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Bogue Sound, NC (S030) Bathymetric Digital Elevation Model (30 meter resolution) Derived From Source Hydrographic Survey Soundings Collected by NOAA
Bathymetry for Bogue Sound was derived from eleven surveys containing 52,366 soundings. Two older, overlapping, less accurate surveys were entirely omitted. The overlap from one older, less accurate survey was omitted before tinning the data. The average separation between soundings was 72 meters. Surveys dating from 1876 to 1953 covered the east and west portions of the sound. Surveys from 1974 covered the center portion of the sound. The total range of sounding data was 0.9 to -17.1 meters at mean low water. Mean high water values between 0.5 to 1.0 meters were assigned to the shoreline. One point that was not consistent with the surrounding data was removed prior to tinning. DEM grid values outside the shoreline (on land) were assigned null values (-32676). Bogue Sound has six 7.5 minute DEMs and two one degree DEMs. The 1 degree DEMs were generated from the higher resolution 7.5 minute DEMs which covered the estuary. A Digital Elevation Model (DEM) contains a series of elevations ordered from south to north with the order of the columns from west to east. The DEM is formatted as one ASCII header record (A- record), followed by a series of profile records (B- records) each of which include a short B-record header followed by a series of ASCII integer elevations (typically in units of 1 centimeter) per each profile. The last physical record of the DEM is an accuracy record (C-record). The 7.5-minute DEM (30- by 30-m data spacing) is cast on the Universal Transverse Mercator (UTM) projection. It provides coverage in 7.5- by 7.5-minute blocks. Each product provides the same coverage as a standard USGS 7.5-minute quadrangle but the DEM contains over edge data. Coverage is available for many estuaries of the contiguous United States but is not complete.