Dating of rocks fossils and geologic events lab


In these cases, usually the half-life of interest in radiometric dating is the longest one in the chain, which is the rate-limiting factor in the ultimate transformation of the radioactive nuclide into its stable daughter.Isotopic systems that have been exploited for radiometric dating have half-lives ranging from only about 10 years (e.g., tritium) to over 100 billion years (e.g., samarium-147).Among the best-known techniques are radiocarbon dating, potassium–argon dating and uranium–lead dating.By allowing the establishment of geological timescales, it provides a significant source of information about the ages of fossils and the deduced rates of evolutionary change.On the other hand, the concentration of carbon-14 falls off so steeply that the age of relatively young remains can be determined precisely to within a few decades.



It is therefore essential to have as much information as possible about the material being dated and to check for possible signs of alteration.Radiometric dating is also used to date archaeological materials, including ancient artifacts.Different methods of radiometric dating vary in the timescale over which they are accurate and the materials to which they can be applied.For instance, carbon-14 has a half-life of 5,730 years.

After an organism has been dead for 60,000 years, so little carbon-14 is left that accurate dating can not be established.

Precision is enhanced if measurements are taken on multiple samples from different locations of the rock body.