The first two core samples (NEL 394 and NEL 395), 

 obtained from the top of deep oceanic ridges, are similar in 

 that they both consist of diatomaceous globigerina ooze. 

 Also a flood of G. pachyderma , a pelagic polar species, is 

 present in both of the samples. A fresh granite chip found in 

 NEL 395 from Kerguelen-Gaussberg Ridge suggests that this 

 structure may be, in part, granitic; however, this cannot be 

 definitely established because such chips might reach their 

 present location by ice rafting in this part of the world. 

 The finding of globigerina ooze in a zone previously considered 

 to be covered by diatomaceous ooze may be due to the topo- 

 graphically high position at which the samples were taken. 

 In this case, the light diatomaceous material would have been 

 largely winnowed out by current action and then transported 

 into the surrounding basins. This is in line with recent 

 observations elsewhere which have shown that topographic 

 highs on the sea floor, regardless of depth, are covered with 

 coarse sediment. Bottom currents at great depths are 

 generally considered to be weak but currents associated 

 with eddies with vertical axes or with internal waves are 

 probably strong enough to stir up the finer bottom material. 

 Thus a mechanism probably exists that sweeps the finest 

 sediment from topographic highs. 



Core sample NEL 396 was obtained from a depth of 2000 

 fathoms at the base of the continental slope of Antarctica in 

 the vicinity of the Shackleton Ice Shelf. It consists of green 

 mud and sand, and the poor sorting suggests that here the 

 deposition of material rafted by ice was important. The 

 presence of two cleanly washed sand layers is noteworthy 

 in that it shows that effective currents must have existed even 

 at this great depth. 



The four bottom samples, NEL 397, 398, 399, 400, (see 

 table 11) were obtained with an underway sampler, the "scoop- 

 fish," in the shallow waters of Bass Strait, Australia. All of 

 the samples are similar in that they consist of a coarse shell 

 sand. The performance of this new device which permits 

 underway sampling was entirely satisfactory. It was used 

 on the bathythermograph winch at speeds up to approximately 

 8 knots. 



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