isochron method
Quick Summary
The isochron method is a technique used in geology for absolute dating, determining the age of rocks and minerals. It relies on measuring the amounts of radioactive isotopes and their "daughter" products within a sample. Radioactive isotopes decay at a constant rate, characterized by their half-life, which is the time it takes for half of the parent atoms to transform into daughter atoms.1
The isochron method presents data in a way that accounts for both parent and daughter isotopes relative to an initial background amount of the daughter isotope. This allows for the calculation of the time elapsed since the mineral or rock formed. The rubidium-strontium (Rb-Sr) dating system was one of the first to extensively use the isochron method. This technique is particularly useful for dating igneous rocks and can provide precise ages, even if some daughter isotopes have escaped the host minerals, as long as they remain within the rock.23
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datingPrinciples of isotopic datingIn whole-rock isochron methods that make use of the rubidium-strontium or samarium-neodymium decay schemes, a series of rocks or minerals are chosen that can be assumed to have the same age and identical abundances of their initial isotopic ratios. The results are then tested for the internal…
Read MoreIn whole-rock isochron methods that make use of the rubidium-strontium or samarium-neodymium decay schemes, a series of rocks or minerals are chosen that can be assumed to have the same age and identical abundances of their initial isotopic ratios. The results are then tested for the internal…
Read More- datingThe isochron method
Many radioactive dating methods are based on minute additions of daughter products to a rock or mineral in which a considerable amount of daughter-type isotopes already exists. These isotopes did not come from radioactive decay in the system but rather formed during the…
Read MoreMany radioactive dating methods are based on minute additions of daughter products to a rock or mineral in which a considerable amount of daughter-type isotopes already exists. These isotopes did not come from radioactive decay in the system but rather formed during the…
Read More