Researchers at the University of Southampton have identified regions where igneous rocks can store huge quantities of industrial CO2 just beneath the Earth's crust.
Led by postgraduate researcher Chiara Marieni, they identified five potential offshore regions in Australia, Japan, Siberia, South Africa and Bermuda, ranging in size from a half million square kilometres to nearly four million square kilometers.
"We have found regions that have the potential to store decades to hundreds of years of industrial carbon dioxide emissions although the largest regions are far off shore," Marieni said.
CO2 turns into a liquid at high pressure and low temperatures, and as it would be heavier than water, researchers say the liquid CO2 would be easy to store in the ocean's upper crust.
The locations suggested by the researchers are fractured rocks with large spaces, and may over time react with the CO2 to turn into solid calcium carbonate, permanently preventing its escape from the ocean.