A first chronology for the East GReenland Ice core Project (EGRIP) over the Holocene and last glacial termination has been derived by transferring the annual layer counted Greenland Ice Core Chronology 2005 (GICC05) from the NGRIP core to the EGRIP core using 381 matchpoints of mainly on volcanic events and common patterns (peaks and dips) recorded by electrical conductivity measurement (ECM) and dielectrical profiling (DEP) records.

EGRIP bag depths have been transferred to NGRIP by linear interpolation between match points, and from these, GICC05 ages were obtained using the NGRIP (depth, age) relationship.All ages are given in whole years b2k (kyears before A.D. 2000) and are transfered to ka b2k.The match points are based on ECM and DEP data (patterns, peaks and dips).The NGRIP1 core reaches down to a depth of 1372 m. The NGRIP2 core (drilled 20 meters away from the NGRIP1 core) reaches from surface to bedrock, but high-resolution measurements apart from DEP have only been carried out downwards from 1346 m. In the 26 m overlap zone, the cores are offset by 0.43 m on average, probably due to uncertainties in the logging procedure (see Schøtt Hvidberg et al., Ann. Glac. 35, 2002). Thus, the same features appear at larger depths in the NGRIP1 than in the NGRIP2 core. Here, we derive the EGRIP time scale from the match points between EGRIP and NGRIP1 until 9813 a b2k and the match points between EGRIP and NGRIP2 below this.The GICC05 chronology extends to 60.2 ka b2k, and has been published in several stages. The relevant references here are:- Main Holocene part: Vinther et al., Journ. Geophys. Res. 111, D13102, 2006.- Late glacial / Early Holocene part: Rasmussen et al., Journ. Geophys. Res. 111, D06102, 2006.The value "MCE" is the Maximum Counting Error of the GICC05 time scale. See Rasmussen et al. (Journ. Geophys. Res. 111, D06102, 2006) for a full description. In a standard deviation context, the maximum counting error should be regarded as 2 sigma as discussed in Andersen et al., Quat. Sci. Rev. 25, p. 3246-3257, 2006.The counting error does not include uncertainty contributions from the time scale transfer. Most match points are accurate to 10 cm or better (i.e. a few years), but in some sections the synchronization is less robust. The time scale transfer involves interpolation over relatively long sections resulting in significant relative uncertainty.Synchronization carried out by S. Mojtabavi, G. Sinnl, M.S. Jensen and S.O. Rasmussen Inquiries regarding this data file: EGRIP dating consortium chairman Sune Olander Rasmussen, olander@nbi.ku.dk.