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  2. Radiometric dating - Wikipedia

    en.wikipedia.org/wiki/Radiometric_dating

    Luminescence dating methods are not radiometric dating methods in that they do not rely on abundances of isotopes to calculate age. Instead, they are a consequence of background radiation on certain minerals. Over time, ionizing radiation is absorbed by mineral grains in sediments and archaeological materials such as quartz and potassium ...

  3. Hafnium–tungsten dating - Wikipedia

    en.wikipedia.org/wiki/Hafnium–tungsten_dating

    The radioactive system behind hafnium–tungsten dating is a two-stage decay as follows: 182 72 Hf → 182 73 Ta e − ν e 182 73 Ta → 182 74 W e − ν e. The first decay has a half-life of 8.9 million years, while the second has a half-life of only 114 days, [7] such that the intermediate nuclide tantalum-182 (182 Ta) can effectively be ignored.

  4. Lutetium–hafnium dating - Wikipedia

    en.wikipedia.org/wiki/Lutetium–hafnium_dating

    Lutetium–hafnium dating is a geochronological dating method utilizing the radioactive decay system of lutetium–176 to hafnium–176. [1] With a commonly accepted half-life of 37.1 billion years, [ 1 ] [ 2 ] the long-living Lu–Hf decay pair survives through geological time scales, thus is useful in geological studies. [ 1 ]

  5. Monazite geochronology - Wikipedia

    en.wikipedia.org/wiki/Monazite_geochronology

    Monazite geochronology is a dating technique to study geological history using the mineral monazite. It is a powerful tool in studying the complex history of metamorphic rocks particularly, as well as igneous, sedimentary and hydrothermal rocks. [2] [3] The dating uses the radioactive processes in monazite as a clock.

  6. Argon–argon dating - Wikipedia

    en.wikipedia.org/wiki/Argon–argon_dating

    Argon–argon (or 40 Ar/ 39 Ar) dating is a radiometric dating method invented to supersede potassium–argon (K/Ar) dating in accuracy. The older method required splitting samples into two for separate potassium and argon measurements, while the newer method requires only one rock fragment or mineral grain and uses a single measurement of argon isotopes.

  7. Rhenium–osmium dating - Wikipedia

    en.wikipedia.org/wiki/Rhenium–osmium_dating

    Rhenium–osmium dating is a form of radiometric dating based on the beta decay of the isotope 187 Re to 187 Os. This normally occurs with a half-life of 41.6 × 10 9 y, [ 1 ] but studies using fully ionised 187 Re atoms have found that this can decrease to only 33 y. [ 2 ]

  8. Radioanalytical chemistry - Wikipedia

    en.wikipedia.org/wiki/Radioanalytical_chemistry

    Applications include: forming and characterizing new elements, determining the age of materials, and creating radioactive reagents for specific tracer use in tissues and organs. The ongoing goal of radioanalytical researchers is to develop more radionuclides and lower concentrations in people and the environment.

  9. Samarium-147 - Wikipedia

    en.wikipedia.org/wiki/Samarium-147

    Samarium-147 is used in samarium–neodymium dating.The method of isochron dating is used to find the date at which a rock (or group of rocks) are formed. [5] The Sm-Nd isochron plots the ratio of radiogenic 143 Nd to non-radiogenic 144 Nd against the ratio of the parent isotope 147 Sm to the non-radiogenic isotope 144 Nd.