On Black Island and Brown Peninsula a sequence of moraine deposits and topographic benches is interpreted as reflecting four cycles of alternating climate. The previously described glacio-marine Scallop Hill Formation is related to the second of the climatic cycles, the Taylor Formation to the fourth. Erratic boulders of marine Tertiary sediments previously reported from McMurdo Sound are confined to the moraine of the third cycle. Benches may have been formed by earlier ice shelves like the present Ross Ice Shelf, and have been raised by progressive differential uplift.