The core of earth which is in semi-solid state has been mixing with other layers as per a new study which discovered that innermost part of the earth has been leaking into mantle plumes that slowly reach surface of the earth. This discovery has helped to settle a long debate if core of the earth interfaces with the mantle say the researchers who published details of their study in “The Conversation. They showed evidence of earth’s innermost layers transfer to base of earth’s mantle plumes for part 2.5 billion years.
This discovery was made due to presence of tungsten metal which is made up of iron and nickel. If the dating profile of tungsten were to be taken it would be a siderophile and it also has few isotopes. During their study researchers decided that these isotopes would help them sort out the earth’s core leaking question. They studied another element called hafnium which is a lithophile or an element that loves rocks and is generally found in mantle region of the earth’s core that is rich in silicate. Its half-life is of 8.9 million years and its radioactive isotope is hf-182 decays into 182.
Scientists reasoned that this is why earth’s mantle should have more of W-182 than the core but the difference in tungsten could be very small. It is not easy to study earth’s core as it begins at a level of 1800 miles underground. The closest humans have gone to earth’s core has been at Kola Superdeep Borehole in Russia which is at a depth of just 7.6 miles. To keep their study active researchers then studied rocks that were close to the mantle at Pilbara Craton, Reunion Island and Kerguelen Archipelago. The amount of tungsten on rocks in these areas revealed leak from earth’s core and change in 182W/184W ratio of earth’s mantle shows that tungsten from core has been leaking into mangle for several years.