596 CYCLES OF ORGANIC AND INORGANIC SUBSTANCES 



variance with the relative enrichment of the metals in marine 

 organisms. The animals and plants of the sea provide a huge 

 reaction area for the uptake of dissolved metallic ions. One 

 governing factor for the uptake of specific ions in competition 

 with other ions is the equilibrium constants of the chelating 

 reactions. 



Concepts in modern chemistry should pro\"ide an entry into 

 the resolution of the host of problems confronting the marine 

 chemist. Why, for example, do manganese nodules close to coastal 

 areas contain extremely high amounts of manganese compared to 

 iron? A nodule recently dredged from the Gulf of California con- 

 tained essentially pure AlnOo and was devoid of the normally 

 associated metals such as nickel, cobalt, zinc, and copper. 



What is the intimate chemistry in\-olved in the formation of 

 phosphorites and glauconites on the sea floor? What redox con- 

 ditions are required for their buildup and what associations with 

 the biochemistry of the seas, if any, are involved? 



The distinction between detrital and authigenic clay minerals is 

 not clear-cut, if it can ever be. It has been known since the early 

 thirties, after the work of Goldschmidt, that boron is enriched in 

 marine, compared to continental, clays. Marine sediments contain 

 hundreds of parts per million of boron whereas continental clays 

 contain but one-tenth to one-twentieth of this amount. The boron 

 Is strongly held in the clay lattice, not remo\'ed by various wash- 

 ing or chelating elements. Where does it sit in the clay lattice? 

 Boron, much more abundant in the oceans than in terrestrial 

 waters, may well enter the clay structure or additions to the 

 already existing minerals resulting in higher contents of this 

 element in marine clays. Any continental clays introduced into 

 the oceans would obtain their boron on the sea floor rather than 

 during their passage to the sea floor because of the much longer 

 time periods. The problem of detrital versus authigenic marine 

 clays in the extreme reverts to the classical conundrum of the 

 sock which is repeatedly darned until none of the original material 

 is left. Is this a new sock or not? A continental clay rearranges on 

 the sea floor. Is this a new clay or not? 



