In a typical oil and gas reservoir only a fraction of the resource is actually recovered. The vast majority remains locked underground. To increase oil and gas yields from wells, companies inject carbon dioxide or water into the reservoir. This approach, known as enhanced oil recovery, could help meet the global demand for fossil fuel while reducing the need to drill new wells. Enhanced oil recovery can also be used to sequester carbon dioxide emissions underground. At Stanford, several researchers in the School of Earth Sciences are focused on improving the mechanistic understanding of enhanced recovery processes.