slope toward the south-southeast Is very long wavelength and not 

 Included in the analysis. The small channels traversing the slope are 

 due presumably to downslope transport of sediment and represent an 

 apparent linear trend with wavelength o£ approximately 10-15 kilometers. 

 This is at the low frequency limit of the present analysis, but might 

 indicate such a trend in shorter wavelengths. Figure 6-9 graphically 

 illustrates the data set (in this case gridded at 0.1 minutes of lat- 

 itude and longitude), and shows this linear trend due to down-slope 

 processes. Coinciden tally, the survey track was run quasi-parallel to 

 this trend which could further complicate interpretation. 



The distribution of spectral parameters with azimuth are plotted in 

 Figure 6-10, in the same format as the previous plots. Notice again 

 that the parameter b(6) plotted above shows no functional relationship 

 Co azimuth 6, as predicted by theory. In this case, the mean value of 

 the b(6)'8 is -1.05. The intercept parameter a(6) reflects the rel- 

 atively smooth, isotropic nature of this sample of the sea floor. In 

 this ease, the mean amplitude of 0.097 meters is less than 61 of the 

 same parameter in the Gorda Rise area. The "anisotropy" term, v in this 

 case is estimated at 0.0063 meters, only IZ of the value for the Gorda 

 Rise. With these almost isotropic conditions, the estimate of the azi- 

 muth of maximum energy cannot be made with any fidelity. 



The final test area represents an inteinnediate level of both gen- 

 eral roughness and degree of anisotropy. The data were collected by the 

 SEAMARC-1 side-scan sonar system, which is a deep-towed instrument 

 developed by W.B.F. Ryan of Laraont-Doherty Geological Observatory. The 

 vehicle is towed at approximately 500 m above the sea floor and collects 

 data from side-scan sonar and from down-looking sonar. The depth of the 



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