David Gubbins is Research Professor of Earth Sciences in the School of Earth & Environment, University of Leeds, UK. He did his PhD on geomagnetic dynamos in Cambridge, supervised by Sir Edward Bullard (qv.) and has worked in the USA and in Cambridge before moving to Leeds in 1989. His work has included dynamo theory and its connection with the Earth's thermal history, modelling the Earth's magnetic field from historical measurements, and recently the interpretation of paleomagnetic data. He is a Fellow of the Royal Society and has been awarded the Gold Medal of the Royal Astronomical Society and the John Adam Fleming (qv.) Medal of the American Geophysical Union for original research and leadership in geomagnetism.

Emilio Herrero-Bervera is Research Professor of Geophysics at the School of Ocean Earth Science and Technology (SOEST) within the Hawaii Institute of Geophysics and Planetology (HIGP) of the University of Hawaii at Manoa, where he is the head of the Paleomagnetics and Petrofabrics Laboratory. During his career he has published over 90 papers in professional journals including Nature, JGR, EPSL, JVGR. He has worked in such diverse fields as volcanology, sedimentology, plate tectonics and has done field work on 5 continents