Identification_Information:
  Citation:
    Citation_Information:
      Originator: Bradford Butman
      Originator: William W. Danforth
      Publication_Date: 2007
      Title: Q2_SRELIEF.TIF - 6-m resolution gray-scale image of shaded-relief multibeam bathymetry in western Massachusetts Bay map Quadrangle 2
      Edition: 1.0
      Geospatial_Data_Presentation_Form: remote-sensing image
      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/q2_srelief.zip
      Online_Linkage: http://pubs.usgs.gov/ds/99/webpages/quad2.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
          Geospatial_Data_Presentation_Form: map, raster digital data, remote-sensing image, tabular digital data, vector digital data
          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 in western Massachusetts Bay map Quadrangle 2 as grayscale at 6-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: General
      Theme_Keyword: bathymetry
      Theme_Keyword: shaded-relief bathymetry
      Theme_Keyword: multibeam
      Theme_Keyword: image
      Theme_Keyword: GeoTIFF
      Theme_Keyword: 6-m resolution
      Theme_Keyword: sea floor
      Theme_Keyword: sea floor mapping
      Theme_Keyword: USGS Map I-2732
      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
    Theme:
      Theme_Keyword_Thesaurus: ISO 19115 Topic Category
      Theme_Keyword: oceans
      Theme_Keyword: oceans and estuaries
      Theme_Keyword: oceans and coastal
      Theme_Keyword: elevation
      Theme_Keyword: imageryBaseMapsEarthCover
    Place:
      Place_Keyword_Thesaurus: General
      Place_Keyword: Massachusetts Bay
      Place_Keyword: western Massachusetts Bay
      Place_Keyword: western Massachusetts Bay map Quadrangle 2
      Place_Keyword: Boston
      Place_Keyword: Massachusetts
      Place_Keyword: Stellwagen Basin
      Place_Keyword: MWRA ocean outfall
      Place_Keyword: MWRA
      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
  Cross_Reference:
    Citation_Information:
      Originator: Butman, Bradford
      Originator: Hayes, Laura
      Originator: Danforth, William W.
      Originator: Valentine, Page C.
      Publication_Date: 2003
      Title: Shaded relief and seafloor topography of Quadrangle 2 in western Massachusetts Bay offshore of Boston, Massachusetts
      Series_Information:
        Series_Name: Geologic Investigations Series Map
        Issue_Identification: I-2732-B
      Publication_Information:
        Publication_Place: Reston, VA
        Publisher: U.S. Geological Survey
      Online_Linkage: http://pubs.usgs.gov/imap/i-2732b/
Data_Quality_Information:
  Attribute_Accuracy:
    Attribute_Accuracy_Report: There are no attributes associated with a GeoTIFF image.
  Completeness_Report: The multibeam bathymetric data, on which this image is based, were corrected for tidal elevation during the survey using sea level measured at the NOAA Boston tide gage.  This assumes that the tidal elevation and phase are the same as Boston across the survey area.  Further processing to correct for the spatial and temporal changes in tidal elevation across the survey area would improve the sounding data and may be undertaken at a later time.
  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 western Massachusetts Bay map quadrangle 2, 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, Canada, 
        was used to process and grid the multibeam bathymetric soundings and produce shaded-relief images.  The metadata for the grids describes the processing steps applied to the navigation and bathymetric soundings.  The following processing steps produced the image of shaded-relief bathymetry: 

        1.  Create a 6-m grid of the bathymetric soundings for Massachusetts Bay using the SwathEd routine weighgrid.  

        Command line:  weigh_grid -fresh_start -omg -tide -coeffs -mindep -2 -maxdep -800 -beam_mask -beam_weight -custom_weight EM1000_Weights -butter -power 2 -cutoff 12 -lambda 3 gridFile filename.merged

        2.  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

        3.  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

        4.  Convert the contrast-stretched shaded relief image from SwathEd format to a tiff file using the netpbm utilities (http://netpbm.sourceforge.net/):

        Command line:  rawtopgm -headerskip 1024 image_width image_height filename_shade.stretch | pnmtotiff -none - > filename.tif

        5.  Create an ESRI world file (tfw) for the shaded relief tiff 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 filename_shade.stretch
      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.  Correct world file.
      Process_Date: 200702
      Source_Produced_Citation_Abbreviation: q2_srelief.tif
      Source_Produced_Citation_Abbreviation: q2_srelief.tfw
      Process_Contact:
        Contact_Information:
          Contact_Person_Primary:
            Contact_Person: William Danforth
            Contact_Organization: U.S. Geological Survey
Spatial_Data_Organization_Information:
  Direct_Spatial_Reference_Method: Raster
  Raster_Object_Information:
    Raster_Object_Type: Pixel
    Row_Count: 2237
    Column_Count: 3934
    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: 6.000000
          Ordinate_Resolution: 6.000000
        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:
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: 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/q2_srelief.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: 20070403
  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
