Radiometric age dating for kids

27-Jan-2019 13:43

Different isotopes have different half-lives and sometimes more than one present isotope can be used to get an even more specific age of a fossil.

by Tas Walker A geologist works out the relative age of a rock by carefully studying where the rock is found in the field.

These were then eroded and Sedimentary Rocks B were deposited.

Geologists often need to know the age of material that they find.

Some critics, particularly religious fundamentalists, argue that neither fossils nor dating can be trusted, and that their interpretations are better.

Other critics, perhaps more familiar with the data, question certain aspects of the quality of the fossil record and of its dating.

The results showed that Ötzi died over 5000 years ago, sometime between 33 BC. Uranium has a very long half-life and so by measuring how much uranium is left in a rock its approximate age can be worked out.

Our understanding of the shape and pattern of the history of life depends on the accuracy of fossils and dating methods.

This is different to relative dating, which only puts geological events in time Most absolute dates for rocks are obtained with radiometric methods.

In the past 150 years they have not found any fossils that Darwin would not have expected.

New discoveries have filled in the gaps, and shown us in unimaginable detail the shape of the great ‘tree of life’.

The field relationships, as they are called, are of primary importance and all radiometric dates are evaluated against them.

For example, a geologist may examine a cutting where the rocks appear as shown in Figure 1.

This is different to relative dating, which only puts geological events in time Most absolute dates for rocks are obtained with radiometric methods.

In the past 150 years they have not found any fossils that Darwin would not have expected.

New discoveries have filled in the gaps, and shown us in unimaginable detail the shape of the great ‘tree of life’.

The field relationships, as they are called, are of primary importance and all radiometric dates are evaluated against them.

For example, a geologist may examine a cutting where the rocks appear as shown in Figure 1.

There's a small amount of radioactive carbon-14 in all living organisms.