Magnetism and microstructure: from the nanometre to the planetary scale (MICROMAGN)

The importance of mineral magnetism at the nanometre scale has recently been demonstrated in a series of groundbreaking studies, culminating in the development of the theory of ‘lamellar magnetism’. The theory explains how ancient crustal rocks acquire largeamplitude remanent magnetic anomalies that remain stable over billions of years; a problem that has engaged rock magnetists for over 40 years, and continues to engage scientists seeking an explanation for the origin of magnetic anomalies on Mars. The solution to such problems lies in understanding the interaction between chemical and magnetic microstructures at the nanometre scale.

The magnetic properties and behaviour of minerals are profoundly influenced by phase transformations and their resulting microstructures. Nanoscale microstructures are extremely common in magnetic minerals and have a huge impact on their macroscopic magnetic properties. These microstructures not only determine the intensity and stability of macroscopic magnetism recorded in rocks – thereby controlling the fidelity of paleomagnetic recordings at the global scale – but are extremely important in an industrial context, paving the way for the next generation of high-density magnetic recording media. It is now possible to obtain quantitative images of magnetic flux with nanometre spatial resolution. Meanwhile, modern computing power enables us to calculate the interaction between chemical and magnetic ordering in systems large enough to contain heterogeneities at this length scale. It is only now that the dimensions of systems accessible to experimental and computational study have converged, providing the unique opportunity for both communities to work together to solve long-standing problems within the geosciences.

This proposal brings together leading scientists from across Europe with diverse expertise in paleomagnetism, rock magnetism, mineralogy, and solid state physics. It aims to establish quantitative links between the nanoscale microstructure of minerals and their macroscopic magnetic properties, exploiting recent computational and experimental advances that have revolutionised the field.

 

Dr. Richard Harrison (Project Leader)
Department of Earth Sciences, University of Cambridge, Cambridge, United Kingdom

Dr. Rafal Dunin-Borkowski
University of Cambridge, Cambridge, United Kingdom

Professor Ulf Hålenius
Naturhistoriska Riksmuseet, Stockholm, Sweden

Professor Wolfgang Moritz; Dr. Rossitza Pentcheva; Dr. Michael Winklhofer
Ludwig-Maximilians Universität München, München, Germany

Dr. Suzanne McEnroe
Norges Geologiske Undersøkelse, Trondheim, Norway