Identification_Information:
  Citation:
    Citation_Information:
      Originator: Bradford Butman
      Originator: Page C. Valentine
      Originator: William W. Danforth
      Publication_Date: 2007
      Title: MB_BACKPC20M.TIF - 20-m resolution image of shaded relief multibeam bathymetry in Massachusetts Bay, pseudocolored by backscatter intensity
      Edition: 1.0
      Geospatial_Data_Presentation_Form: remote-sensing image
      Series_Information:
        Series_Name: Data Series
        Issue_Identification: 99
      Publication_Information:
        Publication_Place: Woods Hole Science Center, Woods Hole, MA
        Publisher: U.S. Geological Survey, Coastal and Marine Geology Program
      Online_Linkage: http://pubs.usgs.gov/ds/99/massbay_gis/2_multibeam/imagery/mb_backpc20m.zip
      Online_Linkage: http://pubs.usgs.gov/ds/99/webpages/massbay.html
      Larger_Work_Citation:
        Citation_Information:
          Originator: Butman, Bradford
          Originator: Valentine, Page C.
          Originator: Middleton, Tammie J.
          Originator: Danforth, William W.
          Publication_Date: 2007
          Title: A GIS Library of Multibeam Data for Massachusetts Bay and the Stellwagen Bank National Marine Sanctuary, Offshore of Boston, Massachusetts
          Edition: 1.0
          Series_Information:
            Series_Name: Data Series
            Issue_Identification: 99
          Publication_Information:
            Publication_Place: Woods Hole Science Center, Woods Hole, MA
            Publisher: U.S. Geological Survey, Coastal and Marine Geology Program
          Online_Linkage: http://pubs.usgs.gov/ds/99/
  Description:
    Abstract:
      The U.S. Geological Survey has conducted geologic mapping to characterize the sea floor offshore of Massachusetts.  The mapping was carried out using a Simrad Subsea EM 1000 Multibeam Echo Sounder on the Frederick G. Creed on four cruises conducted between 1994 and 1998.  The mapping was conducted in cooperation with the National Oceanic and Atmospheric Administration (NOAA) and with support from the Canadian Hydrographic Service and the University of New Brunswick. 
       
