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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. Radiocarbon dating considerations - Wikipedia

    en.wikipedia.org/wiki/Radiocarbon_dating...

    Since that time the tree-ring data series has been extended to 13,900 years.) [3] Carbon-dating the wood from the tree rings themselves provided the check needed on the atmospheric 14 C / 12 C ratio: with a sample of known date, and a measurement of the value of N (the number of atoms of 14

  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. Geochronometry - Wikipedia

    en.wikipedia.org/wiki/Geochronometry

    The radiometric methods under this category are: U/Pb; U/Th; K-Ar (and Ar-Ar) Rb/Sr; Sm/Nd; Re/Os; Lu/Hf; Each of these methods perform better in different time ranges and has different limitations. However, uranium–lead dating on zircon [4] and Argon-argon dating on sanidine and hornblende are the two single methods that achieve today the ...

  6. Fission track dating - Wikipedia

    en.wikipedia.org/wiki/Fission_track_dating

    Unlike other isotopic dating methods, the "daughter" in fission track dating is an effect in the crystal rather than a daughter isotope.Uranium-238 undergoes spontaneous fission decay at a known rate, and it is the only isotope with a decay rate that is relevant to the significant production of natural fission tracks; other isotopes have fission decay rates too slow to be of consequence.

  7. Calibration (statistics) - Wikipedia

    en.wikipedia.org/wiki/Calibration_(statistics)

    One example is that of dating objects, using observable evidence such as tree rings for dendrochronology or carbon-14 for radiometric dating. The observation is caused by the age of the object being dated, rather than the reverse, and the aim is to use the method for estimating dates based on new observations.

  8. 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 ...

  9. Uranium–uranium dating - Wikipedia

    en.wikipedia.org/wiki/Uranium–uranium_dating

    Uranium–uranium dating is a radiometric dating technique which compares two isotopes of uranium (U) in a sample: uranium-234 (234 U) and uranium-238 (238 U). It is one of several radiometric dating techniques exploiting the uranium radioactive decay series, in which 238 U undergoes 14 alpha and beta decay events on the way to the stable isotope 206 Pb.