According to geophysics, the Earth's magnetic field exists due to the liquid outer core of the Earth. In 2007
Researchers Dave Stegman, Leah Ziegler and NicholasBlank note that scientists believe that the Earth’s mantle is a very poor electrical conductor, so if the lowest layer of the mantle were liquid, the movements inside it would not create such electric currents that are necessary to create a full-fledged magnetic field.
The team of scientists first usedquantum mechanical calculations to predict the conductivity of a silicate fluid - of which the mantle could have composed - under the conditions of the existence of an ocean with basal magma. These calculations showed that this layer of the Earth could be very electrically conductive.
This means that the mantle could create the firstmagnetic protective layer on Earth, scientists say. In addition, such data can be used in the future to study tectonic shifts in the history of the Earth.
In addition, the appearance of a magnetic field precisely from the mantle, and not the nucleus, could lead to the fact that life on Earth appeared earlier than if it would have happened under other scenarios.