Arthur Holmes was the originator of the concept that convection currents in the mantle drove continental drift.

A major criticism of Wegener’s continental drift theory, and one that Wegener was well aware of, was that he was not able to convincingly describe a mechanism that caused continental drift. A missing piece to this theory was delivered in 1927 by British geologist Arthur Holmes (1890–1965) who argued that radioactive decay of elements in the Earth would generate convection currents that could drive continental drift. The decay of naturally occurring materials like uranium and thorium would provide the heat necessary to power convection. Holmes’ idea, however, was ignored for over thirty years, and it was not until the theory of seafloor spreading that his concept of “mantle currents” gained wide acceptance.