More information about this field activity and the data collected can be found at the Field Activity Web Page (<http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2011-005-FA>)
U.S. Geological Survey, 2014, FI_SONAR_5M: 5-meter per pixel acoustic backscatter mosaic collected by the U.S. Geological Survey offshore of Fire Island, NY in 2011 (UTM Zone 18N, WGS 84, GeoTIFF): Open-File Report 2014-1203, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts.This is part of the following larger work.Online Links:
- <https://pubs.usgs.gov/of/2014/1203/GIS/sonar/fi_sonar.zip>
- <https://pubs.usgs.gov/of/2014/1203/html/ofr2014-1203-data_catalog.html>
Schwab, William C. , Denny, Jane F. , and Baldwin, Wayne E. , 2014, Maps Showing Bathymetry and Modern Sediment Thickness on the Inner- Continental Shelf Offshore of Fire Island, New York: pre-Hurricane Sandy: Open-File Report 2014-1203, U.S. Geological Survey, Coastal and Marine Geology Program, Reston, VA.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 5.000000
Ordinates (y-coordinates) are specified to the nearest 5.000000
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.
508-548-8700 x 2311 (voice)
508-457-2310 (FAX)
jdenny@usgs.gov
This GeoTIFF represents approximately 2800 line kilometers of acoustic backscatter data collected in 2011. These data were collected using an interferometric sonar (Systems Engineering and Assessment Ltd. (SEA) SWATHplus-M (234 kHz)) by the U.S. Geological Survey during USGS survey 2011-005-FA. Acoustic backscatter data were used to define the surficial sediment distribution on the inner-continental shelf offshore of Fire Island, New York to help assess environmental change caused by natural processes and human activities.
U.S. Geological Survey, Unpublished Material, Raw Interferometric Data.
Sonar: Swath-bathymetric and acoustic-backscatter data were acquired with a SEA, Ltd., SWATHplus-M interferometric sonar operating at a frequency of 234 kHz and a variable range (increased or decreased manually depending on water depth). The system was operated with a transmit power: 80 percent, 4096 samples per channel, and a variable range (increased or decreased depending on water depth). The SWATHplus-M was mounted on the port side of the M/V Scarlett Isabella during survey operations. A Coda Octopus F180R Attitude and Positioning system recorded ship motion (heave, pitch, roll, and yaw). These data were transmitted via network connection to the SWATHplus-M acquisition software. The Octopus F180R Inertial Measurement Unit (IMU) was mounted directly above the SEA SWATHplus-M transducers, to minimize lever arm offsets that can lead to positioning errors. The F180R uses two L1 antennas for position and heading accuracy. The antennas are mounted on a rigid horizontal pole, positioned at the top of the sidemount, with a horizontal separation of 1 meter and are offset from the IMU in a forward/aft configuration. The forward offset of the primary antenna from the IMU is 0.5 meters, with no port/starboard offset.
Sound Velocity Profiles: 135 sound velocity profiles were acquired during survey operations at roughly 1 to 3 hour intervals using an Odim MVP30 motion vessel profiler. The MVP30 failed during survey operations. Sound velocity profiles were only collected during JD141 through 143 (lines 1 through 27).
While much effort was devoted to cleaning the data and minimizing survey artifacts, some artifacts may still be seen in the final GeoTIFF including an along track artifact at nadir (the ship track). These artifacts are especially noticeable in the shallow nearshore region of the survey.
More information about this field activity and the data collected can be found at the Field Activity Web Page (<http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2011-005-FA>)
Jane F. Denny performed this and all subsequent process steps.
Person who carried out this activity:
508-548-8700 x 2311 (voice)
508-457-2311 (FAX)
jdenny@usgs.gov
Schwab, William C. , Baldwin, Wayne E. , Hapke, Cheryl J. , Lentz, Erika E. , Gayes, Paul T. , Denny, Jane F. , List, Jeffrey H. , and Warner, John C. , 2013, Geologic Evidence for Onshore Sediment Transport from the Inner Continental Shelf: Fire Island, New York: Journal of Coastal Research Volume 29, Issue 3, pp. 526-544., Coastal Education and Research Foundation, Inc., Florida, USA.Online Links:
Foster, David S. , Swift, Ann B. , and Schwab, William C. , 1999, Stratigraphic Framework Maps of the nearshore area of southern Long Island from Fire Island to Montauk Point, NY: Open-File Report 99-559, U.S. Geological Survey, Reston, VA.Online Links:
Schwab, William C. , Thieler, E. Robert , Denny, Jane F. , Danforth, William W. , and Hill, Jenna C. , 2000, Seafloor sediment distribution off southern Long Island, New York: Open-File Report 00-243, U.S. Geological Survey, Reston, VA.Online Links:
There are no attributes associated with a GeoTIFF image. Image pixel values contain acoustic reflectivity values normalized to a 24-bit data range. Low-backscatter is represented by dark tones (low values) and high-backscatter is represented by bright tones (high values). The background color is set to 0-0-0 and can be turned off without removing data values.
Navigation was acquired with Differential Global Positioning System and Wide Area Augmentation System (DGPS+WAAS), which is accurate to + or - 1 to 2 meters, horizontally. The forward, or primary, Coda Octopus F180R Attitude and Positioning system antenna was used to acquire DGPS data and transmit via a network connection to the SEA SWATHplus data acquisition software. The F180R Attitude and Positioning system uses 2 L1 antennas for position and heading and an Inertial Measurement Unit (IMU) for motion sensing (heave, pitch, roll and yaw). The F180R IMU is mounted directly above the SEA SWATHplus-M transducers on the sidemount. The F180R antennas are mounted at the top of the sidemount offset in a forward/aft configuration. The offsets were applied within the SWATHplus and Coda Octopus F180R acquisition software.
Line 1 - 51, 61 - 64, 68 - 87, and 93 - 109 were used to generate the GeoTIFF image. Lines 52-60, 65 - 67, and 89 - 92 are tie lines collected orthogonal to the shoreline. Lines l27f5, l28f1, l28f2, l29f4, and l61f1 were not included in the mosaic, as the raw data files were not recorded. Tie lines were not incorporated in the GeoTIFF image.
This image represents interferometric acoustic backscatter data collected offshore of Fire Island, New York. Gaps generally occur along-track and between adjacent lines where complete coverage of the sea floor was not possible due to narrow swath widths. This primarily occurs in the shallowest regions of the survey.
Are there legal restrictions on access or use of the data?
- Access_Constraints: none
- Use_Constraints:
- 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 x 2311 (voice)
508-457-2311 (FAX)
jdenny@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: | This WinZip (version 14.0) file contains a GeoTIFF image of interferometric acoustic backscatter data collected offshore of Fire Island, NY. This also includes a TIFF World File (tfw) and associated metadata. in format GeoTIFF (version 1.0) GeoTIFF Format (Georeferenced TIFF Image) Size: 10.6 MB |
|---|---|
| Network links: |
<https://pubs.usgs.gov/of/2014/1203/GIS/sonar/fi_sonar.zip> <https://pubs.usgs.gov/of/2014/1203/html/ofr2014-1203-data_catalog.html> |
none
This zip file contains a GeoTIFF image with an accompanying world file. To utilize these data, the user must have an image viewer, image processing or GIS software package capable of importing a GeoTIFF image. A free spatial data viewer, ArcGIS Explorer, capable of displaying the data is available from Esri at www.esri.com. The zip file also contains associated metadata.
508-548-8700 x 2311 (voice)
508-457-2311 (FAX)
jdenny@usgs.gov
