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The Canadian geophysicist John Tuzo-Wilson was initially sceptical of the theory of Plate Tectonics, but eventually became one of its most famous supporters, proposing two important ideas.

John Tuzo Wilson had two major contributions to the solidification of the theory of plate tectonics, the introduction of hotspots, and the recognition of transform boundaries.

One major argument that some scientists had against the plate tectonic theory in the early 1960's was the existence of volcanically active areas located in the middle of plates instead of near a subduction zone. The lack of explanation was addressed by Wilson in 1963 with his introduction of hotspots. He accepted the idea of sea floor spreading by noticing the increase in age of island rocks with increased distance from the Mid-Ocean Ridge. However, he did find examples of islands that did not fit this trend. He used the Hawaiian islands as an example of this trend bucking phenomenon, this island chain is also volcanically active which was a sticking point for some opponents of the plate tectonic theory. He proposed that the source of volcanic rock for these areas are plumes rising from a 'hot spot' within stable core of a mantle convection cell. As the lithospheric plate moves across a fixed source, older islands of the chain are carried away from the volcanically active hot spot on the moving plate while the current active volcano is located above the plume.

The other large contribution to the plate tectonic theory was the introduction of the idea of a third kind of plate boundary. Up to this point convergent and divergent boundaries were recognized, but these did not account for all types of plate boundaries that were observed on the ocean floor. The perpendicular offsets that are observed along major ocean ridges and are seismically active were well documented. Wilson proposed a new idea that was similar to the current understanding of fault zones in that the medium was conserved but he added that shear motion across a fault joining two ridge segments must end at these segments. These in turn were called transform boundaries.