Global Ca Cycles: Coupling of Continental and Oceanic Processes

Calcium is one of the most important mobile metals that can migrate easily between major geochemical reservoirs at the Earth's surface; the hydrosphere and the biosphere and crust. In doing so calcium plays a key role in regulating climate over million year time-scales, transferring carbon from the atmosphere and storing it as calcium carbonate. Calcium isotopes potentially provide a way of tracing the mobility of calcium within the Earth surface environment. This chapter reviews the steps where calcium isotopes are fractionated in the weathering and ocean environments, and how these fractionations can be used to constrain mass transfers on both the continents and in the oceans.