1University of Bristol, Bristol, BS8 1TH UK
2National High Magnetic Field Lab and Earth, Ocean and Atmospheric Sciences, Florida State University, Tallahassee, FL 32306 USA
3German Research Centre for Geosciences GFZ, 14473 Potsdam, Germany
4Memorial University, St. John’s, NF A1B 3X9 Canada
5University of Leeds, Leeds, LS6 1AN UK
6GEOMAR, 24148 Kiel, Germany
7University of California, Riverside, CA 94720 USA
8Simon Fraser University, Burnaby, BC 8888 Canada
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