Yes, of course it will. As supply drops, prices rise. It's not cost-effective to make gasoline from tar sands at $100 / barrel, but it would be very cost-effective at $1,000 / barrel (and substantially less).
The thing is, that applies to more than just petroleum reserves.
At some point, it becomes cost-effective to create syngas as a feedstock for petroleum distilleries, and to create that syngas with atmospheric CO2 for the carbon source using solar photovoltaics as the energy source. And, yes, oil would have to be very expensive for that to be cost-effective.
Before it's cost-effective to use atmospheric CO2 for the carbon source, it'll be cost-effective to use CO2 captured from coal plant exhaust. We'd still burn the coal for electricity generation, but the carbon would serve double duty and get burned twice before being dumped in the atmosphere. Still very expensive, yes, and still needs lots of photovoltaic electricity as input, but it's not quite as expensive as pulling the CO2 directly from the atmosphere.
Thing is...the price at which these sorts of non-petrochemical alternatives become cost-effective is less than the price at which many petrochemical alternatives become cost-effective to exploit.
So I personally doubt we'll ever touch the Canadian tar sands. They're too expensive, and we have cheaper alternatives that are inexhaustible.
That's not to say that the alternatives are affordable, just that they're less expensive than the tar sands.
Whether or not we can afford any of the alternatives remains to be seen. Of course, the other alternative is a retreat from civilization, so let's hope that we actually do figure out a way to pay for all of this....