Paleomagnetism

Paleomagnetism is the study of the terrestrial magnetic field recorded by rocks at the time of their formation or during relevant geological processes that took place afterwards (e.g. metamorphism). It is based on this three basic assumptions: 1) Axial geocentric dipole: The terrestrial magnetic field is similar to that produced by a geocentric dipole that is parallel to the rotational axis of the Earth (at least the mean over a specific period of time). Therefore, the paleomagnetic poles calculated within a specific area will coincide with those of the rotational axis. 2) Record of the primary magnetic field: The ferromagnetic minerals contained in rocks can record the past terrestrial magnetic field. 3) Unchanged record over time: The magnetization acquired by a rock at the time of its formation may remain unchanged over time. The laboratory deals mainly with magnetic stratigraphy issues (reverse polarity), rock magnetism and anisotropy of magnetic susceptibility in various sedimentary environments.