The towns of Oil Springs and nearby Petrolia supplied 90% of Canada's oil needs before 1900, and the oil drilling technology developed in these fields was used world-wide.
(the oil drilling technology; developed; L:in these fields) (The towns of Oil Springs and nearby Petrolia supplied 90% of Canada's oil needs before 1900, and the oil drilling technology; was used; L:world-wide)
the oil drilling technology The towns of Oil Springs and nearby Petrolia supplied 90% of Canada's oil needs before 1900, and the oil drilling technology
developed was used
L:in these fields
L:world-wide