Scientists have determined the exact size of the central part of the Earth’s inner core. It is reported by TASS with reference to a publication in Nature Communications.
The earth consists of three main layers – the crust, the basalt mantle and the metallic core. Each of these elements is also divided into layers, in particular, they distinguish a liquid outer core and a solid inner one. It will remain solid due to the enormous pressure, despite the high temperature, and at the same time rotates relative to other layers. In 2015, scientists discovered that the inner core is also divided into several layers with different properties.
Hrvoe Tkalcic of the Australian National University and his colleagues analyzed seismic vibrations that passed through the entire thickness of the Earth and for the first time received accurate data on the structure of the inner core. To do this, they analyzed all the most powerful underground vibrations that have been recorded by seismic stations around the world since 2010, and selected from them those that were noted in opposite parts of the world at about the same time. This allowed scientists to identify almost 200 sets of seismic waves that passed several times through the entire thickness of the Earth, including through its core.
The analysis confirmed that the inner layer of the solid part of the Earth’s core really exists, and also indicated that the size of this part of the core was greatly underestimated. According to the calculations of professors Tkalchich and Thanhson Pham, the radius of the isolated central part of the core is about 650 kilometers, which is twice the previous estimates.
In addition to this, scientists have identified differences in the density and structure of the central and outer layers – the latter turned out to be much more “loose” and less ordered than the core of the inner core. This is probably due to the peculiarities of the cooling of the bowels of the planet in the past.
Earlier, geologists announced the discovery of silicon “snow” at the core-mantle interface.