Marine sediments record variations in the Earth's magnetic field
Monday, November 28, 2016 - 09:01
in Earth & Climate
Past variations in the strength of the Earth's magnetic field are reflected by the production of isotopes in the atmosphere. Researchers from the CNRS, Aix Marseille Université and the French Alternative Energies and Atomic Energy Commission CEA have used an isotope extracted from marine sediments to identify such geomagnetic excursions over a particularly long period. Beryllium-10 provides a timeline stretching back over the past 850,000 years, during which its concentration fluctuated according to the strength of Earth's magnetic field. The work, published in Journal of Geophysical Research: Solid Earth, provides a new tool to study past variations in the Earth's magnetic field and its behavior in the future.