BS_composite_10m.tif - 10-m backscatter mosaic produced from backscatter intensity data from sidescan sonar and multibeam datasets (GeoTIFF Image; UTM, Zone 19N, WGS 84)

Metadata also available as - [Outline] - [Parseable text] - [XML]

Frequently anticipated questions:

What does this data set describe?

Title:
BS_composite_10m.tif - 10-m backscatter mosaic produced from backscatter intensity data from sidescan sonar and multibeam datasets (GeoTIFF Image; UTM, Zone 19N, WGS 84)
Abstract:
These data are qualitatively derived interpretive polygon shapefiles and selected source raster data defining surficial geology, sediment type and distribution, and physiographic zones of the sea floor from Nahant to Northern Cape Cod Bay. Much of the geophysical data used to create the interpretive layers were collected under a cooperative agreement among the Massachusetts Office of Coastal Zone Management (CZM), the U.S. Geological Survey (USGS), Coastal and Marine Geology Program, the National Oceanic and Atmospheric Administration (NOAA), and the U.S. Army Corps of Engineers (USACE). Initiated in 2003, the primary objective of this program is to develop regional geologic framework information for the management of coastal and marine resources. Accurate data and maps of seafloor geology are important first steps toward protecting fish habitat, delineating marine resources, and assessing environmental changes because of natural or human effects. The project is focused on the inshore waters of coastal Massachusetts. Data collected during the mapping cooperative involving the USGS have been released in a series of USGS Open-File Reports (<http://woodshole.er.usgs.gov/project-pages/coastal_mass/html/current_map.html>). The interpretations released in this study are for an area extending from the southern tip of Nahant to Northern Cape Cod Bay, Massachusetts. A combination of geophysical and sample data including high resolution bathymetry and lidar, acoustic-backscatter intensity, seismic-reflection profiles, bottom photographs, and sediment samples are used to create the data interpretations. Most of the nearshore geophysical and sample data (including the bottom photographs) were collected during several cruises between 2000 and 2008. More information about the cruises and the data collected can be found at the Geologic Mapping of the Seafloor Offshore of Massachusetts Web page: <http://woodshole.er.usgs.gov/project-pages/coastal_mass/>.
  1. How should this data set be cited?

    Pendleton, Elizabeth, 2013, BS_composite_10m.tif - 10-m backscatter mosaic produced from backscatter intensity data from sidescan sonar and multibeam datasets (GeoTIFF Image; UTM, Zone 19N, WGS 84): Open-File Report 2012-1157, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    This is part of the following larger work.

    Pendleton, E.A., Baldwin, W.E., Barnhardt., W.A., Ackerman, S.D., Foster, D.S., Andrews, B.D., and Schwab, W.C., 2013, Shallow Geology, Seafloor Texture, and Physiographic Zones of the Inner Continental Shelf from Nahant to Northern Cape Cod Bay, Massachusetts: Open-File Report 2012-1157, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -71.081630
    East_Bounding_Coordinate: -69.916808
    North_Bounding_Coordinate: 42.894369
    South_Bounding_Coordinate: 41.920707

  3. What does it look like?

    <http://pubs.usgs.gov/of/2012/1157/GIS_catalog/SourceData/BS_browse.png> (PNG)
    Composite backscatter mosaic image

  4. Does the data set describe conditions during a particular time period?

    Beginning_Date: 01-Jan-1994
    Ending_Date: 07-May-2008
    Currentness_Reference: ground condition

  5. What is the general form of this data set?

    Geospatial_Data_Presentation_Form: remote-sensing image

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      This is a Raster data set. It contains the following raster data types:

      • Dimensions 10650 x 9400 x 1, type Pixel

    2. What coordinate system is used to represent geographic features?

      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:
      UTM_Zone_Number: 19
      Transverse_Mercator:
      Scale_Factor_at_Central_Meridian: 0.999600
      Longitude_of_Central_Meridian: -69.000000
      Latitude_of_Projection_Origin: 0.000000
      False_Easting: 500000.000000
      False_Northing: 0.000000

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 10
      Ordinates (y-coordinates) are specified to the nearest 10
      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.

  7. How does the data set describe geographic features?

    BS_composite_10m.tif.vat

    OID
    Internal feature number. (Source: ESRI)

    Sequential unique whole numbers that are automatically generated.

    VALUE

    COUNT

    Entity_and_Attribute_Overview:
    There are no attributes associated with this 16-bit GeoTIFF image. Image pixel values contain acoustic reflectivity values normalized to an 8-bit data range (0-255) with the data range 0-254 and 255 being no data. Although most of the small slivers and data gaps within the mosaic have a value of 254. Low-backscatter is represented by dark tones (low values) and high-backscatter is represented by bright tones (high values).
    Entity_and_Attribute_Detail_Citation: U.S. Geological Survey

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

  2. Who also contributed to the data set?

  3. To whom should users address questions about the data?

    Elizabeth A. Pendleton
    U.S. Geological Survey
    Geologist
    U.S. Geological Survey
    Woods Hole, MA 02543-1598
    USA

    508-548-8700 x2259 (voice)
    508-457-2310 (FAX)
    ependleton@usgs.gov

Why was the data set created?

