A recent study published in Geology reveals that an extinct offshore volcano near Portugal has the capacity to store between 1.2 and 8.6 gigatons of carbon dioxide, equivalent to 24-125 years of the nation’s industrial emissions. This approach employs ‘in situ mineral carbonation,’ where CO2 reacts with specific rock elements to form stable minerals, offering a quick and efficient method for underground carbon storage. The researchers targeted the Fontanelas volcano due to its suitable structure and rock composition, which are ideal for facilitating these reactions.
This method shows potential advantages over traditional carbon capture techniques, as volcanic basalt can mineralize carbon dioxide rapidly—up to 95% in just two years, as demonstrated in Iceland—reducing concerns over gas leakage. The study utilized seismic data from previous oil explorations and analyses of dredged samples indicating successful natural carbonation, confirming that the necessary chemical processes for carbon storage are already occurring. This research suggests that, beyond Fontanelas, similar offshore volcanic sites worldwide could also serve as effective carbon sequestration solutions, contributing to global decarbonization efforts.
