Hornblende 40Ar-39Ar data from debris from the basal ice of the Byrd ice core, central West Antarctica

<p>This dataset comprises of hornblende 40Ar/39Ar ages. Hornblende grains were picked from debris melted from three intervals of basal ice from the Byrd ice core. We include data for all 129 40Ar/39Ar dated hornblende grains, but note that only ages when an 5.0E-18 Mol 39Ar threshold was exceeded are considered reliable (n = 33) and that data from grains with less than 1.5E-17 Mol 39Ar should be interpreted with caution.&nbsp;The ice core the debris was extracted from was drilled at 80<i><strong>°</strong></i>&nbsp;0.1'S, 119<i><strong>°</strong></i> 31.0'W at Byrd Station, West Antarctica, in January 1968.</p>