      The long-term goal of this mapping effort is to produce high-resolution geologic maps and a Geographic Information System (GIS) project that presents images and grids of bathymetry, shaded relief bathymetry, and backscatter intensity data from these surveys that will serve the needs of research, management and the public.
    Purpose: This GeoTIFF (Tagged Image File Format) image shows shaded-relief multibeam bathymetry, pseudo-colored by backscatter intensity, in Massachusetts Bay at 20-m resolution.
  Time_Period_of_Content:
    Time_Period_Information:
      Range_of_Dates/Times:
        Beginning_Date: 1994
        Ending_Date: 1998
    Currentness_Reference: ground condition
  Status:
    Progress: Complete
    Maintenance_and_Update_Frequency: None planned
  Spatial_Domain:
    Bounding_Coordinates:
      West_Bounding_Coordinate: -70.788907
      East_Bounding_Coordinate: -70.599983
      North_Bounding_Coordinate: 42.322212
      South_Bounding_Coordinate: 42.203333
  Keywords:
    Theme:
      Theme_Keyword_Thesaurus: ISO 19115 Topic Category
      Theme_Keyword: oceans
      Theme_Keyword: oceans and estuaries
      Theme_Keyword: oceans and coastal
      Theme_Keyword: geoscientificInformation
      Theme_Keyword: imageryBaseMapsEarthCover
      Theme_Keyword: elevation
    Theme:
      Theme_Keyword_Thesaurus: General
      Theme_Keyword: backscatter intensity
      Theme_Keyword: pseudo-colored
      Theme_Keyword: multibeam
      Theme_Keyword: image
      Theme_Keyword: GeoTIFF
      Theme_Keyword: 20-m resolution
      Theme_Keyword: sea floor
      Theme_Keyword: sea floor mapping
      Theme_Keyword: USGS Map I-2734
      Theme_Keyword: Simrad
      Theme_Keyword: EM 1000
      Theme_Keyword: Frederick G. Creed
      Theme_Keyword: Woods Hole Science Center
      Theme_Keyword: WHSC
      Theme_Keyword: Coastal and Marine Geology Program
      Theme_Keyword: CMGP
      Theme_Keyword: U.S. Geological Survey
      Theme_Keyword: USGS
    Place:
      Place_Keyword_Thesaurus: General
      Place_Keyword: Massachusetts
      Place_Keyword: Massachusetts Bay
      Place_Keyword: Boston
      Place_Keyword: Gloucester
      Place_Keyword: Stellwagen Basin
      Place_Keyword: Stellwagen Bank
      Place_Keyword: Stellwagen Bank National Marine Sanctuary
      Place_Keyword: SBNMS
      Place_Keyword: Jeffreys Ledge
      Place_Keyword: MWRA ocean outfall
      Place_Keyword: MWRA
      Place_Keyword: Massachusetts Bay Disposal Site
      Place_Keyword: MBDS
      Place_Keyword: Tillies Bank
      Place_Keyword: Race Point Channel
      Place_Keyword: Gulf of Maine
      Place_Keyword: United States
      Place_Keyword: North Atlantic Ocean
  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.
  Point_of_Contact:
    Contact_Information:
      Contact_Organization_Primary:
        Contact_Organization: U.S. Geological Survey
        Contact_Person: Bradford Butman
      Contact_Position: Oceanographer
      Contact_Address:
        Address_Type: mailing and physical address
        Address: 384 Woods Hole Rd
        City: Woods Hole
        State_or_Province: MA
        Postal_Code: 02543-1598
        Country: USA
      Contact_Voice_Telephone: (508) 548-8700 x2212
      Contact_Facsimile_Telephone: (508) 457-2309
      Contact_Electronic_Mail_Address: bbutman@usgs.gov
      Hours_of_Service: 8 a.m. - 5 p.m.
  Native_Data_Set_Environment: Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.1.0.780
Data_Quality_Information:
  Attribute_Accuracy:
    Attribute_Accuracy_Report: No attributes are associated with these data.
  Logical_Consistency_Report: These data are logically consistent.
  Completeness_Report: These data are complete. No further processing and/or modifications will be made to these data.
  Positional_Accuracy:
    Horizontal_Positional_Accuracy:
      Horizontal_Positional_Accuracy_Report: These data were navigated with a Differential Global Positioning System (DGPS); they are accurate to +/- 3 meters, horizontally.
    Vertical_Positional_Accuracy:
      Vertical_Positional_Accuracy_Report: These data have been corrected for vessel motion (roll, pitch, heave, yaw) and tidal offsets, and referenced to mean lower low water.  The theoretical vertical resolution of the Simrad EM-1000 multibeam echosounder is 1 % of water depth; roughly 30 - 50 cm within the study area. However, we found that the working vertical resolution of the system is roughly +/- 50 cm for water depths of 30 - 50 meters based on comparisons of grids from multi-year surveys of the same area.
  Lineage:
    Source_Information:
      Source_Citation:
        Citation_Information:
          Originator: U.S. Geological Survey
          Publication_Date: Unpublished Material
          Title: Multibeam bathymetric survey data collected by USGS in Massachusetts Bay, 1994-1998
      Source_Time_Period_of_Content:
        Time_Period_Information:
          Range_of_Dates/Times:
            Beginning_Date: 1994
            Ending_Date: 1998
        Source_Currentness_Reference: ground condition
    Process_Step:
      Process_Description:
        A suite of processing software (called SwathEd) (www.omg.unb.ca/~jhc/SwathEd.html), developed by the Ocean Mapping Group at the University of New Brunswick (UNB), Canada, 
        was used to process and grid the multibeam bathymetric soundings and backscatter intensity data, and to produce images.  The metadata for the grids describes the processing steps applied to the navigation and bathymetric soundings.  The following processing steps produced the shaded relief image of bathymetry, colored by backscatter intensity: 

        1.  Create backscatter files that can be then mosaicked from the backscatter time series:

        Command line:  getBeamPattern filename (prefix only)
        Command line:  makess -pixel 3.0 -beam_patt beampatt filename (prefix only) output.ss
        Command line:  glfill output.ss output.ss_fill  (fills in data dropouts).

