Next100 - A Dialogue on the Next Century of Energy

Jul 15 2008

Study: Undersea Rocks Might Store Carbon Dioxide

Deep ocean-floor drilling and experiments show that volcanic rocks off the West Coast and elsewhere might be used to store huge amounts of global-warming carbon dioxide captured from electric power plants and other sources, a group of scientists at Columbia University says. Chemical reactions under 30,000 square miles of ocean floor off California, Oregon, Washington and British Columbia could lock in as much as 150 years of carbon dioxide production from the U.S., the scientists say. Their findings are published today in the Proceedings of the National Academy of Sciences.

Interest in storing the greenhouse gas is growing but no large-scale projects have emerged and other geological settings could be problematic. The oil industry has been pumping carbon dioxide into spaces left by old oil wells on a small scale, but some fear that these might eventually leak, sending the gas back into the air and possibly endangering people.

Lead author David Goldberg, a geophysicist at Columbia's Lamont-Doherty Earth Observatory, said the study is "the first good evidence that this kind of carbon burial is feasible."

"We are convinced that the sub-ocean floor is a significant part of the solution to the global climate problem," Goldberg said. "Basalt reservoirs are understudied. They are immense, accessible and well-sealed -- a huge prize in the search for viable options." A main advantage is a chemical process that takes place between basalt and pumped-in liquid carbon dioxide that would form a solid, nontoxic mineral. Basalt rock is formed by solidified lava.

Skeptics, however, point out that getting the carbon dioxide to undersea sites could be expensive and tricky. But Goldberg says the West Coast formations should be close enough to land for delivery by pipelines or tankers.

Posted by: Leonard Anderson | Comments (0) Permalink