447 



FUTURE DIRECTIONS IN OCEAN SCIENCES 



109 



Q. 

 Q 



.^S' 



Coastal I 

 Plain I 



Continental Shelf 





Continental Rise 



Abyssal 

 Plain 



_ 1 



E 2-1 



jz 3 



Q. . 



0) 4 



° 5H 



■OMMm^MMMMMftriMi 



Range t.5- 3.5 km -3 



Average 4 km 

 Vertlcai Exaggeration = 20x 



FIGURE 3-3 Typical profiles of two common types of continental mar- 

 gins. Upper panel: A collision margin typical of the Pacific coast of 

 South America. The presence of a submarine trench, a narrow continen- 

 tal shelf, and a landward mountain range characterize this type of mar- 

 gin. Lower panel: A trailing-edge margin typical of much of the Atlantic 

 Ocean. The presence of a continental rise, a broad continental shelf, and 

 a coastal plain are characteristic of this type of margin. 



Coast). The margins are often greatly modified by erosion and 

 sediment deposition, processes that tend to carve out submarine 

 canyons and fill in basins, respectively. 



The following sections describe processes that make the coastal 

 ocean unique and discuss some scientific issues that will be par- 

 ticularly important over the coming decade. Emphasis is on in- 

 terdisciplinary aspects because it is likely that most important 

 scientific and societal problems cannot be tackled successfully 

 without a comprehensive approach. . . 



