Measuring stable isotopes of hydrogen and oxygen in ice by means of laser spectrometry: the Bølling transition in the Dye-3 (south Greenland) ice core 

Annals of Glaciology, 35, p. 125-130, 2002 

R. van Trigt, H.A.J. Meijer and E.R. Th. Kerstel
Centre for Isotope Research (CIO), Nijenborgh 4, 9747 AG Groningen, The Netherlands.
A.E. Sveinbjörnsdottir
Science Institute, University of Iceland, Dunhaga 3, IS-107 Reykjavik, Iceland.
S.J. Johnsen
Geofysisk Afdeling, Niels Bohr Instituttet for Astronomi, Fysik og Geofysik, Københavns Universitet

ABSTRACT.
We report on the first application of a new technique in ice-core research, based on direct absorption infrared laser spectrometry (LS), for measuring ²H, ¹⁷O and ¹⁸O isotope ratios. The data are used to calculate the deuterium excess d (defined as δ²H - 8δ¹⁸O) for a section of the Dye-3 (south Greenland) deep ice core around the Bølling transition (14 500 BP). The precision of LS is slightly better than that of most traditional methods for deuterium, but not for the oxygen isotopes. The ability to measure δ¹⁷O is new and is used here to improve the precision of the δ¹⁸O determination. Still, the final precision for δ¹⁸O remains inferior to traditional isotope ratio mass spectrometry (IRMS). Therefore, deuterium excess was calculated from a combination of the LS and IRMS isotope determinations.