In other parts of the AEC marine sciences program indirectly related 

 to coastal engineering work, studies are supported which concern the chem- 

 istry and radiochemistry of particulate material and material in solution 

 in the oceans. Some of this involves trace elements. Other studies are 

 concerned with geochronology, i, e. , determining the age of sediments through 

 the known decay rates of certain natural heavy element radioisotopes. 



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