I won't be entirely accurate in my calculations as the data is difficult to accurately measure, I can give a rough estimate though. It is estimated that we have pumped out 2.5 trillion barrels of oil, and we've used about half that much. One barrel is about 42 gallons of oil, so that equals about 105 trillion gallons of oil, pumped out and 52.5 trillion gallons of oil used. Lake Superior alone holds about 3 quadrillion gallons of water. Lake Ontario holds about 400 trillion gallons of water. So all the oil ever pumped out of the Earth would fill up about one quarter of Lake Ontario, and about 3/100th of Lake Superior.
Since the Earth is constantly generating new oil, and there are probably many oil wells that have yet to be discovered it is unknown just how much oil is left in the Earth to be pumped.
