I will take it for granted that your number of 45,000 (let's include geologist, geophysicist and other technical experts in with your engineers) engineering positions. According to Alberta employment in 2014 the upstream oil and gas employed directly almost 140,000. So let's be generous and say that 1/3 of those jobs are technical. The numbers are not that high but for argument sake lets leave there. That still puts 2/3 of employment squarely in non-technical roles. That does not include construction workers pipe fitters, welders or other indirect associated employment.  There is no question that oil and gas employs a tremendous number of highly educated professionals but the total number is small compared to the entire labour force. If current trends persist with automation and the conversion of the digital oil field. This business will continue to employ fewer and fewer people. There is already talk of driverless trucks coming to the oilsands and walking rigs.