The various decay products, (sometimes referred to as “progeny” or “daughters”) form a series starting at uranium-238.
Much of the information presented in this section is based upon the Stuiver and Polach (1977) paper "Discussion: Reporting of C14 data". 1890 wood was chosen as the radiocarbon standard because it was growing prior to the fossil fuel effects of the industrial revolution.
Geological processes have helped to create many iconic features on Earth.
Processes, such as plate tectonics, are what shapes the face of the Earth.
In a related article on geologic ages (Ages), we presented a chart with the various geologic eras and their ages.
In a separate article (Radiometric dating), we sketched in some technical detail how these dates are calculated using radiometric dating techniques.
Natural uranium consists of three isotopes: uranium-238, uranium-235, and uranium-234. The nuclei of radioactive elements are unstable, meaning they are transformed into other elements, typically by emitting particles (and sometimes by absorbing particles).
Radiometric dating is self-checking, because the data (after certain preliminary calculations are made) are fitted to a straight line (an "isochron") by means of standard linear regression methods of statistics.Here is one example of an isochron, based on measurements of basaltic meteorites (in this case the resulting date is 4.4 billion years) [Basaltic1981, pg. Skeptics of old-earth geology make great hay of these examples.For example, creationist writer Henry Morris [Morris2000, pg.Geology is the study of the composition and physical properties of rocks, minerals, gems and other related earth materials, including diamonds and crystals.Scientists gain an understanding of the Earth's history by studying its composition.