Figure 4. A. Wegener's depiction of conti- 

 nental drift for three geologic periods. 

 Shaded area is ocean; dotted areas are shal- 

 low seas. Present-day outlines and rivers 

 are shown only for purposes of identifica- 

 tion. (A. Wegener, The Origins of Continents 

 and Oceans, trans, from the third German 

 edition, 1922) 



know what must be measured and where. One of 

 the fundamental puzzles of the planet appears 

 soluble. 



Much has been learned about the living crea- 

 tures of the ocean; comprehension of the dy- 

 namics of the food web of the seas is beginning, 

 but many blind spots remain. Scientists are puz- 

 zled about life in the deepest parts of the ocean. 

 They ask: how do animals living more than 2,000 

 meters under the sea sustain themselves? The 

 biomass there is only a miniscule fraction of that 

 in the shallow, Uluminated layers where the 

 world's fish are harvested. There may well be no 

 fish crops worth seeking at those depths. Yet, 

 about 84 per cent of the ocean floor Ues below 

 2,000 meters, and a large part of the total 

 nutrients in the ocean cycle through this zone. The 



Figure 5. Twenty tons of Pacific hake 

 (Meiluccius productus) caught by Bureau 

 of Commercial Fisheries research vessel 

 John N. Cobb in a one-hour midwater 

 trawl. (Bureau of Commercial Fisheries 

 photo) 



temperature is stable and cold; the tempo of life, a 

 crawl. There are no photosynthetic plants. The 

 supply of energy into the food web comes from 

 above. There is virtually no information on the 

 rate at which organic matter is delivered, or its 

 division for consumption among bacteria, bottom- 

 living animals or fish. If use of the deep ocean is 

 anticipated, it is necessary to build our under- 

 standing of the fundamental processes which occur 

 there. Will they be used for the disposition of 

 radioactive and human wastes? Will man be work- 

 ing and operating at such depths? At great depths, 

 plants and animals selectively concentrate radio- 

 active isotopes, they become food for other 

 animals which may go higher and in turn become 

 food for commercial fish. The meager store of 

 knowledge of this portion of the food web must 

 be materially increased. The capability to study in 

 these depths must be developed. 



Much has been learned of the chemistry of the 

 oceans, but major mysteries remain. 



The ocean is a 3.5 per cent salt solution contain- 

 ing all the known naturally occurring elements. 

 The major components and some of the minor 

 ones are present in constant proportions through- 

 out the world ocean. Despite the variable composi- 

 tion of streams feeding the ocean, the constancy is 

 maintained by chemical reactions in the sea, both 

 as the result of biological activity and interaction 

 with detrital material. These processes have not 

 yet been fully understood, although well thought- 

 out models have been proposed. Some of the trace 

 elements, including a few that are clearly funda- 

 mental to life processes, show variation with depth 

 and geography. The significance of these variations 



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