U.S. Geological Survey, 2007, MOSAIC - Composite Sidescan-Sonar Mosaic collected by the U.S. Geological Survey offshore of the Grand Strand, SC (1999 – 2003) (GeoTIFF): Open-File Report 2005-1346, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.This is part of the following larger work.Online Links:
Baldwin, W.E., Denny, J.F., Schwab, W.C., Gayes, P.T., Morton, R.A., and Driscoll, N.W., 2007, Geologic Framework Studies of South Carolina's Long Bay from Little River Inlet to Winyah Bay, 1999-2003; geospatial data release: Open-File Report 2005-1346, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.Online Links:
This is a Raster data set. It contains the following raster data types:
Planar coordinates are encoded using row and column
Abscissae (x-coordinates) are specified to the nearest 4.000000
Ordinates (y-coordinates) are specified to the nearest 4.000000
Planar coordinates are specified in meters
The horizontal datum used is D_WGS_1984.
The ellipsoid used is WGS_1984.
The semi-major axis of the ellipsoid used is 6378137.000000.
The flattening of the ellipsoid used is 1/298.257224.
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This data set contains the sidescan-sonar imagery collected offshore of the Grand Strand, SC 1999 - 2003. These data are used in conjunction with surficial sediment analyses to define the sediment distribution within the survey area.
Person who carried out this activity:
508-548-8700 x2311 (voice)
508-457-2310 (FAX)
jdenny@usgs.gov
These data measure the acoustic reflectivity of the seafloor. These values (Digital Number (DN)) are a relative measure of reflectivity within the study area and are internally consistent.
DGPS is assumed to be accurate within 1-2 meters. Standard GPS is assumed accurate within 5-10 meters. 99% of the positional data is DGPS. Unless noted, all GPS/DGPS data is referenced to WGS84 (NAD83). Slant-range distance is recorded between the sidescan-sonar tow vehicle and a sidemount rigged with an acoustic transponder. Offset between the sidemount and GPS antennae is measured. Basic trigonomic calculations use the slant-range offset to calculate a 'fish' (tow-vehicle) navigation. An assumption in these calculations is that the tow-vehicle is traveling directly behind the vessel; movement to port or starboard is not accounted for within 'fish' navigation. Thus, the horizontal accuracy of the sidescan-sonar tow-vehicle is 10 meters.
All sidescan-sonar data collected during USGS field efforts offshore of Myrtle Beach, SC 1999 – 2003 are included. Spurious data were removed during processing.
These are raster data; all sidescan-sonar data collected during USGS field efforts offshore of Myrtle Beach, SC 1999 – 2003 are included. Processing removed any spurious data.
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- Use_Constraints:
- The Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.
508-548-8700 (voice)
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Downloadable Data
Although all data have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and/or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Data format: | File contains sidescan-sonar imagery collected offshore of the Grand Strand, SC in format TIFF (version ArcGIS 9.0) GeoTIFF Size: 300 MB |
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Network links: |
<http://pubs.usgs.gov/of/2005/1346/arcgis/mosaic/mosaic.zip> |
Media you can order: |
DVD-ROM
(Density 4.75
Gbytes)
(format UDF)
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This image is available as a GeoTIFF image with an accompanying world file. To utilize this data, the user must have an image viewer, image processing or GIS software package capable of importing a GeoTIFF image.
508-548-8700 x2311 (voice)
508-457-2310 (FAX)
jdenny@usgs.gov