Late quaternary high frequency geomagnetic field dynamics

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The long-term objectives of this research program are twofold: scientific and methodological. At the scientific level, the long-term goal is to reconstruct centennial to millennial changes in Earth's magnetic field direction and intensity during the Late Quaternary in order to determine the high frequency dynamics of the geomagnetic field with a special emphasis on abrupt changes. The recent recovery of several high resolution (>1 m/ka) sediment cores from Eastern Canada and the Western Canadian Arctic along with the planned recovery of sediment cores from the Northwest Passage and Eastern Canadian Arctic will allow the first large-scale study of geomagnetic field dynamics in the Arctic, as well as the determination of the spatial extent of abrupt geomagnetic field changes. Another long-term scientific goal is to determine the influence of Earth's magnetic field morphology on the production rate of cosmogenic isotopes. At the methodological level, the long-term goal is to develop paleomagnetic regional master curves (inclination, declination and paleointensity) for Eastern and Arctic Canada, allowing the dating and synchronization of Late Quaternary terrestrial, lacustrine, marine and possibly ice core records. In addition, because the magnetic properties of the sediments measured for paleomagnetic purposes depend on the mineralogy, grain size and concentration of the magnetic grains, I also envision combining magnetic and physical property data to develop a rapid, non-destructive and high resolution original method to identify lithological variations associated with paleoclimatic or environmental changes in Eastern and Arctic Canada.