Figure 16. Image of sidescan-sonar data from National Oceanic and Atmospheric Administration (NOAA) survey H12023. Dark-shades are low backscatter and generally represent finer grained sediments and acoustic shadows; light-shades are high backscatter and generally represent coarser grained sediment and high acoustic reflectivity. Note that sidescan-sonar data were not collected in the entire survey area; stripes oriented along survey tracklines are artifacts of the data acquisition and processing and were not tonally matched.