284 



[CHAP. 13 



54°N 



Fig. 2. Outer Silver Pit and Markhams Hole, North Sea. Contours in metres. (After 

 Berthois and Brenot, 1957.) 







000 



1000 



u. 1500 



■£ 2000 



2500 



3000 



South 



North 



Cleft 



Smooth shelf 

 Longitudinal 

 depression 



Continental 

 slope 



Deep-sea 

 floor 



10 



20 



A- 



30 40 50 

 Nauticol miles 



60 



70 



80 



Fig. 3. Transverse profile across the shelf and slope of Antarctica in Sabrina Coast area 

 (120^E). (After Jivago and Lissitzin, 1957.) 



shallowor and narrower channels of similar trend have been foinid between 

 the mainland and it (Fig. 3). In northern Europe, a deej) marginal channel is 

 found in the Skagerrak close to the Norwegian coast : the deepest part lies to 

 the east at the entrance of the Kattegat, and here reaches more than 350 fm. 

 Farther north, off Norway, marginal depressions deeper than the outer shelf 

 are also frequent, especially off More and Romsdal provinces (Fig. 4). Off 

 Labrador, a longitudinal channel runs parallel to the coast for more than 250 

 nautical miles, with de])ths of 300-400 fm, inside a shallower outer shelf; 

 another smaller channel is found to the north of Belle Isle. Although the 



