U.S. Geological Survey, 2011, tmunro_50m.asc - swath bathymetry collected by the U.S. Geological Survey offshore of the Gulf Islands, MS, 2010 (ESRI ASCII GRID): Open-File Report 2010-1178, 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:
Pendleton, Elizabeth A. , Baldwin, Wayne E. , Danforth, William W. , Dewitt, Nancy T. , Foster, David S. , Forde, Arnell S. , Kelso, Kyle W. , Pfeiffer, William R. , Turecek, Aaron M. , Flocks, James G. , and Twichell, David C. , 2011, Geophysical Data from offshore of the Gulf Islands from West Ship Island to Dog Key Pass, Mississippi: Open-File Report 2010-1178, 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 50.000000
Ordinates (y-coordinates) are specified to the nearest 50.000000
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.
(508) 548-8700x2266 (voice)
(508) 457-2310 (FAX)
dtwichell@usgs.gov
This grid represents approximately 270 square km of bathymetric data that were collected in 2010. These data are used to define the sea-floor morphology offshore of the Gulf Islands in Mississippi.
U.S. Geological Survey.
Person who carried out this activity:
(508) 548-8700x2259 (voice)
(508) 457-2310 (FAX)
ependleton@usgs.gov
Person who carried out this activity:
(508) 548-8700x2259 (voice)
(508) 457-2310 (FAX)
ependleton@usgs.gov
Person who carried out this activity:
(508) 548-8700 x2259 (voice)
(508) 457-2310 (FAX)
ependleton@usgs.gov
Person who carried out this activity:
(508)-548-8700 x2259 (voice)
(508)-457-2310 (FAX)
ependleton@usgs.gov
Person who carried out this activity:
(508)-548-8700 x2259 (voice)
(508)-457-2310 (FAX)
ependleton@usgs.gov
Huang, Lijuan, 20100226, NOAA/NOS Hydrographic Planning Team (HPT) tide zone model.Online Links:
Luis, J. F. , 2007, Mirone: A multi-purpose tool for exploring grid data.: 33, Computers and Geosciences.Online Links:
Wessel, P., and Smith, W.H.F., 1998, New, improved version of the Generic Mapping Tools released: EOS Transactions 79, American Geophysical Union.Online Links:
All attributes were checked in a consistent manner.
These data were navigated with a Differential Global Positioning System (DGPS); they are accurate to +/- 1 to 2 meters, horizontally. Unless noted, all DGPS data are referenced to WGS84, and distance between sidemounted interferometric sonar and GPS antennae are corrected.
The theoretical vertical resolution of the SEA Ltd SwathPlus interferometric sonar is 1 % of water depth, approximately 0.1 m within the study area. An Octopus F180 Attitude and Positioning system was used to correct for vessel roll, pitch, heave, and yaw during the first leg, 2010-012FA, whereas an Octopus F190 Attitude and Positioning system was used during the second leg, 10cct02. Tidal offsets were corrected with a NOAA tide zone model and referenced to mean lower low water (MLLW). Errors associated with the tidal zone model could be less than or equal to the tidal range for this area which is ~0.4 m. The gridding algorithm and cell size used on these data could introduce errors as great as 3 m along the edges of the Gulfport Ship Channel. Gridding-induced errors are likely much smaller (< 0.5 m) for most of the study area where slopes are less than 1 degree. Changes in ship draft due to water and fuel usage were not considered.
All shore parallel survey lines were incorporated. Tie (shore perpendicular) lines were not used in grid generation. The R/V Tommy Munro was contracted for the month of March 2010. The Woods Hole Science Center acquired data onboard between March 4 and March 17, 2010. Bathy data were acquired on 20100304-20100309; 20100311;20100315-20100317. Day gaps in acquisition were due to inclement weather or seismic tieline acquisition. The St. Petersburg Coastal and Marine Science Center acquired data onboard the R/V Tommy Munro between March 19 and March 29, 2010. Bathy data for this dataset were acquired on 201003019-20100320; 20100327-2010329. Day gaps in acquisition were due to inclement weather or data acquisition in another survey area.
Any spurious data points were removed during processing.
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) 548-8700x2259 (voice)
(508) 457-2310 (FAX)
ependleton@usgs.gov
Downloadable Data
Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. 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: | WinZip file containing an ESRI ASCII grid of swath bathymetric data collected offshore of the Gulf Islands, MS, and the associated metadata. in format WinZip (version 14.0) Size: 371 KB |
|---|---|
| Network links: |
<https://pubs.usgs.gov/of/2010/1178/GIS_catalog/Bathy/bathy_grd.zip> |
| Media you can order: |
DVD-ROM
(Density 4.75
Gbytes)
(format UDF)
|
The grid contained in the GIS_catalog.zip file is available as an ESRI binary grid. To utilize this data, the user must have a GIS software package capable of reading an ESRI binary grid. The grid contained in the bathy_grd.zip file is available as an ASCII grid with an ESRI header. To utilize this data, the user must have a GIS software package capable of reading ASCII grids with ESRI headers, or be able to manipulate an ASCII matrix with a geospatial header. The ASCII raster files can be easily converted to ESRI grid format in either ArcView with Spatial Analyst extension (Import Data Source: ASCII Raster) or ArcGIS with Spatial Analyst extension (ASCII to Raster). The user should select floating point grid (as opposed to integer grid) when converting the bathymetry data.
508-548-8700 x2259 (voice)
(508)-457-2310 (FAX)
ependleton@usgs.gov
