118 | Great Geologists
John Tuzo Wilson
apart again. All of these ideas were
developed when he was in his fifties,
following a remarkable revision of his
views on global tectonic processes.
Wilson was born in Ottawa in 1908. To
his family he was known as Jack, or
Jock, but during his professional career
he began to use his middle name, Tuzo
(his mother’s maiden name) to avoid
confusion with another J.T. Wilson. Whilst
at high school, he obtained summer
employment with the Geological Survey
of Canada, which provided him not only
with his introduction to geology, but also
the skills needed to carry out fieldwork in
wilderness areas.
John Tuzo Wilson in 1992. Photograph by Stephen
Morris.
The eminent biologist Theodosius
Dobzhansky once stated, “Nothing in
biology makes sense except in the light of
evolution”. Almost all geologists working
today would be happy to rephrase this as
“almost nothing in geology makes sense
except in the light of plate tectonics”.
The decade from 1960 to 1970 saw a
revolution in Earth sciences, with the
acceptance of the general tenets of
continental drift, as pioneered by Alfred
Wegener several decades previously, and
their modification into the single, widely
accepted paradigm of plate tectonics. At
the centre of this revolution was one of
the greatest Canadian scientists of the
20th century — John Tuzo Wilson.
Wilson was a dynamic individual who
contributed three key ideas to plate
tectonic theory: mantle hot spots to
explain volcanoes located away from
plate boundaries, transform faults, and
supercontinent cycles in which moving
continents rift, collide and then break
Having developed an interest in science,
he decided to study geology and physics
at the University of Toronto. There was no
degree in geophysics when he enrolled
in 1926, and it was only through special
permission that he became the first
student to graduate from the university
with a joint degree in physics and
geology. Wilson then spent two years
at the University of Cambridge before
returning to North America to undertake a
PhD at Princeton University. This involved
mapping the Beartooth Mountains of
Montana, where he carried out fieldwork
on his own, including the ascent of Mount
Hague, a flat-topped mountain over 3,700
m high. No doubt the geology of this
region inspired an interest in mountain-
building that would ultimately lead to his
contributions to plate tectonic theory.
Wilson joined the Geological Survey of
Canada after his PhD graduation and