A lithium-isotope perspective on the evolution of carbon and silicon cycles

Abstract

The evolution of the global carbon and silicon cycles is thought to have contributed to the long-term stability of Earth’s climate1–3. Many questions remain, however, regarding the feedback mechanisms at play, and there are limited quantitative constraints on the sources and sinks of these elements in Earth’s surface environments4–12. Here we argue that the lithium-isotope record can be used to track the processes controlling the long-term carbon and silicon cycles. By analysing more than 600 shallow-water marine carbonate samples from more than 100 stratigraphic units, we construct a new carbonate-based lithium-isotope record spanning the past 3 billion years. The data suggest an increase i..