Si stable isotopes in the Earth's surface: A review

Abstract Silicon (Si) is the second most abundant element on Earth after oxygen. Only few studies have attempted to use stable isotopes of Si as proxies for understanding the Si cycle and its variations in the past. By using three different methods (IRMS, MC–ICP–MS and SIMS), the overall measurements show that the isotopic composition (δ30Si) of terrestrial samples ranges from − 5.7‰ to + 3.4‰. Dissolved Si in rivers and seawater is 30Si-enriched (− 0.8‰