John Tuzo Wilson, Canadian geologist and geophysicist (d. 1993)
John Tuzo Wilson (October 24, 1908 – April 15, 1993) was a Canadian geophysicist and geologist who achieved worldwide acclaim for his contributions to the theory of plate tectonics.
Plate tectonics is the scientific theory that the rigid outer layers of the Earth (crust and part of the upper mantle), the lithosphere, is broken up into around 13 pieces or "plates" that move independently over the weaker asthenosphere. Wilson maintained that the Hawaiian Islands were created as a tectonic plate (extending across much of the Pacific Ocean) shifted to the northwest over a fixed hotspot, spawning a long series of volcanoes. He also conceived of the transform fault, a major plate boundary where two plates move past each other horizontally (e.g., the San Andreas Fault).
His name was given to two young Canadian submarine volcanoes called the Tuzo Wilson Seamounts. The Wilson cycle of seabed expansion and contraction (associated with the Supercontinent cycle) bears his name.