The Earth's magnetic field is produced by electrical currents due to chemically-driven convection in the liquid outer core. It is well known that the geomagnetic field creates a protective shield (the magnetosphere) around our planet, which protects life from the cosmic radiation and retains the Earth's atmosphere. It is well established now, that for the last few hundreds of million years, the field has a dipole configuration which allows us to use rock magnetizations to decipher tectonic plate motions, reconstruct ancient supercontinents, and resolve many other geological and geophysical problems.

However, very little is known about the magnetic field of the young Earth. When and why did the Earth's magnetic field start? What was its configuration? How stable was it? Did it affect early biological evolution? Answering these and other similar questions represent one of the frontiers of modern Earth Science. In my talk, I will present recent experimental and theoretical advances in understanding of the magnetic field of the early Earth and their implications for the study of the early evolution of our planet.