What makes up the middle of the Earth? Nobody truly knows the chemical composition of the planet's interior because it is impossible to go down beyond ten kilometers into the mantle of the Earth. Scientists often get their information from volcanic rocks that have formed by the melting of the chemicals in the planet's interior.
A team of geochemists from the University of Amsterdam and the University of Munster have conducted an investigation of the build up of volcanic rocks in Portuguese island group of Azores. Their main goal was to gather more information, new and more relevant, about the compositional evolution of the materials found at the Earth's mantle. These cover the layers that are roughly composed of 30 up to 2,900 kilometers deep into the Earth.
Through the use of sophisticated analytical equipment and technology, the team uncovered that the composition of the mantle below the Azores is significantly different from what was expected. The study suggests that a huge part of the area is composed of elements that have been considered incompatible. These chemical elements have come together as a result of the constant melting of the materials in the mantle, accumulated in the crust of the Earth.
In the study, the researchers were able to come to a conclusion that over the course of the Earth's history, a large amount of the materials in the mantle of the Earth have melted, which ultimately became part of the Earth's crust. "To be able to sustain the materials needed by both the crust and the mantle, a mass flux between the interior and the surface of the Earth must have gone through the process at a relatively higher rate," said Prof. Andreas Stracke, a professor from the Munster University and lead author of the study.
As the materials from the mantle of the Earth in the area in the Azores, which are unexpectedly similar to the materials on the crust, researchers could only conclude that the materials that make up the Earth's mantle might not be the same as what people think there is.
"The results of the study have indeed opened new doors for new perspective to surface," said Andreas Stracke. "The goal of the study is to open more doors to find out the composition of the Earth. After all, the mantle part of the Earth accounts for over 80% of the Earth's volume. The results of the study have been published in the Nature Geoscience journal.
The researchers presume that this new information about the geochemical data will be able to help address the global deficit of materials from the Earth's mantle. Continuing research with their working hypothesis will mean the collection of samples from other volcanic islands across continents.
