Section IV., 1906. [ 67 ] Trans. R. S. C. 



VIII. — Features of the Continental SlieJf off Nova Scotia. 

 By H. S. Poole. 



(Read May 23, 1906.) 



Off the soutlierii shore of this Province much relating to the sea- 

 bottom ha.s been revealed by the investigations of the hydrographer, 

 and the operations of the cable laying companies. 



The information thus obtained together with that collected by 

 fishermen in the pursuit of their calling presents features that suggest 

 a consideration may well be given its structure closer than has yet been 

 bestowed on it. 



The present paper proposes to deal with the strip of submarine 

 ground that lies shoreward of the 80 fm. line running approximately 

 parallel to the coast at an average distance of about 100 miles off the 

 land. Close to this line the edge is mot of the marine terrace or plat- 

 form that projects seaward from under the east coast of the greater part 

 of the jSTorth American continent. The rapid drop into deep water 

 along the edge of this terrace or continental shelf is indicated on the 

 accompanying map by the contour lines which the soundings given on 

 Admiralty charts enable one to lay down. The edge thus defined ap- 

 pears as a fairly straight line with but few deflections indenting for 

 short distances towards the land that is in addition to the two ravines 

 of magnitude that sever the region and reach back to the coast. 



But had the soundings on which the position of this line has been 

 determined been taken much closer together than they have been, 

 especially along the margin, there is a probability the}'' would indicate 

 some such decided features as steep escarpments and possibly some 

 precipitous walls along the side of the platform with short ravines 

 oth(3r than those recognised serrating the edge and also exposing the re- 

 mains of fjords as 3'et but imperfectly silted up with later sediments. 

 In one respect our coast differs from the portion of the shelf south of 

 Cape Cod where its slope to the abyss is more gradual and where there 

 is off Hatteras a second terrace distinguished as the Blake plateau. 



In our section outside the 80 fm. line the soundings rapidly drop 

 into deep water, and a plunge to depths of 1000 fms. or more is made 

 within a further distance of 2 to 10 miles. 



It is particularly desired to note that along the Atlantic front of 

 the platform for the whole region lying off between Cape Sable and 

 Scaterie but two deep channels or fjords break the wall and extend 



