Figure 15. Detailed planar view of the sun-illuminated bathymetry from the combined National Oceanic and Atmospheric Administration surveys in Rhode Island and Block Island Sounds showing obstacle marks in southwestern Block Island Sound. Note that the obstacle-mark and sand-wave asymmetries indicate net northwestward sediment transport. Location of view is shown in figure 11. Warmer colors denote shallower areas; cooler colors denote deeper areas. Depth key is shown in figure 9.