John H. Hodgson
John H. Hodgson (Sept. 24 1913 - Jan. 8 2011) was a seismologist, a Fellow of the Royal Society of Canada, head of the Dominion Observatory in Ottawa, and later chief seismologist of a UNESCO seismological project.
One of his three children is the singer-songwriter Sneezy Waters, and his father, Ernest Hodgson, was also a prominent seismologist.
He held degrees in Applied Mathematics and in Geophysics.
He worked in industry from 1936 to 1944. He then became Assistant Professor at the University of Toronto for several years, then held various positions as a seismologist or manager with the Dominion Observatory and Canadian federal government from 1949 to 1973, and was Chief Seismologist with a UNESCO project from 1973 to 1979.
Hodgson was seismic chief when in 1958, seismograph inventor Patrick Willmore proposed an extensive seismograph network for Canada, with stations every 500 miles. Hodgson encouraged Willmore to go ahead with the idea but didn't think the budget for it would be approved; however, it was approved by Cabinet. 
Hodgson attempted to apply worldwide a method which had previously been developed by others, in order to look for patterns in focal mechanisms of earthquakes to provide insights into plate tectonics. With the data available at the time it didn't produce much in the way of results, but later when a more extensive worldwide seismograph network was in operation, it was found that Hodgson's methodology did produce significant information which helped with the development of plate tectonics. 
- Deaths, Globe and Mail, Jan. 14, 2011
- New Scientist No. 220, Feb. 2, 1961, p. 268, Mapping the Earth Below the Surface by John Lear http://books.google.ca/books?id=jzXythBBc64C&pg=PA268&lpg=PA268&dq=john+hodgson+earthquake&source=bl&ots=eI_H1cJlJr&sig=ACEe3JrswlDpNGSYSwa-FJwPAk4&hl=en&ei=Wss9TcK3EIGqsAOHj5GBAw&sa=X&oi=book_result&ct=result&resnum=9&ved=0CEYQ6AEwCA#v=onepage&q=john%20hodgson%20earthquake&f=false