dating — I In geology and archaeology, the process of determining an object s or event s place within a chronological scheme. Scientists may use either relative dating, in which items are sequenced on the basis of stratigraphic clues (see stratigraphy) or … Universalium
Isotopic labeling — (or isotopic labelling) is a technique for tracking the passage of a sample of substance through a system. The substance is labeled by including unusual isotopes in its chemical composition. If these unusual isotopes are later detected in a… … Wikipedia
Radiometric dating — (often called radioactive dating) is a technique used to date materials such as rocks, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates.[1]… … Wikipedia
Argon–argon dating — Argon argon (or 40Ar/39Ar) dating is a radiometric dating method invented to supersede potassium argon (K Ar) dating in accuracy. In this technique, the decay of 40K to 40Ar* (* indicates radiogenic) is used to date geological events,… … Wikipedia
Lead-lead dating — is a method for dating geological samples, normally based on whole rock samples of material such as granite. For most dating requirements it has been superseded by uranium lead dating (U Pb dating), but in certain specialized situations (such as… … Wikipedia
Isochron dating — is a common technique of radiometric dating and is applied to date certain events, such as crystallization, metamorphism, shock events, and differentiation of precursor melts, in the history of rocks. Isochron dating can be further separated into … Wikipedia
Samarium-neodymium dating — is useful for determining the age relationships of rocks and meteorites, based on decay of a long lived Sm isotope to a radiogenic Nd isotope. Nd isotope ratios are used to provide information on the source of igneous melts as well as to provide… … Wikipedia
Potassium-argon dating — or K Ar dating is a radiometric dating method used in geochronology and archeology. It is based on measuring the products of the radioactive decay of potassium (K), which is a common element found in materials such as micas, clay minerals, tephra … Wikipedia
helium dating — Method of dating that depends on the production of helium during the decay of radioactive isotopes of uranium and thorium. Because of this decay, the helium content of any mineral or rock capable of retaining helium will increase during the… … Universalium
Incremental dating — techniques allow the construction of year by year annual chronologies, which can be temporally fixed ( i.e., linked to the present day and thus calendar or sidereal time) or floating.Archaeologists use tree ring dating (dendrochronology) to… … Wikipedia
Rhenium-osmium dating — is a form of radiometric dating based on the beta decay of the isotope 187Re which usually has a half life of 4.16×1010 y [ Smoliar, M.I., Walker, R.J. and Morgan, J.W. (1996). Re Os ages of group IIA, IIIA, IVA, and IVB iron meteorites. Science… … Wikipedia