Ice now covering Edward VII Peninsula appears to thin out in all directions 

 from the center where it is 2, 100 feet thick and 3,200 feet above sea level (Byrd, 

 1935) . The western shoreline of Sulzberger Bay is characterized by steep slopes 

 where the ice moves down to the bay between the peaks of the Alexandra Mountains. 

 Area tension cracks on these slopes are quite numerous, reflecting, perhaps, a 

 steepening of the slope of the surface of the underlying- bedrock. Large undulations 

 lead out from these disturbed areas, curving north toward the head of the bay Indi- 

 cating direction of differential movement within the floating ice shelf (Wade 1937a, 

 p . 587) . 



The present ice surface south of Sulzberger Bay forms an E-W ridge. Its crest 

 rises toward the Rockefeller Plateau (Behrendt, et al ., 1962) . Since, according 

 to Nye (1959), ice flows over large areas in the direction of the slope of the ice 

 surface, ice north of the crest flows into Sulzberger Bay, ice south of the crest 

 flows south and then west into the Ross embayment to become port of the north- 

 flowing Ross Ice Shelf. 



The present ice sheets affecting the Sulzberger Bay area have their accumu- 

 lations on Edward VII Peninsula (Wade, 1937a), on the Rockefeller Plateau, and 

 perhaps on the interconnecting ice crest. 



D . Prior Glaciation 



Wade (1937) found considerable evidence of a period of glaciation much 

 greater in extent than presently occurs along the crest of the Edsel Ford Range. 

 For example, on the rather flat crest of Mt. Woodward he found chattermarks and 

 crescentic gouge marks 600 feet above the present level of valley glaciers. The 

 Rea-Cooper massif, 2,800 feet above the level of the shelf ice, has a U-shaped 

 valley cutting across one of its higher peaks which implies a former active glacier 

 high enough lo overflow the massif at Isast 2,000 feet higher than the nearest 

 active ice today . 



Wade (personal communication, 1963) thought the former ice over Edsel Ford 

 Mountains was probably no less than 1,000 feet thicker than the present ice sheet. 



The Ross Ice Shelf, which now floats over its basal moraine (Poulter, 1947; 

 Carey and Ahmad, 1961), may at one time have been a grounded ice cap extend- 

 ing past the present ice barrier to the edge of the continental shelf (Hollin, 1962) 

 (Voronov 1960). Roos (1937) and Taylor (1930) have considered Pennel Bank, 

 near the seaward edge of the continental shelf of the Ross Sea, to be a terminal 



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