University of Cambridge found that with a slow collision of tectonic plates of the Earth’s subsoil in subduction zones, more carbon is absorbed than previously thought. The results of the study will help develop new ways to save the planet from the climate catastrophe due to the growth of carbon dioxide concentration. This is reported in the article published in the journal Nature Communications.
Researchers found out that only a third of carbon, which circulates under volcanic chains, returns back to the surface of the planet. It was previously believed that the flows balance each other, and everything that falls into the mantle returns back. Carbon enters the mantle in the form of carbon-containing compounds (for example, in the composition of shells and other organic residues) through subduction, when some blocks of the earth’s crust are immersed under the other. Part of this amount is then thrown through volcanoes.
It turned out that chemical processes in the rocks occur in the mantle in rocks and send it deeper into the bowels of the earth, preventing his return to the surface. This showed the results of experiments in the European Union of Synchrotron Radiation. To simulate pressure and temperature in the depths of the Earth, scientists took advantage of the diamond anvil, in which a sample of carbon-containing rocks was placed. Carbonate rocks become less rich in calcium and richer magnesium, when penetrating deeper into the mantle. As a result, the carbonate decreases solubility, and it does not fall into the liquid medium under the active volcanoes. Carbon is immersed deeper into the mantle, where it can turn into a diamond.
According to scientists, their research shows that carbonate rocks effectively absorb carbon and can store it for a long time. Currently, a group of researchers is exploring the possibility of using similar methods to capture carbon from the atmosphere to rocks and oceans, which may be useful to combat the concentration of greenhouse gases.