Storing carbon dioxide below the Earth's surface could be a safe, long-term solution to one of the planet's major contributors to climate change. University of Leeds research shows that porous sandstone, drained of oil, could provide a safe reservoir for carbon dioxide. The study found that sandstone reacts with injected fluids more quickly than had been predicted, which is necessary to stabilize and store the CO2.
The study looked at data from the Miller oilfield in the North Sea, where seawater was being pumped into the oil reservoir to enhance oil flow. As oil was extracted, the water that was pumped out with it showed that minerals had grown and dissolved in it. Ph.D. student Stephanie Houston found that the water was especially rich in silica. Silicates, usually thought of as slow to react, had dissolved in the seawater within a year.
Leeds' Professor Bruce Yardley explained that, "If CO2 is injected underground we hope that it will react with the water and minerals there in order to be stabilized. That way it spreads into its local environment rather than remaining as a giant gas bubble, which might ultimately seep to the surface." The technique has long-term potential for storing carbon dioxide, rather than allowing it to escape and further contribute to global warming. There is one storage project in place at Sleipner, in the Norwegian sector of the North Sea.