorn_Larsson_OM claimed
Earth can't been totally devoid of water, since plate tectonics need it
Really ? In what context, surely not as a lubricant ;-) ?

U later mention 'ice plate..', so upon reflection re above did u mean only 'ice plate' or not ?

Torbjorn_Larsson_OM offered
"We're also the only planet with active plate tectonics."
Not clear on the detail on why this is the case or is it only based on early limited observation ?

Might be tectonic plates as such on Venus but not as active as on Earth, we do know Venus has more volcanoes than others even Europa etc some 1600 but so far not that active except possibly this:-
http://www.nytime...tml?_r=0

Recall ~15yrs ago Venus TV doco suggested fair rationale; mantle of Venus gradually built up heat via radiation decay then each ~100M yrs depending also on Sun, bulk of crust melted, liberating immense heat, then re-solidified, explains lack of craters etc !

Dec 21, 2014
@ Solon (and Zeph)

This is exciting. It is possible that I'm not even wrong, but my EE/EU/AWT might be what both of you are looking for - Expanding Earth Electric Universe Aether Wave Theory. It's based loosely on a solid conjecture of unified vacuous-plasma-mechanics.

My mind is frothing with impending feckless analogies, but it is apparent that the expansion of the sun will dwindle from excessive electric plasma emissions, allowing the ever-expanding earth to consume it in several billienia.

Ripples of aether-wave induced cold fusion from overly-enlarged continental masses could energize planetary-sized subduction zones and, as you can well imagine, a sad farewell to the planets that lose out in the process. (subduction of Pluto will be like chewing on ice)

Details slow in coming due to a HAARP-addled condition compounded by recent chemtrails. Awaiting next orgone burst of quantum healing energy.

Should work.

Maladroitly yours,
F.P.

Dec 21, 2014
Wow, Frilla. Just - wow...
I can almost smell the hallucinogens in your breakfast cereal....
Altho, It might be that your comment was a rather droll attempt at satire...

Dec 21, 2014
Ahem. Excuse my insolence. I merely espoused a potpourri of the intolerable fringe. It was beyond reason. No reason. No reason good reason whatsoever.

Unless possibly a contemptibly poor effort to attaining higher ranking in an esteemed index:
http://math.ucr.e...pot.html
http://en.wikiped...ot_index

It was the "expanding earth" reference in the second comment that truly moved me. Then followed the entirely justified:

Of all the pseudoscience promoted here "the expanding earth" ranks with the worst.

Sorry Vietvet. My bad. My record of comments here is lamentable. In atonement I bestow fives unto thee.

(Please note: My comments are no worse than the pseudoscience, overly theistic, abject denialist, etc. posts I have to read)

Dec 21, 2014
Ahem. Excuse my insolence. I merely espoused a potpourri of the intolerable fringe. It was beyond reason. No reason. No reason good reason whatsoever.

Unless possibly a contemptibly poor effort to attaining higher ranking in an esteemed index:
http://math.ucr.e...pot.html

It was the "expanding earth" reference in the second comment that truly moved me. Then followed the entirely justified:

Of all the pseudoscience promoted here "the expanding earth" ranks with the worst.

Sorry Vietvet. My bad. My record of comments here is lamentable. In atonement I bestow fives unto thee.

(Please note: My comments are no worse than the pseudoscience, overly theistic, abject denialist, etc. posts I have to read)

Satire it was, then.... Kudos...

Dec 22, 2014
@Frilla_Poo
LOVED IT - it also sounds like you would like to join our new group!
A 501(c)3 non-profit with religious connotations i am calling
"Aged science and the Wisdom of our Eastern-Western ancestors extra scientific healing ministry of scientific Satanic Witchcraft and new Pagan-Christo-Muslim-Judaism Science with scientific extra terrestrial wisdom of the hidden science of the Government area 51 science and conspiracy of deviant Sex science medicine"
Notice the extra science in it, so that it must be true, as well as the inclusion of ancient, both hemispheres, alien as well as scientific and modern beliefs from Wicca to sexual deviance. This is being suppressed by the government because of the high secrecy classification i had in the military, so you will not find ANY writings of this at all,except what i have secretly stolen from the government when i was stationed at Area 51

the gov't will deny this, of course
trust me, i am a trained professional

Dec 22, 2014
@Mike Massen: "In what context, surely not as a lubricant ;-) ?"

