The final puzzle piece in the jigsaw of the Earth’s core was discovered by scientists to complete the image of the contents, regarding elements, of the Earth’s core. The experiments and findings were by scientists from the University of Tohoku, according to the World Economic Forum.
The innermost part of the Earth, or the ‘core’, is made almost entirely of iron at 17 parts in 20. It is 1 part in 10 nickel. However, the remaining 5% – the remaining 1 part in 20 – appears to have been, for some time, a mystery. Based on research by Japanese team, the missing element has been discovered, which is now known to be silicon.
The BBC has reported on this. The solid core of the Earth lies about 3,000 kilometres below the surface with a radius of 1,200 kilometres, or a diameter of 2,400 kilometres (2r=d). It is deep, so deep as to almost be impossible to make direct tests about it.
The deepest mines in the world reach to only about four kilometres. Many of these mines are for gold mining. Many researchers thought that the element must be lighter because of the easy bonding of the metals, which might explain the properties of the mystery element while at the time not knowing its precise label.
So there was a minor model, a miniature model, of the Earth composed of a crust, mantle, outer core, and inner core. Alloys were made from iron and nickel and silicon with the admixture. They put them under tremendous pressure and temperatures upwards of 6,000°C.
The conditions in the experiment matched those from seismic data gathered about the Earth’s core. That seismic data is based on waves that appear to have emanated from the Earth’s core. The team then use this to extrapolate for sufficient evidence – and from the experiment – as to the contents of the core of the Earth as silicon, which was then claimed to be the missing element of the core of the Earth.
The Japanese team presented their research in the Fall meeting in San Francisco of the American Geophysical Union.
Simon Redfern, professor of mineral physics at the University of Cambridge, said:
These difficult experiments are really exciting because they can provide a window into what Earth’s interior was like soon after it first formed, 4.5 billion years ago, when the core first started to separate from the rocky parts of Earth…But other workers have recently suggested that oxygen might also be important in the core.