Early record of tectonic magnetic fabric during inversion of a sedimentary basin Short review and examples from the Corbières transfer zone (France)

An integrated study combining anisotropy of magnetic susceptibility (magnetic fabric) and analysis of meso-scale structures is presented. The studied sites, which belong to the Corbières transfer zone (France), suffered a clear polyphase deformation. The magnetic fabric is of tectonic origin and records an early layer parallel shortening. In general, this primary fabric is not altered by later deformations including folding. However, secondary fabrics have been observed in the vicinity of major faults. They are probably related to tectonically driven fluids migrating along these planes. Consequences on interpretation and use of magnetic fabrics in inverted sedimentary basins are discussed.