Isotopic systems that have been exploited for radiometric dating have half-lives ranging from only about 10 years (e.g., , whose decay rate may be affected by local electron density.
For all other nuclides, the proportion of the original nuclide to its decay products changes in a predictable way as the original nuclide decays over time.
Both the physical geologists and paleontologists could point to evidence that much more time was needed to produce what they saw in the stratigraphic and fossil records.
As one answer to his critics, Kelvin produced a completely independent estimate -- this time for the age of the Sun.
was published, the earth was "scientifically" determined to be 100 million years old. In 1947, science firmly established that the earth was 3.4 billion years old.
Finally in 1976, it was discovered that the earth is "really" 4.6 billion years old… The answer of 25 million years deduced by Kelvin was not received favorably by geologists.
All ordinary matter is made up of combinations of chemical elements, each with its own atomic number, indicating the number of protons in the atomic nucleus.
Scientists use a spectrometer to determine the amount of each parent and daughter isotope in the material.
It is therefore essential to have as much information as possible about the material being dated and to check for possible signs of Precision is enhanced if measurements are taken on multiple samples from different locations of the rock body.
Alternatively, if several different minerals can be dated from the same sample and are assumed to be formed by the same event and were in equilibrium with the reservoir when they formed, they should form an is used which also decreases the problem of nuclide loss.
By finding these values they work out how old the rock or object is.
Radiometric dating is a very accurate way to date the age of an object if the object was in a closed system.