The Edsel Ford Range is located in northwest Marie Byrd Land. It extends for approximately 150 miles along the eastern boundary of Sulz‐berger Bay and acts as a retaining wall to check the advance of ice from the Rockefeller Plateau. The geographic setting is shown in Figure 1. This section of the Antarctic was discovered in 1929 by Admiral Byrd during an exploratory flight that carried his plane to within about 100 miles of the range. A reconnaissance map of the area was constructed from the photographs taken during the flight.1 A four-man sledge party led by Paul Siple, which included in its personnel Stephenson Corey, Olin Stancliff, and the writer, spent 39 days of the short field season in these mountains. From the observations made and from the results of the petrographic analyses of the rocks collected, comparisons have been made and relationships of the Edsel Ford Range . . .