Fonds

John Johnston O'Neill was born in Port Colborne, Ontario, on November 12, 1886. He was the son of Irish immigrant Thomas John O'Neill and Mary Jane Henderson, of Marshville, Ontario. He received his elementary and secondary education in Port Colborne and Welland and obtained degrees in geology and mining from McGill University in 1909 and 1910. He earned a PhD in structural geology and petrography from Yale University in 1912 and then did postdoctoral work at the University of Wisconsin in 1912-1913.

From 1909 to 1913, he worked in the field as a student and assistant to the Geological Survey of Canada. He was then hired as a geologist on the Canadian Arctic Expedition (CAE) of 1913, which was organized by anthropologist Vilhjalmur Stefansson. O'Neill was assigned to the expedition's south group, under the leadership of zoologist R. M. Anderson. He subsequently worked for the Geological Survey from 1914 to 1920, exploring copper deposits in the Canadian Far North, among other things. His report on the geology of Canada's Arctic coast was published in 1924.

In 1920 he resigned from the Geological Survey and went to work for Whitehall Petroleum Co., in India, for a year. He returned to Canada in 1921 to take up the position of Assistant Professor of Geology at McGill University. In 1929 he became Head of the Department of Geology and then Dean of Science in 1935. After serving as Dean of Graduate Studies and then Dean of Engineering, he finished his career as Vice-Principal of McGill from 1949 to 1952, when he retired.

In parallel with his McGill career, especially in the 1920s, O'Neill also worked as a consulting geologist to a number of companies, including White Beaver Oil (1921-1922), Pend Oreille Mines and Metals Co. (1928-1930) and Tiblemont Island Mining Co. (1935-1936). He also studied the geology of the Cape Breton coal mines in 1923 and 1924. O'Neill published a huge number of articles in academic journals and newsletters.

Outside of his work, O'Neill chaired the board of the Arctic Institute of North America in 1949, and served as chairman of the Royal Society of Canada in 1950-1951. He was also a freemason and a political Conservative.

He married Lillian May in Ottawa on December 9, 1918. The couple had two children, Gordon Campbell and Melville Henderson. O'Neill lived in Westmount for many years, but later moved to Ottawa, where he died in 1966. In 1999 a new mineral from Mount St. Hilaire was given the name "Oneillite" to underscore his contribution to the study of Canadian geology.