Newly discovered iron minerals could be the missing link in how water is stored in the deepest parts of Earth’s mantle and transported to the upper layers, recent research reveals
The findings are crucial for understanding the mantle’s motion, volcanic activity and the workings of other rocky planets, the study authors say.
The researchers discovered the iron minerals, called iron oxyhydroxides, by squishing mineral samples between two tiny diamond anvils while zapping them with a laser.
The two iron minerals are stable at the conditions found at the boundary between Earth’s core and its mantle (the planet’s middle layer), which is under “more than a million times the pressure we feel at the surface,” Steve Jacobsen, a mineralogist and professor of Earth science at the University of Colorado Boulder who was not involved in the study, told Live Science in an email.
The new minerals contain as much as 15 percent water by weight. “If you add up all the H and O atoms in the formula and combine them into H2O, just a five-pound piece of the stuff would contain a pint of liquid water,” Jacobsen added. “If this material existed in the early Earth, spread out across the base of the mantle, even just a few percent of it would potentially be enough to supply the formation of the oceans.”
A tectonic mystery
Earth contains multiple layers, like an onion. The crust is the thinnest layer (the onion skin), and it moves around very slowly on top of a giant ocean of molten rock called the mantle (the juicy part of the onion).
Deep in the heart of that ocean is the planet’s core, made of superheated iron and nickel.
Water in the mantle makes the molten rock stretchier, which means the mantle can change its shape and convect. That’s a big part of why Earth has plate tectonics — without water in the mantle, the material is too stiff to move around and drag the planet’s crust with it.
We know there’s water in the mantle; however, we don’t know exactly what the water in the mantle is doing, and there are two main theories for how water gets into Earth’s mantle.
The first is through subduction: When one tectonic plate sinks under another, it brings water from the surface into the mantle.
The second is primordial water, left over from the planet’s formation, that’s stored near the boundary between Earth’s core and the lower mantle.
The newly discovered minerals match both major theories for how Earth got its mantle water. They’re dense enough to sink all the way to the bottom of the mantle, which fits with subduction and provides a way for water to enter Earth’s core.
The iron minerals are also strong enough to withstand the extremely high-energy impacts that they would have experienced if they were present while Earth was forming.
The mantle’s convection could bring these minerals from near the core to close to the surface in large mantle plumes, where the minerals would melt and release their water, thus completing the water cycle in the mantle and contributing to volcanic hotspots at the surface.
This process has implications for water cycles and theories of how other rocky planets and exoplanets — especially the weird ones that are mostly molten rock — formed.
Although the study, published Sept. 8 in the journal Nature Geoscience, doesn’t prove that these minerals are taxiing water around the mantle, knowing that the iron minerals exist provides a pathway for the first time.
The newly discovered minerals might also explain mysterious, extremely dense regions deep inside Earth —the “ultra-low seismic velocity patches we see sitting on top of the core-mantle boundary,” Jacobsen added.
We know that N. America and Europe are getting farther apart each year. However, N. America and Asia are NOT getting closer every year. How can that be? Well, even NASA admits that Earth is expanding, getting bigger, every year. We see the same thing on other of our rocky planets and moons. The first fallout from this is that there is no subduction. If there was, there would be mountains of ocean muck piling up at all of these zones. Instead, we see rifts and tears in the bottom of oceans.
So, where does the oxygen for the water come from? It might from the same source as the hydrogen and carbon from the breakdown of neutron-rich elements in the core.
[This is the source of the abiotic gas and oil that percolates up from the core to under the lithosphere. Russian scientists were trying for years to get us to see that the isotopes of carbon were all wrong to be from fossils and near the surface. Now, we know that anywhere you drill deep enough you are very likely to find gas and/or oil.]
The water is more likely formed from hydrogen in the core breakdown products percolating upward into the mantle and combining with oxygen in the molten mantle material, water being made “in situ” as it were.
Likely, the Earth formed a complete lithospheric layer as it cooled after formation of the planet. The breakdown of neutron-rich elements made smaller daughter atoms that take up more space than the larger parent atoms.
[Remember, gravity is very weak relative to the electromagnetic force, which is a billion, billion, billion, billion (10^36) times stronger. Electron repulsion by electron shells of these smaller atoms wins over gravity and the material expands.
Over time, expansion pressure in the planet increased until something had to give. First there were massive eruptions, such as the Siberian Traps, lasting maybe 2 million years and kilometers thick (no magma chamber could hold that much material)—a clear release of pressure. However, the cooling lava eventually sealed off these vents and pressure started building again. Then, about 250 million years ago, the lithosphere fractured and the continents began to pull apart. [It is interesting that the Siberian Trap eruptions ceased about the time of the breakup of the lithosphere.] Earth found a new way to release pressure.
