usSEABED Data Format and ContentusSEABED is linked to the original data through the source file:
Textural and other basic informationTextural, statistical, geochemical, geophysical, dominant component and color information are held in three separate, but similar, data files, based on the type of data:
The three data file types have the same fields and can be combined for more extensive coverage of the seafloor. Data users should see discussions in the data publications that delineate the differences and limitations of these three files. Component/feature and facies dataTwo data files contain mined numeric values from word-based data about presence of certain compositional content (i.e., quartz, andesite, benthic foramifera, nodules, etc.) seafloor features (i.e., ripples, bioturbation, worm tubes), biota, and sediment structure. These data represent the types of data most recorded in reports (i.e., presence). The dbSEABED program acts on, and usSEABED data files record, only data that are noted by the original researcher. That is, many other instances of 'shells', 'bioturbation', 'kelp', 'coral', or 'brittlestar' undoubtedly exist on the seabed; but, if the original researcher was not interested and did not note them, this process cannot assess them. Users of these data should be aware that only relative presence of components and features can be suggested; absence should not be assumed.
As with the parsed data files, the values held within the _CMP and _FAC files are the results of filters based on fuzzy set membership to chosen sets, and represent a measure of truth about the attribute, not a percentage or defined values. An additional output file type, although unpublished, provides quality control for the data and is used extensively prior to publication to debug and test the data. |
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U.S. Department of the Interior U.S. Geological Survey Western Coastal & Marine Geology
URL: http://walrus.wr.usgs.gov/usseabed/content.html
Project coordinators: J.A. Reid and S.J. Williams
Maintained by: Laura Zink Torresan
Last Modified: 28 August 2006 (lzt)