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Figure: Bathymetry of the coastal ocean offshore of the New York metropolitan region (bathymetry from National Oceanic and Atmospheric Administration Coastal Relief Model).
The sandy, relatively shallow mid-Atlantic continental shelf is incised by the Hudson Shelf Valley, the drainage channel for the Hudson River during a lower stand of sea level. The valley contains muddy sediments. A key research question addressed by the USGS studies is the role of the valley in sequestering and/or transporting sediments and associated pollutants.
relief image was created by vertically exaggerating the shelf topography 100 times and the land topography 15 times, and then artificially illuminating the relief by a light source positioned 45 degrees above the horizon from an azimuth of 350 degrees. In the resulting image, topographic features are enhanced by strong illumination on the northward-facing slopes and by shadows cast on southern slopes. The depth is coded by