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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. 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 ]

  4. Luminescence dating - Wikipedia

    en.wikipedia.org/wiki/Luminescence_dating

    Luminescence dating refers to a group of chronological dating methods of determining how long ago mineral grains were last exposed to sunlight or sufficient heating. It is useful to geologists and archaeologists who want to know when such an event occurred.

  5. Isochron dating - Wikipedia

    en.wikipedia.org/wiki/Isochron_dating

    An isochron diagram will only give a valid age if all samples are cogenetic, which means they have the same initial isotopic composition (that is, the rocks are from the same unit, the minerals are from the same rock, etc.), all samples have the same initial isotopic composition (at t 0), and the system has remained closed.

  6. Closure temperature - Wikipedia

    en.wikipedia.org/wiki/Closure_temperature

    In radiometric dating, closure temperature or blocking temperature refers to the temperature of a system, such as a mineral, at the time given by its radiometric date.In physical terms, the closure temperature is the temperature at which a system has cooled so that there is no longer any significant diffusion of the parent or daughter isotopes out of the system and into the external ...

  7. 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 ...

  8. 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.

  9. Uranium–thorium dating - Wikipedia

    en.wikipedia.org/wiki/Uranium–thorium_dating

    Uranium–thorium dating, also called thorium-230 dating, uranium-series disequilibrium dating or uranium-series dating, is a radiometric dating technique established in the 1960s which has been used since the 1970s to determine the age of calcium carbonate materials such as speleothem or coral.