Nanopaleomagnetism

Bish

Magnetic map (right) of micrometer-scale area of Bishunpur chondrite obtained using scanning magnetic tunnel junction (MTJ) microscopy. Red (blue) indicates positive (negative) values for the vertical component of the stray field. The dark patches in the optical image (left) are dusty olivines, while the bright spots are metal (Fe) grains.

NanoPaleoMagnetism at the University of Cambridge

Geologic materials are heterogeneous in terms of composition, texture, and alteration state. As with any physical and chemical properties, natural magnetic remanence recorded in rocks and minerals is susceptible to alteration and decay over time. The more complex the geological history of a rock is, the more likely it is for it to have experienced conditions that overprinted or erased its original magnetic information. This renders bulk magnetic measurements useless in the case of very old and altered terrestrial, and especially extraterrestrial, materials. At the University of Cambridge I am part of a team that seeks to overcome these issues by developing a multi-scale approach to rock magnetism and paleomagnetism, which adopts recent technological developments in solid-state physics and materials science.

Papers

Channell, J. E. T., Harrison, R. J., Lascu, I., McCave, I. N., Hibbert, F. D. and Austin, W. E. N., 2016, Magnetic record of deglaciation using FORC-PCA, sortable-silt grain size, and magnetic excursion at 26 ka, from the Rockall Trough (NE Atlantic), Geochemistry Geophysics Geosystems 17, p. 18231841, doi: 10.1002/2016GC006300

Lascu, I., Harrison, R. J., Li, Y. T., Muraszko, J. R., Channell, J. E. T., Piotrowsky, A. M. and Hodell, D. A., 2015, Magnetic unmixing of first-order reversal curve diagrams using principal component analysis, Geochemistry, Geophysics, Geosystems 16, p. 2900-2915, doi:10.1002/2015GC005909.

Harrison, R. J. and Lascu, I., 2014, FORCulator: A micromagnetic tool for simulating first-order reversal curve diagrams, Geochemistry, Geophysics, Geosystems 15, p. 4671-4691, doi:10.1002/2014GC005582.

Software

FORCem

FORCulator