        2.  Mosaic all the backscatter files created in the last step (for each output.ss_fill), and then use a two point linear contrast stretch to enhance the backscatter image.

        Command line:  mos2 -autoseam -maxazi 10 -maxdist 10 mosaic_file output.ss_fill
        Command line:  stretchacres -low 180 -high 220 -in mosaic_file -out mosaic_file.stretch

        3.  Create a shaded relief image of the bathymetry using SwathEd routine addSUN (sun elevation of 45 degrees from 350, vertically exaggerating 4 times).  

        Command line:  addSUN -elev 45 -azi350 -vert_exag 4.0 gridFile.r4 filename.shade

        4.  Use a two point linear contrast stretch to enhance the shaded relief image:

        Command line:  stretchacres -low 150 -high 200 -in filename.shade -out filename_shade.stretch

        5. Create an image of shaded-relief topography, colored by backscatter intensity:

        Command line:  mix_ci -c mosaic_file.stretch -i filename_shade.stretch -m mosaic_file.pseudo

        6.  Create a tiff from the psuedocolored backscatter mosaic file using the netpbm utilities (http://netpbm.sourceforge.net/):

        Command line:  rawtopgm -headerskip 1024 image_width image_height mosaic_file.pseudo | pnmtotiff -none - > mosaic_pseudo.tif

        7.  Create an ESRI world file (tfw) for the pseudocolored backscatter intensity image for import to ArcView or ArcGIS.  Copy bounding box and resolution information from the jview program output to the .tfw file.

        Command line:  jview mosaic_file.pseudo
      Process_Date: Unknown
      Process_Contact:
        Contact_Information:
          Contact_Person_Primary:
            Contact_Person: William Danforth
            Contact_Organization: U.S. Geological Survey
          Contact_Position: Operational Geologist
          Contact_Address:
            Address_Type: mailing and physical address
            Address: 384 Woods Hole Road
            City: Woods Hole
            State_or_Province: MA
            Postal_Code: 02543-1598
            Country: USA
          Contact_Voice_Telephone: (508) 548-8700 x2274
          Contact_Facsimile_Telephone: (508) 457-2310
          Contact_Electronic_Mail_Address: bdanforth@usgs.gov
          Hours_of_Service: 8 a.m. to 5 p.m. EST
    Process_Step:
      Process_Description:
        Reprocessing to correct projection error

        An error in the UNB processing software that resulted in the multibeam observations not being properly projected onto a plane was discovered in 2003.  These software errors were corrected and the data re-gridded.  The images of pseudocolored backscatter intensity in the Stellwagen Bank region presented here may differ from preliminary versions included in the following publications:

        Butman, B., and Lindsay, J.A. (Eds.), 1999, A marine GIS Library for Massachusetts Bay: focusing on Disposal sites, Contaminated Sediments, and Sea Floor Mapping: U.S. Geological Survey Open-File Report 99-439, 1 CD-ROM. (Also available on line at http://pubs.usgs.gov/of/of99-439/start.htm)

        Gutierrez, B.T., Butman, Bradford, and Blackwood, D.S., 2001, Photographs of the sea floor of western Massachusetts Bay, offshore of Boston, Massachusetts, July 1999: U.S. Geological Survey Open-File Report 00-427, 1 CD-ROM. (Also available on line at http://pubs.usgs.gov/of/of00-427/)

