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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. 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 ...

  4. Uranium–lead dating - Wikipedia

    en.wikipedia.org/wiki/Uranium–lead_dating

    Uranium–lead dating, abbreviated U–Pb dating, is one of the oldest [1] and most refined of the radiometric dating schemes. It can be used to date rocks that formed and crystallised from about 1 million years to over 4.5 billion years ago with routine precisions in the 0.1–1 percent range. [2] [3] The method is usually applied to zircon.

  5. 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 ...

  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. 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 ]

  8. Uranium-238 - Wikipedia

    en.wikipedia.org/wiki/Uranium-238

    The most common dating method is uranium-lead dating, which is used to date rocks older than 1 million years old and has provided ages for the oldest rocks on Earth at 4.4 billion years old. [14] The relation between 238 U and 234 U gives an indication of the age of sediments and seawater that are between 100,000 years and 1,200,000 years in ...

  9. 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 ...