New experiments suggest that molten iron could lay permanent channels within the mantle. 
Photos from open sources Our planet has a complex interior, it has many layers. The formation and structure of these layers is the secret behind seven seals, but from time to time clues appear – thanks to new studies, of course, not prayers. Iron settled on the bottom of the ocean of magma, and then seeped through the solid mantle to the core. (Image of the authors of the work.) If we commit journey to the center of the earth, then we will see that most of the material on a depth of up to 3 thousand km is composed of only three elements: oxygen, silicon and magnesium (plus some iron) account for more than 90% “ceramic” mantle of the Earth. Our mantle serves as a wonderful electro and thermal insulation. We go deeper – and everything changes. We cross the boundary of the stony mantle with a metal core, which is on the upper plots is a liquid, and in the very center of the planet becomes hard. The chemical composition is also different: almost the entire core composed of iron. According to physical characteristics, the outer core of the Earth just as different from the mantle as the sea from the bottom. Imagine an inverted world in which storms and currents are not above, but under a layer of rock. It is such flows of red-hot metal in the core Earth generates its magnetic field, which protects us from solar storms and makes life possible on the surface of the planet. how so it happened that so different layers were next? A group of scientists led by Wendy Mao from Stanford University (USA) was able to show how iron is displaced from silicates on a depth of about 1,000 km. Laboratory experiments with mixtures silicate minerals and iron indicate that iron is in rock in the form of tiny isolated formations being locked trapped at the junctions between grains of minerals. This is observation led scientists to conclude that iron segregation occurs only in the early stages of planet formation when the upper part the silicate mantle is completely molten. Believed to be drops iron seeped through the upper mantle and collected in it base, and then under the influence of gravity, as in a lava lamp, sank further, and so in the end the nucleus formed. Work Ms. Mao requires a revision of this model. Using intense X-ray radiation researchers studied samples, under extreme pressure and temperature between tips of diamond crystals. It turned out that with increasing pressure in the interior of the mantle, liquid iron begins to wet the surface of grains of silicate minerals. This means that threads molten iron is collected in streams in a solid mantle – this the process is called percolation. More importantly, this process may occur even when the mantle is not hot enough to the formation of the ocean of magma. “For percolation to be effective, molten iron must be laid continuous channels through firmament, explains Ms. Mao. – It was considered impossible, but now we say that under certain conditions, which, as we know, existed on the planet, this could happen. ” results, Jeffrey Bromily of the University of Edinburgh (UK) notes: “New evidence suggests that core formation was not a simple, single-stage event. And this one a complex process must have had an equally complex impact on subsequent Earth chemistry. “Ms. Mao’s work raises important questions about how the formation of the core of the planets begins. Generally accepted theory says that studying the nuclei of meteorites and asteroids will tell us about our own planet, but Mr. Bromily believes that the earliest core formation is only possible on large planets. therefore Earth’s chemical composition has changed a lot in this process and now significantly different from the composition of smaller planets and asteroids. Mr Bromili and his colleagues today find out what other factors could affect the formation of the earth – for example, collisions with asteroids and other bodies in the chaos of the early solar system. Them conclusions also add questions. “We are increasingly seeing metal nuclei of bodies are much smaller than the Earth, – explains scientist. – What process affected the formation of nuclei in bodies, which were never so big that there was a place percolation of melts at great depths? “Results studies published in the journal Nature Geoscience.
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