        Valentine, P.C., Middleton, T., and Fuller, S., 2001, Maps showing sea floor topography, sun-illuminated sea floor topography, and backscatter intensity of the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts: USGS Open-File Report #00-410, 1 CD-ROM, scale 1:60,000. (Also available on line at http://pubs.usgs.gov/of/of00-410/)
      Process_Date: Unknown
      Process_Contact:
        Contact_Information:
          Contact_Person_Primary:
            Contact_Person: William Danforth
            Contact_Organization: U.S. Geological Survey
          Contact_Position: Operational Geologist
          Contact_Address:
            Address_Type: mailing and physical address
            Address: 384 Woods Hole Road
            City: Woods Hole
            State_or_Province: MA
            Postal_Code: 02543-1598
            Country: USA
          Contact_Voice_Telephone: (508) 548-8700 x2274
          Contact_Facsimile_Telephone: (508) 457-2310
          Contact_Electronic_Mail_Address: bdanforth@usgs.gov
          Hours_of_Service: 8 a.m. to 5 p.m. EST
    Process_Step:
      Process_Description: Image shifted 1/2 grid cell to northwest (using the ArcMap/Data Management Tools/Projections and Transformations/Raster/Shift tool) to correct for an error identified in the SwathEd gridding algorithm in 2007.  World files corrected.
      Process_Date: 200702
      Source_Produced_Citation_Abbreviation: mb_backpc20m.tif
      Source_Produced_Citation_Abbreviation: mb_backpc20m.tfw
      Process_Contact:
        Contact_Information:
          Contact_Person_Primary:
            Contact_Person: William Danforth
            Contact_Organization: U.S. Geological Survey
          Contact_Position: Operational Geologist
          Contact_Address:
            Address_Type: mailing and physical address
            Address: 384 Woods Hole Road
            City: Woods Hole
            State_or_Province: MA
            Postal_Code: 02543-1598
            Country: USA
          Contact_Voice_Telephone: (508) 548-8700 x2274
          Contact_Facsimile_Telephone: (508) 457-2310
          Contact_Electronic_Mail_Address: bdanforth@usgs.gov
Spatial_Data_Organization_Information:
  Direct_Spatial_Reference_Method: Raster
  Raster_Object_Information:
    Raster_Object_Type: Pixel
    Row_Count: 4030
    Column_Count: 3610
    Vertical_Count: 1
Spatial_Reference_Information:
  Horizontal_Coordinate_System_Definition:
    Planar:
      Map_Projection:
        Map_Projection_Name: Mercator
        Mercator:
          Standard_Parallel: 41.650000
          Longitude_of_Central_Meridian: -70.316667
          False_Easting: 0.000000
          False_Northing: 0.000000
      Planar_Coordinate_Information:
        Planar_Coordinate_Encoding_Method: row and column
        Coordinate_Representation:
          Abscissa_Resolution: 20.000000
          Ordinate_Resolution: 20.000000
        Planar_Distance_Units: meters
    Geodetic_Model:
      Horizontal_Datum_Name: North American Datum of 1983
      Ellipsoid_Name: Geodetic Reference System 80
      Semi-major_Axis: 6378137.000000
      Denominator_of_Flattening_Ratio: 298.257222
  Vertical_Coordinate_System_Definition:
    Depth_System_Definition:
      Depth_Datum_Name: Mean lower low water
      Depth_Resolution: 0.5
      Depth_Distance_Units: Meters
      Depth_Encoding_Method: Explicit depth coordinate included with horizontal coordinates
Entity_and_Attribute_Information:
  Detailed_Description:
    Entity_Type:
      Entity_Type_Label: Band_1
    Attribute:
      Attribute_Label: ObjectID
      Attribute_Definition: Internal feature number.
      Attribute_Definition_Source: ESRI
      Attribute_Domain_Values:
        Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated.
    Attribute:
      Attribute_Label: Value
    Attribute:
      Attribute_Label: Red
    Attribute:
      Attribute_Label: Green
    Attribute:
      Attribute_Label: Blue
    Attribute:
      Attribute_Label: Count
  Overview_Description:
Distribution_Information:
  Distributor:
    Contact_Information:
      Contact_Person_Primary:
        Contact_Person: Bradford Butman
        Contact_Organization: U.S. Geological Survey
