Norwegian corals: radiocarbon and stable isotopes in Lophelia pertusa

• Published in: Boreas
• Main Authors: MIKKELSEN, NAJA, ERLENKEUSER, HELMUT, KILLINGLEY, JOHN S., BERGER, WOLFGANG H.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1982
• Subjects: Lophelia pertusa
• Online Access: http://dx.doi.org/10.1111/j.1502-3885.1982.tb00534.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1502-3885.1982.tb00534.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1502-3885.1982.tb00534.x

The ahermatypic coral Lophelia pertusa which produces aragonitic skeletons is widely distributed along the Norwegian coast. Specimens from a number of localities have been analyzed for oxygen and stable carbon isotope composition and 14 C age. Stable isotope ratios of recent corals provide information on growth rate and seasonality of oceanographic conditions. Lophelia can be useful in paleoenvironmental reconstructions. 14 C dates of fossil Lophelia from Drøak in the Oslofjord, collected from 20 m ahove and 40 m below present day sea‐level, indicate regional extinction between 8700 and 7800 years ago. We suggest that the extinction resulted from the cut‐off of deep waters by a rising sill in connection with the postglacial shoreline displacement. Radiocarbon dating of coral bushes suggests a fairly rapid growth rate as older and younger parts of recent corals do not reveal any difference in activity despite the short time scale of the history of bomb‐produced 14 C in the oceans.