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This is the time scale for the deep ice core from Siple Dome (SDM-A) for the time period -45 B.P. to 8,609 B.P.. It was developed in November 2003 and supersedes all previous time scales for this interval.
The most recent 8654 years of the Siple Dome Antarctica ice core was dated by interpreting the electrical, visual, and chemical properties of the core. The data were interpreted manually and with a computer algorithm. The algorithm interpretation was adjusted to be consistent with atmospheric methane stratigraphic ties to the GISP2 ice core, 10Be stratigraphic ties to the dendrochronology 14C record, and volcanic stratigraphic ties.
Time scales file names show the core, the age range, and the date the time scale was released for general use. Time scales are referenced to years before 1950.
* Taylor, K.C., R.B. Alley, D.A. Meese, M.K. Spencer, E.J. Brook, N.W. Dunbar, R.C. Finkel, A.J. Gow, A.V. Kurbatov, G.W. Lamorey, P.A. Mayewski, E.A. Meyerson, K. Nishiizumi, and G.A. Zielinski. 2004. Dating the Siple Dome (Antarctica) ice core by manual and computer interpretation of annual layering. Journal of Glaciology 50(170): 453-461.