Discover the new method

to study the past

Oak leaf

X 10

X 20

Overview of isotopes

Our research team specialises in using tree-rings not just for dating, but also to reconstruct the climate of the past. We do not only use ring widths, but also study the chemistry of the wood, specifically the stable (non-radioactive) isotopes of carbon and oxygen. The carbon isotopes vary mainly in response to the amount of summer sunshine and the oxygen isotopes to summer rainfall.


The isotopic match between trees is much stronger than for ring widths. This means that it is possible to use the annual pattern of isotopic variability to date wooden artefacts with far fewer rings than are currently required. Also, because ring widths and the two isotopes are only weakly related to each other, where all three indicators identify the same date then confidence in the match is significantly enhanced.


At the moment this dating method is not widely available because there are no master chronologies for isotopes in the UK against which to match undated samples. This is what we will provide to the community through this project.

Using special corers we remove samples from living trees and old buildings. Sampling does not cause untoward harm to the trees or damage the buildings. Often, we collect samples from structures under archaeological investigation to establish their age and construction history. For very old timbers, many hundreds or thousands of years old, we can sample logs preserved in peat bogs and sediments.


Living trees


Stage 5

The primary building block of a tree ring is cellulose.