Physorg: Estimates of how much crude oil we have extracted from the planet vary wildly. Now, UK researchers have published a new estimate in the International Journal of Oil, Gas and Coal Technology that suggests we may have used more than we think. The idea that we are running out of oil is not a new one, but do we even know how much oil we have extracted from since the first commercial oil wells were sunk in the middle of the nineteenth century? In 2008, chemists Istvan Lakatos and Julianna …