Radiocarbon dating bone collagen
For samples with sufficient sample material remaining after AMS analysis, stable isotopes (N) and C to N ratios will be measured on our EA-IRMS as a further test of collagen quality. Wood & Charcoal: As trees can be long-lived, wood and charcoal may have an in-built age associated with them If possible, either small twigs or outer rings of the tree should be selected for dating.If these are not available then short-lived species should be selected if possible; identifications must be done before samples are sent for radiocarbon dating.1988 and using the ultrafilter cleaning method of Bronk Ramsey et al. A collagen yield of less than ~1% means that the sample was not well preserved and is unacceptable for dating purposes.These samples will not proceed to the final AMS stages.Identifiable terrestrial plant remains (macrofossils) are therefore usually the preferred samples for radiocarbon dating lake sediments.There is the possibility of re-worked macrofossils being deposited in the lake.
Please remove any roots from bulk samples before sending them.
The FRE may be estimated by radiocarbon dating the surface sediment, aquatic plants or mollusks but it may also have varied over time.
This is less of a problem in 'softwater' regions, but glacial meltwater may have added old carbon to some lakes.
Generally monospecific planktonic samples are selected for this purpose.
Contaminants: Please indicate on the submission form if there are any known contaminants which could effect the radiocarbon age.