Centre Européen
de Recherche et d'Enseignement
des Géosciences de l'Environnement

Earth's magnetic field

Our research interests are spatial and secular variations of the Earth's magnetic field. Palaeomagnetism and archaeomagnetism (intensity and directions) of lava flows and archaeological samples are studied. Since these data are not homogeneously distributed at the Earth's surface, we developed in the last decade an innovative techniques of coupling between isotopic geochemistry (10Be) and palaeomagnetism on sedimentary core samples. This allows to, after calibration and extrapolation, reach a unique high-resolution (<1000 years) record witnessing fast variations of the geodynamo (inversions, excursions). Recently, we extended our expertise by comparing those signals to 10Be and 36Cl measurements on polar ice, as well as to 14C measurements on tree circles in order to reach decadal data.

Another research topic of this axis concerns the crustal magnetization. Numerical modeling of magnetized geological sources is performed beneath the largest magnetic field anomalies (Bangui, West Africa). This modeling is well-constrained by rock magnetism measurements on samples and by studying the pressure effect on the deep magnetization.