will continue to be one of the most exciting areas of research in the 

 coming years. Scientists are just beginning to understand how to 

 interpret the record revealed in sediments in terms of the 

 evolutionary history of the ocean basins and overlying water 

 columns. 



Resources of the Sea Floor 



A major project of NOAA's Atlantic Oceanographic and 

 Meteorological Laboratories in Miami is the study of the geological, 

 geophysical, and geochemical characteristics of a 3° corridor 

 between Cape Hatteras and Cape Blanc, northwest Africa. This strip 

 is continuous with the crustal section established across North 

 America by the U.S. Trans-Continental Geophysical Survey. The 

 purpose of the work is to provide, for the first time, a "standard 

 marine section" to which other oceanic geophysical activities may be 

 related. However, the project is also providing valuable information 

 about the ocean bottom that can be applied to the research for subsea 

 oil and minerals. 



Preliminary findings have already revealed the presence of 

 possible salt domes in the deep ocean basin off Cap Blanc, the first 

 region where possible salt domes have been identified in the deep 

 ocean basin. If true salt domes, their presence would suggest 

 substantial oil potential. Subsequently, other possible salt domes 

 have been identified at other sites in the Atlantic and South Atlantic 

 basins. Another recent accomplishment of this project was locating 

 the Trans-Atlantic Geotraverse (TAG) Hydrothermal Field, the first 

 hydrothermal mineral deposit (very pure manganese hydroxide, 

 discovered in the median valley of a midocean ridge). The deposit's 

 existence would suggest that oceanic crust that paves 2/3 of the earth 

 and is incorporated into certain islands and continents may be far 

 richer in minerals than previously suspected and point up the 

 importance of further studies of plate tectonics in relation to the 

 exploration for mineral deposits both on land and at sea. 



Perhaps the most exploitable resource of the deep-sea floor is the 

 iron-manganese concretions commonly referred to as manganese 

 nodules. These are found on the ocean floor in a number of areas in 

 the Pacific and Atlantic Oceans. Mineral companies are particularly 

 interested in their high copper, nickel, and cobalt content, partly 

 because of the diminished reserves of these ores under land surface 

 and partly because of the environmental damage caused by the 

 surface mining of low-grade ores. 



In an NSF program, scientists are trying to answer two major 

 questions about these strange nodules. The first is what processes 

 are responsible for the incorporation of exceptionally high concen- 

 trations of copper, nickel, and cobalt in nodules in certain limited 



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