The origin of geomorphology of the submarine topography features shown on 

 Figure 5 con best be discussed after reviewing the areal geology, present sedi- 

 mentation, and present and prior glaciation of the area under consideration. 



A . Areal Geology and Glaciology 



The geology, geomorphology, and glaciology of the land masses bordering 

 the eastern Ross Sea and Sulzberger Bay have a direct bearing on the Pleistocene 

 history of the adjacent continental shelf. 



Figure 5 shows the outline and the surface topography of the Ice cap and its 

 outlet glaciers, the trends and elevations of the protruding rock outcrops, and 

 the names and elevations of the mouhtains . Figure 2 shows the approximate posi- 

 tion of the rapidly changing front of the present floating Ice shelves. 



According to Wade (1937), the Edsel Ford Mountains are folded, partly meta- 

 morphosed sediments with concordant granite intrusions that probably preceded 

 complete folding. The beds are mostly vertical and strike NW-SE in the south 

 end of the range, but their strike swings through N-S to NNE in the northern part. 

 Folding and faulting are closely related. The sediments are folded into broad 

 anticlines and syncllnes; the axes trend NW and plunge 30" to 40° In the same 

 direction (Warner, 1945). Passel (1945) noted some sediments exceeded 15,000 

 feet, and he also found basic lavas and ash along the axis of Fosdick Range that 

 he considered as evidence of fairly recent volcanic activity because the volcanic 

 cones apparently had not been overridden by the Pleistocene ice advances as were 

 the rocks upon which the cones are situated. 



The Rockefeller Mountains according to Wade (1945) appear to be metamor- 

 phosed sediments that have been intruded by a granitic botholith that structurally 

 and petrographicallyresembles the Edsel Ford Range. The fold axes trend NW-SE. 



Fairbridge (1952) contends that Edward VII Peninsula appears to be separated 

 from the Edsel Ford Mountains by block faulting. A seismic profile across Marie 

 Byrd Land by Thiel and Ostenso (1961) indicates the presence of a large depres- 

 sion in the sub-ice bedrock. This depression is aligned southeast of the bight of 

 Sulzberger Bay. A deep glacial trough is incised into the floor of Sulzberger Bay 

 in a SW direction along this same line. The rock outcrops near the SW edge of 

 the bay diso trend SE. 



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