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Biogenic magnetic minerals are abundant in sediments and are highly sensitive indicators of past environmental conditions and climates, as well as the behaviour of the geomagnetic field and the geodynamo. Since magnetic properties are easy and fast to measure, they have therefore been proposed as a palaeoenvironmental proxy. Key to using sedimentary magnetism as a palaeoenvironmental proxy is the correct identification and characterization of biogenic magnetic minerals, amongst them so-called magnetosomes produced by magnetotactic bacteria (MTB), purely from magnetic measurements.

My research aims to do this through numerical micromagnetic models that allow to simulate the magnetic response of different morphologies and mineralogies of MTB. To date, this includes forward modelling of various MTB, and correlation of magnetic signals of MTB to microscopic imaging. Current and future research focusses on the effect that mechanical compression (compaction) of sediments has on magnetosome and other magnetic mineral morphology, such as chain collapse of magnetosomes. Understanding the effect of e.g. magnetosome chain collapse will not only help to improve the use of MTB as a palaeoenvironmental proxy, but will also allow to better understand magnetic remanence signals in sedimentary records. The latter is essential for use in magnetostratigraphic dating of sediments, for reconstruction of relative magnetic palaeointensities giving insight into the geodynamo, as well as for discriminating between depositional and post-depositional remanences and other re-magnetizations.