Dan Peter McKenzie is a Professor of Geophysics at the University of Cambridge, and one-time head of the Bullard Laboratories of the Cambridge Department of Earth Sciences. He wrote the first paper defining the principles of plate tectonics, and his early work on mantle convection created the modern discussion of planetary interiors.He received Copley Medal in 2011 for his seminal contributions to the understanding of geological and geophysical phenomena including tectonic plates.