The geodynamo is the mechanism by which the Earth’s magnetic field is generated through the motion of conductive materials in the Earth’s outer core. The geodynamo is crucial in understanding geomagnetism, the behavior of the Earth’s magnetic field over geological time, and its implications for plate tectonics and life on Earth.
Source Glatzmaier, G. A., & Roberts, P. H. (1995). A Three-Dimensional Self-Consistent Computer Simulation of a Geodynamo. Nature.