Quantitative rock magnetism

Using principal component analysis to discriminate between magnetic end members (EMs) in geologic materials. An example of quantifying multi-domain (EM1), pseudo single-domain (EM2) and single-domain (EM3) constituents from North Atlantic sediments (Lascu et al., 2015).

The majority of natural samples contain a complex, multi-component mixture of different magnetic phases with a wide range of particle sizes derived from a variety of possible sources. Quantifying the contribution of these phases in rocks and sediments is thus a fundamental task in all paleomagnetic and environmental magnetic studies. Consequently, developing methods to “unmix” magnetic end members in natural samples continues to be one of my chief research foci. I have developed methods that are applicable to both bulk magnetic measurements, which are used by a wide range of scientists, as well as advanced rock magnetic techniques that yield precise quantitative determinations of magnetic domain state contributions with the aid of multivariate statistics.


Lascu, I., Einsle J. F., Ball, M., Harrison, R. J., 2018, The Vortex State in Geologic Materials: A Micromagnetic Perspective, Journal of Geophysical Research: Solid Earth 123, 7285–7304, doi:10.1029/2018JB015909.

Lascu, I., Banerjee, S. K. and Berquó, T. S., 2010, Quantifying the concentration of ferrimagnetic particles in sediments using rock-magnetic methods, Geochemistry, Geophysics, Geosystems 11, Q08Z19, doi:10.1029/2010GC003182.

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., Muraszko, J. R., Heslop, D., Lascu, I., Muxworthy, A. R., Roberts, A. P., 2018, An improved algorithm for unmixing first-order reversal curve diagrams using principal component analysis, Geochemistry Geophysics Geosystems 19, 1595–1610, doi: 10.1002/2018GC007511.

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.

Myre, J. M., Lascu, I., Lima, E. A., Feinberg, J. M., Saar, M. O. and Weiss, B. P., Using TNT-NN to unlock the fast full spatial inversion of large scanning magnetic microscopy datasets, Earth, Planets and Space, in review.

Jackson, M. J., Bowles, J., Lascu, I. and Solheid, P., 2010, Deconvolution of u-channel magnetometer data: Experimental study of accuracy, resolution and stability of different inversion methods, Geochemistry, Geophysics, Geosystems 11, Q07Y10, doi:10.1029/2009GC002991.