Andrea Biedermann: Characterizing Anisotropy of Ferromagnetic Grains: Methods and Challenges
Channel: Institute for Rock Magnetism
Date: 2021-06-02

12th Institute for Rock Magnetism Conference

Session 1: Anisotropy and Applications
Conveners: France Lagroix (IPGP) and Suzanne McEnroe (NTNU)

Title: Characterizing Anisotropy of Ferromagnetic Grains: Methods and Challenges

Author: Andrea R. Biedermann

Institution:
Institute of Geological Sciences, University of Bern, Switzerland

Abstract:
Magnetic anisotropy is a powerful proxy for the preferred alignment of minerals in deformed rocks, and has important consequences for the interpretation of paleomagnetic directions and paleointensities. In both areas, an accurate description of the anisotropic properties of relevant grains is crucial. This applies especially in complex rocks containing multiple minerals or grain populations, and having experienced several deformation events. Numerous methods exist to measure bulk magnetic fabrics, separate different sub-fabrics, or isolate the fabric carried by a specific sub-population of grains. This presentation focuses on characterizing the anisotropy of ferromagnetic grains, and gives an overview of the methods, comparing the grains or minerals targeted, addressing advantages and challenges of each technique, and recent advancements in anisotropy characterization and interpretation. The presentation will also cover examples of how a detailed understanding of anisotropy and its sources can advance the interpretation of structural and paleomagnetic data.