obtained (Sample GLP-4, Fig . 2) . This sample contained angular to subangular 

 metamorphlc, granitic, and volcanic rock fragments, many of them pebble-size 

 and larger. The northeastward extension of this ridge was deduced from the chronic 

 presence of grounded icebergs over the area . It seems probable that grounded Ice- 

 bergs may have scraped away the veneer of marine sediment, exposing morainal 

 material of longitudinal ridges. 



On the basis of the following observations, the longitudinal ridges of the 

 Sulzberger Bay area are interpreted by the writer as end moraines formed by the 

 continental ice sheet during a pause in its retreat during the Holocene transgression: 



] . Glaciological and eustatic considerations point to the probability that 

 ice sheets of glacial maxima advanced to the continental shelf edge, beyond 

 the line of the existing longitudinal ridges. 



2 . The similarity of these ridges to those of other areas which have been 

 more thoroughly surveyed and found to be morainal (e.g., Georges Bank - 

 Shepqrd, et al ., 1934) indicates that they may be analogous features. 



3. The occurrence of the longitudinal ridges at the seaward rims of apparently 

 glacially-carved depressions suggests that the ridges may be the resting place 

 of some of the material scooped out of the depressions . 



4. The relief of the longitudinal ridges above the outer shelf surface and 

 their mound-like shape suggests that they have been dumped or pushed onto 

 the outer shelf. 



D . Transverse Ridges 



A sand-covered, current-swept, transverse ridge extends north and northeast 

 from Cape Col beck. At Its narrow shoreward end. It Is bordered on the west by 

 the tongue-shaped depression and on the east It is abutted by the longitudinal 

 depression . At its broader seaward end It merges with the outer shelf. Two as- 

 pects of the morphology of this ridge are worth emphasizing: (1) It is tangent to 

 the western shore of Edward VII Peninsula, and (2) It appears to be superimposed 

 upon the Inner shelf, the longitudinal depression, and the outer shelf. 



Another transverse ridge, also sand-covered and corrent-swept, extends west 

 from the western shore of Edward VII Peninsula . This ridge, like the previous one, 

 is narrow and relatively shallow at Its shoreward end . The ridge fans out onto 

 the deeper shelf of the Ross Sea where it appears to end within a few tens of miles. 

 This ridge Is abutted on either side by north-^outh-trendtng depressjons . This 

 second transverse ridge also appears to be superimposed over the Inner shelf, a 

 depression, and the deeper shelf. The fact that this ridge Is roughfy parallel to 

 the front of the Ross Ice Shelf (compare Figt. 2 and 5) may be significant. 



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