- rubidium-strontium dating
/rooh bid"ee euhm stron"shee euhm, -sheuhm, -tee euhm/, Geol.a radiometric dating method whereby the ratio of rubidium isotope to strontium in a mineral is used to calculate the age of the mineral, based on the rate of radioactive decay of rubidium to strontium.[1965-70]
* * *Method of estimating the age of rocks, minerals, and meteorites from measurements of the amount of the stable isotope strontium-87 formed by the decay of the unstable isotope rubidium-87 that was present in the rock at the time of its formation.The method is applicable to very old rocks because the transformation is extremely slow: the half-life, or time required for half the initial quantity of rubidium-87 to disappear, is approximately 48.8 billion years. See also dating.
* * *method of estimating the age of rocks, minerals, and meteorites from measurements of the amount of the stable isotope strontium-87 formed by the decay of the unstable isotope rubidium-87 (rubidium) that was present in the rock at the time of its formation. Rubidium-87 comprises 27.85 percent of the total atomic abundance of rubidium, and of the four isotopes of strontium, only strontium-87 is formed by its decay. The method is applicable to very old rocks because the transformation is extremely slow: the half-life, or time required for half the initial quantity of rubidium-87 to disappear, is approximately 50 billion years.Most minerals that contain rubidium also have some strontium incorporated when the mineral was formed, so a correction must be made for this initial amount of strontium to obtain the radiogenic increment (i.e., the increase due to decay of rubidium-87).
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Rubidium-strontium dating — The rubidium strontium dating method is a radiometric dating technique that geologists use to determine the age of rocks.Development of this process was aided by Fritz Strassmann, who later moved onto discovering nuclear fission with Otto Hahn… … Wikipedia
rubidium-strontium dating — noun geological dating based on the proportions of radioactive rubidium into its decay product strontium; radioactive rubidium has a half life of 47,000,000,000 years • Hypernyms: ↑dating, ↑geological dating * * * /rooh bid ee euhm stron shee… … Useful english dictionary
rubidium - strontium dating — … Useful english dictionary
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
Rubidium — krypton ← rubidium → strontium K ↑ Rb ↓ … Wikipedia
dating — noun use of chemical analysis to estimate the age of geological specimens • Syn: ↑geological dating • Derivationally related forms: ↑date • Hypernyms: ↑chemical analysis, ↑qualitative analysis • … Useful english dictionary
Isotopes of rubidium — Rubidium (Rb) has 24 isotopes, with naturally occurring rubidium being composed of just two isotopes; Rb 85 (72.2%) and the radioactive Rb 87 (27.8%). Normal mixes of rubidium are radioactive enough to fog photographic film in approximately 30 to … 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.… … Wikipedia
geological dating — noun use of chemical analysis to estimate the age of geological specimens • Syn: ↑dating • Derivationally related forms: ↑date (for: ↑dating) • Hypernyms: ↑chemical analysis, ↑ … Useful english dictionary
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