Oil companies are not about to bring on new refining capacity. Oil companies are investing their research dollars looking for the replacement for oil. No one knows yet, but the alternatives are all too expensive to be currently viable alternatives. Having to search in more remote locations increases the cost of the oil that you finally find. Finding a bunch of small fields causes the cost of oil to be higher than one large field.
Remote locations increase the cost to get the oil.
The older an oilwell gets, the more expensive it is to get the oil out of the ground. Various factors determine the exact lifespan of an oilwell, but in general, the oil that comes out of the ground in the early years is the least expensive to produce and the oil at the end is the most expensive. So expensive that many oil companies would rather cap a well than try to get the bottom oil. It is actually counter productive to push OPEC to increase production. They are just pumping more and more of the expensive oil.