For more than 50 long years scientists have remained perplexed as to why iron down in the innermost core of Earth behaves the way it does. Now a research has shown that iron, which is the main constituent of the core of Earth, can become unusually soft at extreme temperature and pressure.
This research can substitute the age old ways of studying earthquakes and in the nearest future we can expect materials that can handle the force of an earthquake in a way better than what all we have seen till now.
The research was carried out by a team of Swedish and Russian researchers who used advanced computer simulations that were performed on supercomputers. The research has also provided an answer for seismic data-signals that our Earth transmits during an earthquake. These have been captured by stations all over the world and the variations of these signals till now have remained an enigma for researchers.
Anatoly Belonoshko at the Royal Institute of Technology in Stockholm directed the studies. He stated that:
“These new discoveries about the innermost part of the earth provide an explanation for the low velocity of the seismic waves deep down in the earth. They explain, in turn, why signals from earth tremors look like they do, thereby facilitating the work of seismologists.”
Researchers also stated that the innermost core of the earth consists of highly compressed iron in a solid state, but due to the high pressure and temperature there is loses all its rigidity and starts to behave more like a liquid. It lacks all the resistance to shear enabling the shifts to take place easily inside the core of earth. This is the reason for the seismic waves to move slowly than expected on the surface of the inner core.
The pressure and the temperature inside the core of the earth is extremely high, these extremes make iron behave like a liquid, which was not expected by scientists, because iron has never shown such tendencies to change its basic properties in experiments conducted in laboratories.
To explain these dual state characteristics of iron, the researchers stated that atoms of iron are so arranged that they can move under extremes as present in the inner part of earth. It behaves more like a solid structure held together with rubber bands.
A more technical answer to this riddle is that iron at the centre of the earth is not present in a form like it is present on the surface of earth. The iron we all know is a single crystalline form of iron, whereas, when we go deep inside the core of earth then we find iron which is more like a polycrystalline material with liquid-like granule edges and masses of defects in the structure. These characteristics of iron inside the core of the earth make it to behave more like a liquid.
The next milestone for researchers is to develop new ways to calculate the elastic properties of various materials at high temperatures.
Via: Sciencedaily
Comments
It is bout natural that at such an extreme temperature , Iron behaves as a liquid .
Most of the people must be taking it as a very simple concept coz obviously the core of earth has a very high that measure approx. 5000-6000 °C. but logically, it’s not extremely high temperature that decides the state of iron (coz iron melts at 1535 ºC) but the high pressure that ranges from 330-360 GPa that renders it hard even in such a high temp. so the new finding really makes me think that how iron manages to remain liquid under such extreme conditions?