Rb sr dating ppt
Furthermore, magnesium-isotope anomalies within inclusions of the Allende meteorite show a linear relationship between Al is invoked.
It may surprise some readers to learn that there is no clear answer to this question.
It therefore seems worthwhile to point out that isotopic fractionation does occur during the mass spectrometric ratio measurement.
Strontium isotope measurements are therefore routinely corrected by measuring the (fractionated) Sr) using the appropriate mass dependence of fractionation.
Although the unreliability of the Rb-Sr method for dating is readily demonstrated, it is important that alternative models are developed to explain the observed patterns of strontium isotopes. When diffusive isotope fractionation of Sr isotopes is repeated a sufficient number of times by within-mantle processes on isotopically-anomalous mantle xenoliths (each of which originally had low Sr ratios.
When mixed with variable amounts of terrestrial nonradiogenic strontium, these remnants generate mixing lines indistinguishable from age-indicative Rb-Sr isochrons.