Martha Kosters, Utrecht University, Utrecht, Netherlands, Annemarieke Béguin, Utrecht University, Paleomagnetic laboratory Fort Hoofddijk, Utrecht, Netherlands, Roger R Fu, MIT-EAP Sciences, Cambridge, MA, United States, Karl Fabian, Geological Survey of Norway, Trondheim, Norway, Auke Barnhoorn, Delft University of Technology, Delft, Netherlands and Lennart V. de Groot, Utrecht University, Geoscience, Utrecht, Netherlands