Olivine—The Alteration Rock Star

Olivine is the main component of the Earth’s upper mantle, on which our tectonic plates rest. As such, olivine has been studied since the dawn of geology and is regarded as the storyteller of the Earth’s interior. Its physical and chemical properties provide insight into its creation in magmas and its voyage through the upper mantle. However, when olivine is exposed to aqueous fluids, it adopts a more rebellious, rock star–like disposition. Here, we show that the discord, or disequilibrium, between olivine, its reaction products, and fluids containing water and carbon dioxide is so significant that it has been instrumental in changing the Earth throughout the planet’s history and will continue to do so well into the future.