NOAA/NOS and USCGS Seabed Descriptions from Hydrographic Surveys

The NOAA/NOS and USCGS Seabed Descriptions from Hydrographic Surveys database is a compilation of surficial sediment composition from multiple sources for over 200,000 seafloor sediment samples primarily around U.S. coastal areas. The descriptions were abstracted from unpublished data reports and Bottom Type "M" log sheets, and digitized from survey smooth sheets produced by the NOAA National Ocean Service (NOS) and its predecessor, the U.S. Coast and Geodetic Survey (USCGS). Prior to August 2001, many physical sediment samples were routinely sent to the Smithsonian Institution Museum of Natural History (NMNH) for archive with accompanying "M" log forms from which bottom type and other information were coded into the NMNH sediment database. In 2001, NMNH sent a copy of the database to NOAA's National Geophysical Data Center (now part of the National Centers for Environmental Information) to be incorporated into the Index to Marine and Lacustrine Geological Samples database, and for distribution to data users needing access to the bottom type information in the files. With support from NOS, NGDC digitized several thousand additional bottom type observations from historic NOS Hydrographic Survey smooth sheets and added them to the database. NOS is coding thousands more bottom type observations for entry into the database from survey Data Reports, or DRs. In 2011, NOS began adding standardized digital bottom type descriptions to the database using the International Hydrographic Organization (IHO) SF57 standard "NATSUR" (nature of surface) and "NATQUA" (nature of surface qualifier) coding scheme, transferring the data to NCEI in KML form for archive and upload to the geospatially-enabled database. Hydrographic Technical Directive (HTD)2011-6 contains the official new directive. Data are free for online search and download.