Summary: JOURNAL OF GEOPHYSICAL RESEARCH, VOL. ???, XXXX, DOI:10.1029/2005JD006921, 2006
A synchronized dating of three Greenland ice cores throughout
B. M. Vinther, H. B. Clausen, S. J. Johnsen, S. O. Rasmussen, K. K. Andersen, S.
L. Buchardt, D. Dahl-Jensen, I. K. Seierstad, M-L. Siggaard-Andersen, J. P.
Steffensen and A. Svensson
Ice and Climate, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
J. Olsen and J. Heinemeier
AMS 14C Dating Centre, Department of Physics and Astronomy, University of Aarhus, Aarhus, Denmark.
Abstract. As part of the effort to create the new Greenland Ice Core Chronology 2005
(GICC05) a synchronized stratigraphical timescale for the Holocene parts of the DYE-
3, GRIP and NGRIP ice cores is made by using volcanic reference horizons in electri-
cal conductivity measurements to match the cores.
The main annual layer counting is carried out on the most suited records only, exploit-
ing that the three ice cores have been drilled at locations with different climatic con-
ditions and differences in ice flow. However, supplemental counting on data from all cores
has been performed between each set of reference horizons in order to verify the valid-
ity of the match. After the verification, the main dating is transferred to all records us-
ing the volcanic reference horizons as tie points. An assessment of the mean annual layer
thickness in each core section confirms that the new synchronized dating is consistent