Welcome to usSEABED

usSEABED provides data on sediment and rock distributions in the waters off the United States.

Information about seafloor characteristics from the beach to the deep sea improves the understanding of interactions between land and sea, effects of river discharge and sea level changes, distributions of benthic flora and fauna, location and type of resources, potential consequences of human activities on the oceans, and other critical issues. Large- and small-scale maps of the seabed, as well as reliable data over broad geographical areas, allow for integrated insights into these issues and more.

To assist in addressing these issues, the USGS and the University of Colorado are creating usSEABED.  The datasets of usSEABED currently hold georeferenced point data for more than 300,000 data sites in U.S. waters from the beach to the deep sea, rivers, lakes, and estuaries. In usSEABED existing data from the USGS and other research groups are processed and extended to maximize their density and usability creating unified, comprehensive, relationally linked datasets for mapping and analysis.  Source data include surficial and subbottom data from physical sampling equipment (grabs and cores) and virtual sampling such as descriptions from seafloor photographs and videos.

The usSEABED database incorporates a wide variety of information about:

• Seafloor sediment texture, composition, and color,
• Biota and biological effects on the seafloor,
• Rocky areas and seafloor hardness,
• Seafloor features, such as ripples,
• Seafloor acoustic properties,
• Sediment geochemical analyses, and
• Sediment geotechnical analyses

The usSEABED files are produced as point locations held in comma-delimited text for ease of use in many software applications.

In addition to quantified lab-derived data, the datasets of usSEABED also include estimated numeric values for those typical seabed characteristics—noted above—based on the extensive accumulation of word-based data in U.S. waters. These data are rich in information, but were previously difficult to quantify, map, plot, or use in comparative analyses or models.

These descriptive data—from short sentences, small essays, or single phrases—are treated as a mathematical equation that is considered as a whole. Filters based on fuzzy set theory assign relative weight to each word in the description, and estimate the values of textural and other parameters. In addition, the textural implications of non-textural terms—such as 'broken shells' or Halimeda—are included in the calculation of grain-size parameters.

The resulting numeric data, now useable in a GIS or model, should be considered "fuzzy"; that is, they give an approximation—not a rigorous measurement—of the assessed values.

The data in usSEABED are in use by the U.S. Geological Survey and their collaborators in several projects along the contiguous U.S. Potential applications include benthic habitat analysis and maps of marine protected areas, marine aggregate assessments, sediment mobility, studies of the effects of anthropogenic activities, and Louisiana coastal ecosystem restoration. The data are also in use by University of Colorado and collaborators to study the movement of ripples along the seafloor, mine burial, and acoustic province mapping.

Other potential applications where data and maps from usSEABED might be useful are:

• Research ocean observatories and monitoring
• Coastal zone/ocean management and planning
• Homeland security, military applications
• Seafloor engineering planning and design
• Ocean disposal site placement, monitoring
• Cultural resources
• Seabed roughness, bedform distribution, critical shear stress, sediment transport flux
• Public education
• Seafloor bottom friction values for calibration of modeling processes, such as the effects of storm waves on sediment mobility and transport

Currently available to the public are data from the coasts of the contiguous 48 states (Atlantic margin, Gulf of Mexico and Caribbean margins, and Pacific margin). An upcoming publication will include Alaska and Hawaii.

To view published usSEABED data online, see the USGS ESRI® ArcIMS server. Data on this server is best viewed using (PC) Netscape Communicator™ version 4.51 or higher and Microsoft Internet Explorer™ versions 4 or higher web browsers, or (Macintosh) Netscape Communicator™ or Mozilla™ web browsers.*

Feedback on usSEABED is appreciated, both in usefulness and in error detection. Please use the contact information for questions and/or data to contribute to the growing usSEABED information system in the U.S. EEZ.

*Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government