samarium-neodymium dating

geology

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July 13, 2026

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Samarium-neodymium dating is a geochronological method used to determine the age of rocks and minerals. It relies on the radioactive decay of samarium-147 (¹⁴⁷Sm) into neodymium-143 (¹⁴³Nd). This method is particularly useful for dating certain geological materials, including mafic igneous rocks and meteorites.12

The samarium-neodymium (Sm-Nd) system is valuable because both parent and daughter isotopes have similar chemical properties, which can minimize errors caused by diffusion or alteration. The method uses the isochron technique, where data from multiple samples are plotted to determine a precise age. While other dating methods may be more precise, the Sm-Nd method is effective when other systems, like rubidium-strontium, have been disturbed. It has been successfully applied to lunar rocks and minerals like garnet.13

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Samarium–neodymium method
The radioactive decay of samarium of mass 147 (¹⁴⁷Sm) to neodymium of mass 143 (¹⁴³Nd) has been shown to be capable of providing useful isochron ages for certain geologic materials. Both parent and daughter belong to the rare-earth element group, which is itself…
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The radioactive decay of samarium of mass 147 (¹⁴⁷Sm) to neodymium of mass 143 (¹⁴³Nd) has been shown to be capable of providing useful isochron ages for certain geologic materials. Both parent and daughter belong to the rare-earth element group, which is itself…
Read More