John Tuzo Wilson, primarily known as Tuzo Wilson, was born on October 24, 1908 in Ottawa, Ontario. While in high school Wilson gained some of his first geologic exposure from gaining summer employment through the Geological Survey of Canada. He then continued his interests at the University of Toronto. In 1930 he received his B.A. in physics and geology, the first such person to receive this degree from the University. In 1936 he then graduated from Princeton University with his doctorate in geology. After finishing his academic studies, Tuzo enlisted in Canadian Army and served during World War II. In 1946 he then became Professor of Geophysics at the University of Toronto, and was later appointed principal of the University's Erindale College in 1967. In 1974 Wilson was named Director General of the Ontario Science Centre. He was also the chancellor of York University (1983-1986). John Tuzo Wilson died on April 15, 1993 in Toronto, Ontario.
Specific contributions to plate tectonic theory
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.
Other interesting scientific contributions
-During the 1960's Wilson also spent a great deal of time looking at the North Atlantic Ocean. He showed that there was strong evidence for an earlier Atlantic ocean that was closed by continental drift and then reopened, along a slightly different center, into our current Atlantic. His detailed work lead to the categorization of the world's oceans in terms of the stages of development in a cycle that is now called the Wilson Cycle.
-Wilson helped pioneer the use of air photos in geological mapping. He was responsible for the first glacial map of Canada.
Further cool stuff you should know
-Due to his great contributions to geology and geophysics, mountains in Antarctica (Mt. Wilson Click the zoom out button a few times for the imageto appear) and an extinct volcano on the floor of the Pacific, off Canada's west coast, (Tuzo Wilson Seamounts) are named in his honor.
-Tuzo Wilson was the first non-American president of the American Geophysical Union (1980-82), which altered its rules to allow his election
-Tuzo Wilson was highly interested in Chinese culture, so much that he had a junk (Chinese water craft) built and imported to Toronto. He can be seen at the helm during the television series 'Planet Earth'. He also assisted in the production of the series.
Science.ca (n. d.) John Tuzo Wilson. Retrieved February 9, 2009, from http://www.science.ca/scientists/scientistprofile.php?pID=232
University of Toronto (n. d.). John Tuzo Wilson. Retrieved February 6, 2009, from http://www.physics.utoronto.ca/overview/history/john-tuzo-wilson
The Trustees of Columbia University in the City of New York, Lamont-Doherty Earth Observatory (2004). The Vetlesen Prize. Retrieved February 9, 2009