Portuguese scientists have discovered that the extinct volcano Fontanelas, off the coast of the Iberian Peninsula, could absorb between 1.2 and 8.6 billion tons of carbon dioxide. This is equivalent to the country’s industrial emissions over 24 to 125 years. It can be used to remove greenhouse gases from the atmosphere and fight global warming. This is reported in an article published in the journal Geology.
Scientists suggest that the capture and storage of carbon in coastal underwater volcanoes can be an effective way to remove much more greenhouse gases from the Earth’s atmosphere. International efforts have removed about 42.6 million tons of carbon dioxide from the atmosphere, according to the Global CCS Institute.
Storage of carbon dioxide depends on a process called mineral carbonization. When carbon dioxide reacts with the chemical components of certain types of rocks, new minerals are formed that include carbon dioxide. For example, magnesium, calcium, and iron form dolomite, calcite, and magnesite, respectively. Thus, rocks containing these elements are ideal candidates for this process. These include, for example, volcanic basalts on the seafloor.
Most carbon capture projects are based on injecting carbon dioxide into closed pools of porous sedimentary rocks. In this case, minerals that reliably bind carbon begin to form decades or even centuries later. In 2016, data were published on the higher performance of basalts, which formed carbon-bearing minerals in as little as two years. In addition to the rate of fixation, storage reliability is also an advantage, since the likelihood of carbon dioxide leakage is very low.
Scientists have estimated the carbon storage capacity of the partially buried Fontanelas volcano, which was formed during the Cretaceous period. It is about 100 kilometers from the coast of Lisbon, and its top is located about 1,500 meters below sea level. The authors analyzed data obtained during oil exploration in the area of the shelf. The recovered samples contained natural carbonate minerals indicating the potential feasibility of carbonization. The study demonstrates that ancient volcanoes on the continental margins are suitable sites for safe carbon storage with a total storage capacity of hundreds of gigatons of CO2.
This discovery could be a breakthrough in the fight against global warming and help reduce carbon dioxide levels in the Earth’s atmosphere. In addition, it could become a new area of research on underwater volcanoes and their role in the planet’s ecosystem.