CONCLUSIONS 



Microrelief is related to, and directly influenced by, 

 volcanism, earthquakes, mass water movements, depth of 

 water, chemistry of seawater, sediment accumulation, 

 turbidity flows, atmospheric fallout, subaerial runoff, 

 biological activities, geographical location, and inter- 

 mediate and major underwater relief features. Microrelief 

 is not confined to visible microstructures at the interface 

 but also occurs as subsurface internal structures of varied 

 origin,, The importance of microrelief is only now being 

 recognized because of its effect on underwater sound 

 transmission. 



Microrelief will have a bearing on the future con- 

 struction of underwater launching pads, roads, industrial 

 plants, towers, transducer platforms, dwellings, and 

 farming areas, as well as on methods of waste disposal 

 and on the underwater movements of submersibles and 

 tracked vehicles. 



Patterns of microrelief over thousands of square 

 miles of sea floor are being recognized. From many 

 photographic samplings and target measurements, a 

 numerical scale of sea floor microroughness has been 

 established that should prove useful for acoustic purposes. 



Zones of equal sea floor roughness and general 

 similarities have been delineated in parts of the Pacific, 

 Indian, and Arctic Oceans. Because of the existence of 

 multitudes of localized smaller features, it is impossible 

 to show microrelief in its entirety on the small-scale 

 charts normally employed. The average values that are 

 shown should, however, permit predictions to be made to 

 assist in the solving of acoustic problems. * 



* Stereophotographic studies of sea floor roughness now in 

 progress will provide greater resolution of microslopes. 



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