Surficial geology and geomorphology of eastern and central Wright Valley, Antarctica

Surficial deposits in eastern and central Wright Valley, Antarctica, record multiple inland incursions of grounded ice from the Ross Sea Embayment. Glacial geologic mapping, coupled with 42 AMS 14C dates of lacustrine algae and 10 40Ar/39Ar dates of basalt erratics, indicate westward ice expansion at least eight times during the Pliocene and Quaternary. The most extensive westward incursion resulted in an advance of at least 21 km beyond the margin of present-day Wright Lower Glacier, accompanied by ice thickening of ≥500 m at the location of the present-day Wilson Piedmont Glacier in the eastern valley mouth. Large proglacial lakes and glaciolacustrine sedimentation coincide with at least some of these advances.