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  2. Radiometric dating - Wikipedia

    en.wikipedia.org/wiki/Radiometric_dating

    The basic equation of radiometric dating requires that neither the parent nuclide nor the daughter product can enter or leave the material after its formation. The possible confounding effects of contamination of parent and daughter isotopes have to be considered, as do the effects of any loss or gain of such isotopes since the sample was created.

  3. Isochron dating - Wikipedia

    en.wikipedia.org/wiki/Isochron_dating

    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 mineral isochron dating and whole rock isochron dating; both techniques are applied ...

  4. 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 ...

  5. Thermochronology - Wikipedia

    en.wikipedia.org/wiki/Thermochronology

    Radiometric dating is how geologist determine the age of a rock. In a closed system , the amount of radiogenic isotopes present in a sample is a direct function of time and the decay rate of the mineral. [ 2 ]

  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. Geochronology - Wikipedia

    en.wikipedia.org/wiki/Geochronology

    [2] [3] [4] Two or more radiometric methods can be used in concert to achieve more robust results. [5] Most radiometric methods are suitable for geological time only, but some such as the radiocarbon method and the 40 Ar/ 39 Ar dating method can be extended into the time of early human life [6] and into recorded history. [7]

  8. Monazite geochronology - Wikipedia

    en.wikipedia.org/wiki/Monazite_geochronology

    Monazite is a rare-earth-element phosphate mineral, with the chemical formula e.g. (Ce, La, Nd, Th, Y)PO 4. It appears in a small amount as an accessory mineral in many igneous, metamorphic and sedimentary rocks. [2] Monazite minerals contain significant amounts of radioactive elements Th and U, which trigger radioactive processes.

  9. Surface exposure dating - Wikipedia

    en.wikipedia.org/wiki/Surface_exposure_dating

    Surface exposure dating is a collection of geochronological techniques for estimating the length of time that a rock has been exposed at or near Earth's surface. Surface exposure dating is used to date glacial advances and retreats, erosion history, lava flows, meteorite impacts, rock slides, fault scarps, cave development, and other geological events.