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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. Absolute dating - Wikipedia

    en.wikipedia.org/wiki/Absolute_dating

    Other radiometric dating techniques are available for earlier periods. One of the most widely used is potassium–argon dating (K–Ar dating). Potassium-40 is a radioactive isotope of potassium that decays into argon-40. The half-life of potassium-40 is 1.3 billion years, far longer than that of carbon-14, allowing much older samples to be dated.

  5. Rubidium–strontium dating - Wikipedia

    en.wikipedia.org/wiki/Rubidium–strontium_dating

    The rubidium–strontium dating method (Rb–Sr) is a radiometric dating technique, used by scientists to determine the age of rocks and minerals from their content of specific isotopes of rubidium (87 Rb) and strontium (87 Sr, 86 Sr). One of the two naturally occurring isotopes of rubidium, 87 Rb, decays to 87 Sr with a half-life of 49.23 ...

  6. K–Ar dating - Wikipedia

    en.wikipedia.org/wiki/K–Ar_dating

    Potassium–argon dating, abbreviated K–Ar dating, is a radiometric dating method used in geochronology and archaeology. It is based on measurement of the product of the radioactive decay of an isotope of potassium (K) into argon (Ar).

  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. Category:Radiometric dating - Wikipedia

    en.wikipedia.org/wiki/Category:Radiometric_dating

    Radionuclides used in radiometric dating (16 P) Pages in category "Radiometric dating" The following 30 pages are in this category, out of 30 total.

  9. Isochron dating - Wikipedia

    en.wikipedia.org/wiki/Isochron_dating

    One of the best known isotopic systems for isochron dating is the rubidium–strontium system. Other systems that are used for isochron dating include samarium–neodymium , and uranium–lead . Some isotopic systems based on short-living extinct radionuclides such as 53 Mn , 26 Al , 129 I , 60 Fe and others are used for isochron dating of ...