This backscatter intensity mosaic was created as a single continuous image of the acoustic reflectivity of the sea floor from Salisbury Beach to Northern Cape Cod Bay. Generally, higher backscatter values (light tones) represent rock, boulders, cobbles, gravel, and coarse sand. Lower values (dark tones) usually represent fine sand and muddy sediment. These data in both this final form and at the input resolutions helped define the sediment texture and distribution maps presented as interpretive data layers in USGS OFR 2012-1157.

How was the data set created?

  1. From what previous works were the data drawn?

    Ackerman and others (2006) (source 1 of 7)
    Ackerman, S.D., Butman, B., Barnhardt, W.A., Danforth, W.W., and Crocker, J.M., 2006, High-resolution Geologic Mapping of the Inner Continental Shelf: Boston Harbor and Approaches, Massachusetts: Open-File Report 2006-1008, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    This report provided the source backscatter data for the Boston Harbor and approaches region. These geophysical data were acquired between 2000 and 2001 by NOAA aboard the Ship Whiting and its launches. An Edgetech 272-T and Klein T-5500 were used to acquire backscatter data.

    Andrews and others, 2010 (source 2 of 7)
    Andrews, B.D., Ackerman, S.D., Baldwin, W.E., and Barnhardt, W.A., 2010, Geophysical and Sampling Data from the Inner Continental Shelf: Northern Cape Cod Bay, Massachusetts: Open-File Report 2010-1006, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    This report provided the source backscatter for the Northern Cape Cod Bay region. These data were acquired between 2006 and 2008 by the USGS and CZM aboard the R/V Megan T. Miller and R/V Rafael. Backscatter data were acquired using a Klein 3000 dual-frequency sidescan-sonar, or an SEA SWATHplus interferometric sonar system.

    Barnhardt and others, 2010 (source 3 of 7)
    Barnhardt, W.A., Ackerman, S.D., Andrews, B.D., and Baldwin, W.E., 2010, Geophysical and Sampling Data from the Inner Continental Shelf: Duxbury to Hull, Massachusetts: Open-File Report 2009-1072, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    This report provided the source backscatter for the Duxbury to Hull, MA region. These data were acquired between 2006 and 2007 by the USGS, CZM, and NOAA aboard the R/V Megan T. Miller, R/V Rafael, and NOAA launches 1005 and 1014. USGS backscatter data were acquired using a Systems Engineering & Assessment, Ltd. (SEA) SWATHplus interferometric sonar system (234 or 117 kHz) or a Klein 3000 dual-frequency sidescan-sonar. NOAA backscatter data were acquired with a hull-mounted RESON SeaBat 3101 and 8125.

    Butman and others, 2007 (source 4 of 7)
    Butman, B., Valentine, P.C., Middleton, T.J., and Danforth, W.W., 2007, A GIS Library of Multibeam Data for Massachusetts Bay and the Stellwagen Bank National Marine Sanctuary, Offshore of Boston, Massachusetts: Digital Data Series 99, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    This report provided the source backscatter for the western Massachusetts Bay region including Stellwagen Bank. These data were acquired between 1994 and 1998 by the USGS, Canadian Hydrographic Survey, and University of New Brunswick aboard the Frederick G. Creed. Bathymetric and backscatter data were acquired using Simrad Subsea EM 1000 Multibeam Echo Sounder.

    Barnhardt and others, 2009 (source 5 of 7)
    Barnhardt, W.A., Andrews, B.D., Ackerman, S.D., Baldwin, W.E., and Hein, C.J., 2009, High-Resolution Geologic Mapping of the Inner Continental Shelf: Cape Ann to Salisbury Beach, Massachusetts: Open-File Report 2007-1373, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    This report provided the source backscatter for the Salisbury Beach to Cape Ann, MA region. These data were acquired between 2004 and 2005 by the USGS, CZM, and NOAA and Science Applications International Corporation (SAIC) aboard the R/V Ocean Explorer and the R/V Connecticut. USGS backscatter data were acquired using a Systems Engineering & Assessment, Ltd. (SEA) SWATHplus interferometric sonar system (234 or 117 kHz) and Klein 3000 dual-frequency sidescan-sonar. NOAA (SAIC) backscatter data were acquired with a hull-mounted RESON SeaBat 8101 (240 kHz).

    Barnhardt and others, 2006 (source 6 of 7)
    Barnhardt, W.A., Andrews, B.D., and Butman, B., 2006, High-Resolution Geologic Mapping of the Inner Continental Shelf: Nahant to Gloucester, Massachusetts: Open-File Report 2005-1293, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    This report provided the source backscatter for the Nahant to Gloucester, MA region. These data were acquired between 2003 and 2004 by the USGS and CZM, aboard the R/V Rafael. USGS backscatter data were acquired using a Edgetech DF1000 dual frequency sidescan sonar

    Poppe and othes, 2006 (source 7 of 7)
    Poppe, L.J., Paskevich, V.F., Butman, B., Ackerman, S.D., Danforth, W.W., Foster, D.S., and Blackwood, D.S, 2006, Geological Interpretation of Bathymetric and Backscatter Imagery: Open-File Report 2005-1048, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    This report provided the source backscatter for the Outer Cape Cod region including. These data were acquired between 1994 and 1998 by the USGS, Canadian Hydrographic Survey, and University of New Brunswick aboard the Frederick G. Creed. Bathymetric and backscatter data were acquired using Simrad Subsea EM 1000 Multibeam Echo Sounder.

