Data Specifications
- Area of Coverage: Coasts of the contiguous United States. Because these data have been collected for various independent studies, using many technologies, the density of sampling may vary across a given area.
- Date(s) Available: Range from the 1960s to the 2010s, depending on data type and geography. Archive is continually updated by local, state, and federal contributors.
- Format: ESRI Shapefile and ASCII comma-delimited text (.txt) file
- Resolution: Variable. Acoustic raster products, such as side-scan sonar mosaics, are comprehensive over an area at a given pixel resolution. Sediment grab samples have an observational unit less than 1 meter, and sampling density is variable.
- Minimal Mapping Unit: Variable depending on data set
- Accuracy: Variable. Generally no independent accuracy assessment was conducted, but data were collected and analyzed by skilled analysts using best practices, and an established quality control process was used.
Overview
usSEABED is a relational database containing over 300,000 site observations of seafloor sediment and physical character information for U.S. waters from the intertidal zone to the deep ocean, including rivers, lakes, and estuaries. These observations contain information on sediment texture, surface pattern, benthic biota, and seafloor geology. This information is useful for marine planning, ecological assessment, sea level change monitoring, and sediment movement analysis. Because many sites include direct observations, they also can be useful for validating maps derived from remote sensing methods. The data are recorded in a tabular format that can easily be imported into a traditional GIS environment.
