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  2. Isotope analysis - Wikipedia

    en.wikipedia.org/wiki/Isotope_analysis

    Archaeological materials, such as bone, organic residues, hair, or sea shells, can serve as substrates for isotopic analysis. Carbon, nitrogen and zinc isotope ratios are used to investigate the diets of past people; these isotopic systems can be used with others, such as strontium or oxygen, to answer questions about population movements and cultural interactions, such as trade.

  3. Isotope dilution - Wikipedia

    en.wikipedia.org/wiki/Isotope_dilution

    Isotope dilution is analogous to the mark and recapture method, commonly used in ecology to estimate population size. For instance, consider the determination of the number of fish (n A) in a lake. For the purpose of this example, assume all fish native to the lake are blue. On their first visit to the lake, an ecologist adds five yellow fish ...

  4. List of radioactive nuclides by half-life - Wikipedia

    en.wikipedia.org/wiki/List_of_radioactive...

    This is a list of radioactive nuclides (sometimes also called isotopes), ordered by half-life from shortest to longest, in seconds, minutes, hours, days and years. Current methods make it difficult to measure half-lives between approximately 10 −19 and 10 −10 seconds.

  5. Bateman equation - Wikipedia

    en.wikipedia.org/wiki/Bateman_equation

    Quantity calculation with the Bateman-Function for plutonium-241 While the Bateman formula can be implemented in a computer code, if λ j ≈ λ i {\displaystyle \lambda _{j}\approx \lambda _{i}} for some isotope pair, catastrophic cancellation can lead to computational errors.

  6. Hydrogen isotope biogeochemistry - Wikipedia

    en.wikipedia.org/wiki/Hydrogen_isotope...

    The amount of liquid-vapor equilibrium fractionation for hydrogen isotopes is about 8x that of oxygen isotopes at Earth surface temperatures, which reflects the relative mass differences of the two isotope systems: 2 H is 100% heavier than 1 H, 18 O is 12.5% heavier than 16 O. Above the boundary layer, there is a transition zone with relative ...

  7. Isotope geochemistry - Wikipedia

    en.wikipedia.org/wiki/Isotope_geochemistry

    Isotope geochemistry is an aspect of geology based upon the study of natural variations in the relative abundances of isotopes of various elements.Variations in isotopic abundance are measured by isotope-ratio mass spectrometry, and can reveal information about the ages and origins of rock, air or water bodies, or processes of mixing between them.

  8. Reference materials for stable isotope analysis - Wikipedia

    en.wikipedia.org/wiki/Reference_materials_for...

    The δ values and absolute isotope ratios of common reference materials are summarized in Table 1 and described in more detail below. Alternative values for the absolute isotopic ratios of reference materials, differing only modestly from those in Table 1, are presented in Table 2.5 of Sharp (2007) [1] (a text freely available online), as well as Table 1 of the 1993 IAEA report on isotopic ...

  9. Isoscape - Wikipedia

    en.wikipedia.org/wiki/Isoscape

    The word isoscape is derived from isotope landscape and was first coined by Jason B. West. [1] [2] Isoscapes of hydrogen , carbon , oxygen , nitrogen , strontium and sulfur [ 3 ] have been used to answer scientific or forensic questions regarding the sources, partitioning, or provenance of natural and synthetic materials or organisms via their ...