for model generation. The collection of more complete areal ba thyme trie 

 surveys would allow further refinement of the models of sea-floor anlso- 

 tropy. FViture Improvements In deep-towed side-scan sonars and the col- 

 lection of additional bottom photographs would allow a quantitative 

 estimate to be made of the predictive ability of the model. 



The utility of the model falls Into two broad categories; engineer- 

 ing application and scientific Investigation. The application of the 

 model to underwater acoustics Is obvious. The model spectrum of the 

 surface relief Is an Important environmental factor In the scattering of 

 sound from the sea floor. Efforts are currently underway to develop 

 scattering models which utilize such stochastic environmental Informa- 

 tion. More traditional models require the description of the bottom as 

 a faceted surface, which can easily be derived from the derivative spec- 

 trum and a knowledge of the probability distribution of depths. Even 

 models requiring a fully determined surface can obtain a valid realiza- 

 tion by combining the model amplitude spectrum with a randomly generated 

 phase spectrum. 



In terms of scientific investigation, the method provides a new 

 tool for studying the earth's geological and tectonic processes. The 

 resulting patterns of roughness discovered on the Gorda Rise and Oregon 

 continental margin illustrate the ability of the method to detect inter- 

 esting relationships not obvious by simply studying bathymetrlc charts. 

 Comparing the distribution of roughness on a varied of spreading cen- 

 ters, continental margins and other submarine environments, should yield 

 valuable insight into the distribution of geologic processes on the sea 

 floor. In the case of the patterns on the Gorda Rise, the distribution 

 of roughness may well relate to the lava formation processes, which in 



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