Geochemistry

Definition

The science of the chemical composition, chemical processes, and chemical evolution of the Earth.

The Earth consists of chemical elements that mainly formed before the existence of the Earth. During the formation and evolution of the planet and subsequent geological history, these have become redistributed and, in the case of radioactive elements, have transmuted into other elements. Initially, redistribution depended wholly on inorganic processes, but once living organisms appeared, they played an increasing part in geochemical processes on land and in surface- and groundwater. In recent times, human activities have increasingly affected processes in the shallow Earth’s Crust, water, and the atmosphere. Therefore, geochemistry was initially focused on the geological past but has become increasingly important in respect of geological resources and environment protection. The theoretical basis of geochemistry is physical and chemical laws governing the behavior of...