The answer may be that what is happening is not geochemical at all, but biochemical.
See also geochemical facies.
Organic chemical reactions influence many geochemical processes, as, for example, rock weathering and production of soil, the solution, precipitation, and secretion of such dissolved materials as calcium carbonate, and the alteration of sediments to form sedimentary rocks.
During Galileo's flybys of Earth and the Moon in December 1990 and 1992 en route to Jupiter, the spacecraft demonstrated the potential for spaceborne multispectral observations i.e., imaging the Moon in several discrete wavelength ranges to gather geochemical data.
1990 Galileo spacecraft collects compositional remote-sensing data during lunar flyby, demonstrating potential for future orbital geochemical missions.
The radioactive elements tend to be preferentially driven off from these rocks for geochemical reasons.
The mineralogy, petrology, geochemistry, and geochronology of lunar rocks were studied in detail, and this research made it possible to work out the geochemical evolution of the Moon.
The concept of a geochemical cycle encompasses geochemical differentiation (i.e., the natural separation and concentration of elements by Earth processes) and heat-assisted, elemental recombination processes.
Much about the environments dinosaurs lived in can be learned from studying the pollen and plant remains preserved with them and from geochemical isotopes that indicate temperature and precipitation levels.
Since the late 20th century the development of advanced technologies for dating rocks, together with geochemical techniques and other analytical tools, have revolutionized the understanding of early Earth system history.
