Kinetics of mineral dissolution

The rates of mineral dissolution contribute to processes controlling soil fertility, porosity in aquifers and oil reservoirs, transport and sequestration of contaminants and CO₂, cycling of metals and formation of ore deposits, and many other geochemical characteristics and phenomena. For example, the weathering rates of Ca- and Mg-silicates influence the concentrations of CO₂ in the atmosphere over 10⁵-10⁶ y timescales, impacting the global carbon cycle. Mineral dissolution thus influences the chemical and physical nature of our landscape as well as the quality and quantity of potable water and fertile soil available to sustain ecosystems. The rates of mineral dissolution (Fig. 5.1) determine the lifetimes of minerals in soil environments. Especially since the 1970s, researchers have focused on measurement of mineral dissolution rates in order to promote quantitative prediction of the evolution of our environment (Stumm, 1997). In this chapter, we discuss many of the concepts and models used to predict mineral dissolution rates for oxide, carbonate, and silicate minerals.