Open-File Report 2014-1040
Polygons of Global Undersea Features for Geographic Searches
The USGS shapefile of undersea features (undersea_features.shp) includes eight attributes (fig. 2), two of which are adopted from the GEOnet Names Server (GNS). These attributes are defined below. UFI Unique Feature Identifier (from GNS): a number that uniquely identifies the undersea feature (UF). A null value indicates that the feature is not listed in GNS (as noted in the COMMENTS attribute field). CENT_LAT Latitude of the UF centroid in decimal degrees: north latitudes are positive; south latitudes are negative. CENT_LONG Longitude of the UF centroid in decimal degrees: east longitudes are positive; west longitudes are negative. DSG Feature Designation Code (from GNS): a three- or four-character code that indicates the type of undersea feature represented (see United States Board on Geographic Names, 2005). A null value indicates that the feature is not listed in GNS (as noted in the COMMENTS attribute field). UF_NAME Name of the undersea feature, without diacritics: the BGN standard name is used (unless the feature is not listed in GNS, as noted in the COMMENTS attribute field).VAR_NAME This attribute field indicates any variant name used by GEBCO or USGS. COMMENTS The COMMENTS attribute field includes notes and abbreviated references recorded by the USGS project team. (Full references are provided in the formal metadata.) For some features, the notes include a depth range that was used to define the spatial extent. AREA_SQKM Area of the UF polygon: areas are given in square kilometers (as calculated in sinusoidal projection). |