SECT. 2] 



ABYSSAL PLAINS 



319 



b. Biscay Abyssal Plain 



The Bay of Biscay is occupied by a plain of 30,000 mi^ extending both NW 

 and SW, where there appear to be connections with the Porcupine Plain and 

 with the Iberian Plain. The contours of the plain suggest that all the sediment 

 is derived from the part of the continental shelf running NW from Cap Breton 



Fig. 6. Abyssal plains east of the Mid-Atlantic Ridge, as far south as 24°N. Land, black ; 

 non -abyssal -plain areas, stippled. 



Canyon, bordering the coast of France, and the approaches to the English 

 Channel. Very little sediment has come from the north coast of Spain where 

 there are mountains close to the coast and the rivers are short. The deepest part 

 of the plain is in the SW corner where the gradient is about 1 : 2500 and the 

 depth is 2750 fm. In the extreme SW corner, channels in the plain converge on 