Exactly as a lubricant, but more essentially here: plate tectonics need a certain viscosity in the subducting plates, and water that are pulled down with subducting oceanic crust makes the rocks more pliable as they melt.

It also helps remelt the rocks, though some believes that is not a 100 % effective process. (I.e. there could be crust remains piling up next to the core, predicting the seismic anomalies in that zone.)

"why this is the case".

We have extensive observations of other terrestrial planets and moons, specifically the crater record that enables precise relative dating. (Even for Venus and Titan due to radar observations.)

In no case do fresh surfaces like among Earth's plates show up, except for Europa and some moons that have other tectonic changes. (Think Io. Enceladus is a special case due to the plume snow next to the vents...)

[tbctd]

Dec 22, 2014
[ctd]

Venus may or may not have had an early crust turnover, before it got too thick.

The thickness buildup wasn't due to inner heat of course (less mass than Earth's) but due to the greenhouse runaway - roughly the same heat on both sides means shutting down convection and hence crustal growth.

[Please excuse my lack of references, I have little time for that today.]

Dec 22, 2014
There are likely to be yet other minerals that contain water, that are stable only under high pressure and temperature. There will still be much similar work to perform to find them.

Dec 22, 2014
Cap'n.
I managed to locate and abscond a very informative Wiccan guide to area 51 and it's devious goings on... It also mentions Hollywood in an almost reverential tone
Quite enlightening and explains a great deal (you should see the chapter on EU -TWO of them, in fact). A good thing I am well versed in both the Sciences and the Arts, so as not to be subtly swayed to the dark side by the succubine essence of it all...
BTQ, did you know that Yahwe is actually a reference to "Bill and Ted's Excellent Adventure"? Seems a time traveler used it numerous times when talking to some of the early Israelites. and somehow it stuck... (They were quite impressed with film early on, it is suspected...)

Dec 23, 2014
Captain
We should start crowdfunding for a device to read the messages left in the anally probed alien abductees. Surely the aliens have left important messages in there, maybe it's where they store their bible and they are probing abductees to spread the word.

Dec 26, 2014
Elsewhere Water_Prophet claimed
How can you say I ignore longwave radiations?
By evidence U ignored long wave (LW) radiation re CO2's interference to space, U only saw TSI.

U write fossil fuel (FF) proportion of TSI, yet U IGNORE FACT Earth converts short wave (SW) to LW & CO2 interferes with emission to Space. Nobody is disagreeing FF adds heat & CO2. But, U, as a claimed Physical Chemist (PC) haven't acknowledged CO2's interference U even claimed "CO2 is a red herring", which is obviously completely WRONG !

Water_Prophet claimed
..1998 was a very hot year; Industry was booming and the Sun was at/near a max
Huh? U claim Sun TSI was at max ? Not according to this
http://www.skepti...asic.gif

Water_Prophet claimed to be a PC, yet doesn't write like one, does Water_Prophet accept:-

1. TSI mainly SW
2. Earth converts SW to LW
3. LW to space interfered by CO2

Simple issue Water_Prophet I asked before, WHY do u evade ?

Feb 17, 2015
Torbjorn_Larsson_OM suggested
Exactly as a lubricant, but more essentially here: plate tectonics need a certain viscosity in the subducting plates, and water that are pulled down with subducting oceanic crust makes the rocks more pliable as they melt
But surely it cannot be free water, it is held as hydrates within the crystal structure ?

And if iirc many hdrated minerals are more brittle & less plastic due to H2O in the crystal structure adding discontinuities ?

Torbjorn_Larsson_OM claimed
It also helps remelt the rocks, though some believes that is not a 100 % effective process
Are you suggesting there is a relationship between hydrated minerals and their change in structure offering a form of hysteresis in temperature for a "remelt" comparatively other than an initial 'melt' - that is following a hydration ?

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