For many years it has been thought that chemical and isotopic equilibrium are often reached in high-temperature settings. Higher temperatures tend to increase chemical exchange rates and should thus facilitate the attainment of equilibrium between substances. However, attainment of equilibrium is difficult when a system is large or is undergoing changing conditions (e.g. during cooling). The snapshot of the path towards equilibrium presents itself as disequilibrium chemical and isotopic signatures in minerals and rocks. These signatures allow geochemists to probe the timescales and mechanisms of natural processes in systems that are otherwise inaccessible to direct observation.

We invite contributions from researchers working on theoretical, natural, and experimental kinetic isotope effects in high-temperature (hydrothermal, metamorphic, igneous) systems. Contributions on quantifying isotopic equilibrium are also welcomed, as they serve as a necessary baseline from which disequilibrium can be identified.

• GS: Geochemical Society -