Exploratory drilling in Southwestern Ontario increased over 1958, but development drilling decreased. Offshore drilling (exploratory and development combined) increased 39% over 1958. Natural gas production increased by 11% to 17,200,000 MCF. and oil production increased 22.3% to 1,001,600 bbls. This constitutes the highest annual production of petroleum ever taken from Ontario oil fields, including the peak production year in 1894 when 829,000 bbls. were recovered.

Three significant discoveries were made in Southwestern Ontario: one each in Essex, Elgin, and Halton counties.

Tempo of exploration increased noticeably in the Maritimes, where 8 wells totalling nearly 35,000 ft. were drilled. Only 6 wells were completed in Quebec, 5 of these in the St. Lawrence Lowlands, although there was evidence of increased interest in the Gaspe Peninsula. No development wells were drilled and no discoveries were made.