He is a highly respected geologist and geophysicist. His specialty is the study of rocks that contain traces of the earth's ancient magnetic field. His work has resulted in many important contributions, including helping to reconstruct the motions of the continents and adding to our knowledge about Canada's physical origins. He also helped to create global databases on paleomagnetism and developed field and laboratory procedures that have become the standard worldwide. A fellow of both the Royal Society of London and of Canada, he has been widely recognized for his profound influence on the earth sciences.