Huge, deep rifts appeared and the shallow ocean of the world (there was little, if any, land and thus no land animals) filled them as they grew. This is why we cannot find ocean floor that is older than 250 million years. In addition, this is why the continents fit perfectly together if brought back together on a much smaller planet. Fossil evidence shows that the edges of different continents were once together and this was also the wholesale advent of land animals, as now there was a lot of land, with the water drained away into the growing rifts/oceans.
As the planet expanded, the surface became less curved. The lithospheric pieces would end up as huge over-curved pieces if they did not collapse. Thus, there was a long series of mountain ranges formed as the curved pieces collapsed to conform to a flatter, less-curved world. This is also why fossils from the ancient shallow ocean are found in the mountains as the ocean bottoms in some areas were crushed upward into mountains. The Appalachians formed first and the Rockies later as this flattening continued. Of course, mountain-building will tend to decrease in rate as the surface becomes less and less curved.
So, has anyone estimated how much water is erupted to the surface each year. Maybe, at this point, it is enough to feed the expanding planet and keep the oceans at the same general level, ignoring the sea level changes of the Ice Age changes, of course. Too much water, we end up with less land, and too little, we end up with more land. We shall see.
Crackpot
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But a spring rose out the earth, watering all the surface of the earth.
Genesis 2:6
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Charles Higley
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We know that N. America and Europe are getting farther apart each year. However, N. America and Asia are NOT getting closer every year. How can that be? Well, even NASA admits that Earth is expanding, getting bigger, every year. We see the same thing on other of our rocky planets and moons. The first fallout from this is that there is no subduction. If there was, there would be mountains of ocean muck piling up at all of these zones. Instead, we see rifts and tears in the bottom of oceans.
So, where does the oxygen for the water come from? It might from the same source as the hydrogen and carbon from the breakdown of neutron-rich elements in the core.
[This is the source of the abiotic gas and oil that percolates up from the core to under the lithosphere. Russian scientists were trying for years to get us to see that the isotopes of carbon were all wrong to be from fossils and near the surface. Now, we know that anywhere you drill deep enough you are very likely to find gas and/or oil.]
The water is more likely formed from hydrogen in the core breakdown products percolating upward into the mantle and combining with oxygen in the molten mantle material, water being made “in situ” as it were.
Likely, the Earth formed a complete lithospheric layer as it cooled after formation of the planet. The breakdown of neutron-rich elements made smaller daughter atoms that take up more space than the larger parent atoms.
[Remember, gravity is very weak relative to the electromagnetic force, which is a billion, billion, billion, billion (10^36) times stronger. Electron repulsion by electron shells of these smaller atoms wins over gravity and the material expands.
Over time, expansion pressure in the planet increased until something had to give. First there were massive eruptions, such as the Siberian Traps, lasting maybe 2 million years and kilometers thick (no magma chamber could hold that much material)—a clear release of pressure. However, the cooling lava eventually sealed off these vents and pressure started building again. Then, about 250 million years ago, the lithosphere fractured and the continents began to pull apart. [It is interesting that the Siberian Trap eruptions ceased about the time of the breakup of the lithosphere.] Earth found a new way to release pressure.
Huge, deep rifts appeared and the shallow ocean of the world (there was little, if any, land and thus no land animals) filled them as they grew. This is why we cannot find ocean floor that is older than 250 million years. In addition, this is why the continents fit perfectly together if brought back together on a much smaller planet. Fossil evidence shows that the edges of different continents were once together and this was also the wholesale advent of land animals, as now there was a lot of land, with the water drained away into the growing rifts/oceans.
As the planet expanded, the surface became less curved. The lithospheric pieces would end up as huge over-curved pieces if they did not collapse. Thus, there was a long series of mountain ranges formed as the curved pieces collapsed to conform to a flatter, less-curved world. This is also why fossils from the ancient shallow ocean are found in the mountains as the ocean bottoms in some areas were crushed upward into mountains. The Appalachians formed first and the Rockies later as this flattening continued. Of course, mountain-building will tend to decrease in rate as the surface becomes less and less curved.
So, has anyone estimated how much water is erupted to the surface each year. Maybe, at this point, it is enough to feed the expanding planet and keep the oceans at the same general level, ignoring the sea level changes of the Ice Age changes, of course. Too much water, we end up with less land, and too little, we end up with more land. We shall see.
Reply