  2. How were the data generated, processed, and modified?

    Date: 29-Mar-2012 (process 1 of 2)
    Each source backscatter mosaic image was brought into ArcMap version 9.3.1 and resampled using the ArcToolBox 'Resample' tool. 10-meters per pixel was chosen as the output resolution, which was the coarsest of any input, and 'nearest' was chosen as the resampling technique.

    Person who carried out this activity:

    Elizabeth A. Pendleton
    U.S. Geological Survey
    Geologist
    U.S. Geological Survey
    Woods Hole, MA 02543-1598
    USA

    508-548-8700 x2259 (voice)
    508-457-2310 (FAX)
    ependleton@usgs.gov

    Date: 01-Apr-2012 (process 2 of 2)
    Each of the resampled source backscatter images was brought into PCI Geomatic (version 10.1) and mosaicked together using the OrthoEngine tool 'Mosaic Only' with a blend width of 2 pixels and color matching turned on. No image registration was required since these images were published as georeferenced images. Once all of the source images were mosaicked into the composite mosaic, a GeoTIFF image was exported from PCI

    Person who carried out this activity:

    Elizabeth A. Pendleton
    U.S. Geological Survey
    Geologist
    U.S. Geological Survey
    Woods Hole, MA 02543-1598
    USA

    508-548-8700 x2259 (voice)
    508-457-2310 (FAX)
    ependleton@usgs.gov

  3. What similar or related data should the user be aware of?

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

    Image pixel values contain acoustic reflectivity values normalized to an 8-bit data range (0-255). Low-backscatter is represented by dark tones (low values) and high-backscatter is represented by bright tones (high values).

  2. How accurate are the geographic locations?

    In general, multibeam backscatter has a higher horizontal accuracy than sidescan sonar backscatter data, because there is no cable out or layback uncertainty associated with multibeam data. The horizontal accuracy of the multibeam backscatter (based on the accuracy listed in the input data) is assumed to be within 5 meters. The horizontal accuracy of sidescan sonar backscatter (also based on the accuracy reported in the input data reports) is assumed to be 10 meters. The mosaicking process in PCI used to combine all the source backscatter mosaics could introduce additional horizontal errors. This composite backscatter intensity mosaic is assumed to be horizontally accurate to within 50-meters, as additional errors could have been introduced during resampling, horizontal projections, and mosaicking within PCI.

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    This mosaic includes sidescan sonar and multibeam backscatter data collected during several cruises in the Gulf of Maine. The input mosaics can be viewed by visiting the websites listed in the Source Information. Not all of the sources used to create the bathymetry grid were used here for the backscatter mosaic. The image quality of the backscatter data from the NOAA hydrographic surveys and NOAA/UNH/SAIC survey was lower than desired.

  5. How consistent are the relationships among the observations, including topology?

    This backscatter mosaic was created from several smaller backscatter datasets that were processed and published as TIFF images (see Source Information for the individual input images). The only processing that was done to the source images was some color matching to make the individual images appear seamless. The individual source images are part of a larger mapping initiative: Gulf of Maine Mapping Initiative (GOMMI). The following website maintains a map that shows the extent of the high resolution surveys, the organizations that collected them, and a geographical name description of the area covered. <http://www.gulfofmaine.org/gommi/coverage-map.php> You can also download the source data listed in the source contribtutions from this page.

How can someone get a copy of the data set?

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 (USGS) as the source of this information.

  1. Who distributes the data set? (Distributor 1 of 1)

    Elizabeth A Pendleton
    U.S. Geological Survey
    Geologist
    U.S. Geological Survey
    Woods Hole, MA 02543-1598
    USA

    508-548-8700 x2259 (voice)
    508-457-2310 (FAX)
    ependleton@usgs.gov

  2. What's the catalog number I need to order this data set?

    Downloadable Data

  3. What legal disclaimers am I supposed to read?

    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 U.S. Geological Survey 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.

  4. How can I download or order the data?

  5. What hardware or software do I need in order to use the data set?

    This zip file contains a GeoTIFF image with a 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.

Who wrote the metadata?

Dates:
Last modified: 02-Jul-2013
Metadata author:
Elizabeth A. Pendleton
U.S. Geological Survey
Geologist
U.S. Geological Survey
Woods Hole, MA 02543-1598
USA

508-548-8700 x2259 (voice)
508-457-2310 (FAX)
ependleton@usgs.gov

Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)
Metadata extensions used:

Generated by mp version 2.9.21 on Tue Jul 02 13:39:56 2013