      Contact_Position: Oceanographer
      Contact_Address:
        Address_Type: mailing and physical address
        Address: 384 Woods Hole Road
        City: Woods Hole
        State_or_Province: Massachusetts
        Postal_Code: 02543-1598
        Country: USA
      Contact_Voice_Telephone: (508) 548-8700 x2212
      Contact_Facsimile_Telephone: (508) 457-2309
      Contact_Electronic_Mail_Address: bbutman@usgs.gov
      Hours_of_Service: 8 a.m. to 5 p.m. EST
  Resource_Description: Downloadable Data
  Distribution_Liability:
    Although these data have been used by the U.S. Geological Survey (USGS), U.S. Department of the Interior (DOI), no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. 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.
  Standard_Order_Process:
    Digital_Form:
      Digital_Transfer_Information:
        Format_Name: TIFF
        Format_Specification: GeoTIFF
        Format_Information_Content: A zip archive containing the GeoTIFF image, associated world file, and metadata.
        File_Decompression_Technique: zip archive
        Transfer_Size: 0.000
      Digital_Transfer_Option:
        Online_Option:
          Computer_Contact_Information:
            Network_Address:
              Network_Resource_Name: http://pubs.usgs.gov/ds/99/massbay_gis/2_multibeam/imagery/mb_backpc20m.zip
          Access_Instructions: Data may be downloaded via the World Wide Web.
        Offline_Option:
          Offline_Media: DVD-ROM
          Recording_Capacity:
            Recording_Density: 4.75
            Recording_Density_Units: Gbytes
          Recording_Format: UDF
    Fees: None
  Technical_Prerequisites: 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.
Distribution_Information:
  Distributor:
    Contact_Information:
      Contact_Organization_Primary:
        Contact_Organization: U.S. Geological Survey Information Services
      Contact_Address:
        Address_Type: mailing address
        Address: Box 25286 Denver Federal Center
        City: Denver
        State_or_Province: Colorado
        Postal_Code: 80225-0046
        Country: USA
      Contact_Voice_Telephone: (303) 202-4700
      Contact_Facsimile_Telephone: (303) 202-4188
      Hours_of_Service: 8 a.m. to 5 p.m. Mountain Time
  Resource_Description: Downloadable Data
  Distribution_Liability:
    Although these data have been used by the U.S. Geological Survey (USGS), U.S. Department of the Interior (DOI), no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. 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.
  Standard_Order_Process:
    Digital_Form:
      Digital_Transfer_Information:
        Format_Name: TIFF
        Format_Specification: GeoTIFF
        Format_Information_Content: A zip archive containing the GeoTIFF image, associated world file, and metadata.
        File_Decompression_Technique: zip archive
        Transfer_Size: 0.000
      Digital_Transfer_Option:
        Offline_Option:
          Offline_Media: DVD-ROM
          Recording_Capacity:
            Recording_Density: 4.75
            Recording_Density_Units: Gbytes
          Recording_Format: UDF
    Fees: None
  Technical_Prerequisites: 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.
Metadata_Reference_Information:
  Metadata_Date: 20070328
  Metadata_Contact:
    Contact_Information:
      Contact_Person_Primary:
        Contact_Person: Bradford Butman
        Contact_Organization: U.S. Geological Survey
      Contact_Position: Oceanographer
      Contact_Address:
        Address_Type: mailing and physical address
        Address: 384 Woods Hole Road
        City: Woods Hole
        State_or_Province: MA
        Postal_Code: 02543-1598
        Country: USA
      Contact_Voice_Telephone: (508) 548-8700 x2212
      Contact_Facsimile_Telephone: (508) 457-2310
      Contact_Electronic_Mail_Address: bbutman@usgs.gov
  Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
  Metadata_Standard_Version: FGDC-STD-001-1998
  Metadata_Time_Convention: local time
  Metadata_Access_Constraints: None
  Metadata_Use_Constraints: None
  Metadata_Extensions:
    Online_Linkage: http://www.esri.com/metadata/esriprof80.html
    Profile_Name: ESRI Metadata Profile
