It isn't reasonable to think that oil will suddenly become unavailable leading to an abrupt price spike. Instead, the cost to extract the oil will increase over

It isn't reasonable to think that oil will suddenly become unavailable leading to an abrupt price spike. Instead, the cost to extract the oil will increase over time causing the market to adjust via lower demand or substitute products. The 'invisible hand of the market' will have no problem in directing a transition. The recent increase in oil production due to fracking and horizontal drilling is a perfect example of the market directing investment in response to an increase in price.