Identification_Information:
  Citation:
    Citation_Information:
      Originator: Page C. Valentine
      Originator: Tanya S. Unger
      Originator: Jessica L. Baker
      Publication_Date: 2005
      Title: sunillum.tif:  Sun-illuminated topographic imagery of the seafloor in the Stellwagen Bank National Marine Sanctuary region.
      Edition: 1.0
      Geospatial_Data_Presentation_Form: remote-sensing image
      Series_Information:
        Series_Name: Scientific Investigations Map
        Issue_Identification: 2840
      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/sim/2005/2840/data/sunillum/sunillum.zip
      Larger_Work_Citation:
        Citation_Information:
          Originator: Page C. Valentine
          Publication_Date: 2005
          Title: Sea floor image maps showing topography, sun-illuminated topography, backscatter intensity, ruggedness, slope, and the distribution of boulder ridges and bedrock outcrops in the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts
          Edition: 1.0
          Series_Information:
            Series_Name: Scientific Investigations Map
            Issue_Identification: 2840
          Publication_Information:
            Publication_Place: Woods Hole Science Center, Woods Hole, MA
            Publisher: U.S. Geological Survey, Coastal and Marine Geology Program
          Other_Citation_Details: scale 1:60,000, 6 maps, 12 sheets
          Online_Linkage: http://pubs.usgs.gov/sim/2005/2840/
  Description:
    Abstract: The sun-illuminated topographic imagery of the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts covers an area of approximately 1100 square nautical miles. The Stellwagen Bank NMS Mapping Project is designed to provide detailed maps of the Stellwagen Bank region's environments and habitats and the first complete multibeam topographic and sea floor characterization maps of a significant region of the shallow EEZ.  Data were collected on four cruises over a two year period from the fall of 1994 to the fall of 1996. The surveys were conducted aboard the Canadian Hydrographic Service vessel Frederick G. Creed, a SWATH (Small Waterplane Twin Hull) ship that surveys at speeds of up to 16 knots.
    Purpose: Development of interpretive seabed maps, sea floor imagery, and a GIS database that are accessible to scientists, policymakers, managers, and the general public.
  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: As needed
  Spatial_Domain:
    Bounding_Coordinates:
      West_Bounding_Coordinate: -70.6
      East_Bounding_Coordinate: -70.0333
      North_Bounding_Coordinate: 42.8
      South_Bounding_Coordinate: 42.0833
  Keywords:
    Theme:
      Theme_Keyword_Thesaurus: General
      Theme_Keyword: Geographic Information Systems
      Theme_Keyword: GIS
      Theme_Keyword: U.S. Geological Survey
      Theme_Keyword: USGS
      Theme_Keyword: Coastal and Marine Geology Program
      Theme_Keyword: CMGP
      Theme_Keyword: Woods Hole Science Center
      Theme_Keyword: WHSC
      Theme_Keyword: Frederick G. Creed
      Theme_Keyword: Swath Bathymetry
      Theme_Keyword: topographic data
      Theme_Keyword: sea floor topography
      Theme_Keyword: bathymetry
      Theme_Keyword: sun-illuminated imagery
      Theme_Keyword: gray scale image
      Theme_Keyword: GeoTIFF image
    Theme:
      Theme_Keyword_Thesaurus: ISO 19115 Topic Category
      Theme_Keyword: oceans and estuaries
      Theme_Keyword: imageryBaseMapsEarthCover
      Theme_Keyword: elevation
    Place:
      Place_Keyword_Thesaurus: General
      Place_Keyword: Massachusetts
      Place_Keyword: MA
      Place_Keyword: Stellwagen Bank National Marine Sanctuary
      Place_Keyword: SBNMS
      Place_Keyword: Shallow EEZ
      Place_Keyword: EEZ
      Place_Keyword: Gulf of Maine
      Place_Keyword: Atlantic Ocean
      Place_Keyword: Boston
  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.
    
    Not to be used for navigational purposes.
  Point_of_Contact:
    Contact_Information:
      Contact_Person_Primary:
        Contact_Person: Page C. Valentine
        Contact_Organization: U.S. Geological Survey
      Contact_Position: Research Geologist
      Contact_Address:
        Address_Type: mailing and physical address
        Address: U.S. Geological Survey
        Address: 384 Woods Hole Rd.
        City: Woods Hole
        State_or_Province: MA
        Postal_Code: 02543-1598
        Country: USA
      Contact_Voice_Telephone: (508) 548-8700 x2239
      Contact_Facsimile_Telephone: (508) 457-2310
      Contact_Electronic_Mail_Address: pvalentine@usgs.gov
  Browse_Graphic:
    Browse_Graphic_File_Name: http://pubs.usgs.gov/sim/2005/2840/data/sunillum/sunillum-thumb.gif
    Browse_Graphic_File_Description: Thumbnail image showing overview of the sun-illuminated topographic imager of the seafloor in the Stellwagen Bank National Marine Sanctuary region.
    Browse_Graphic_File_Type: GIF
  Browse_Graphic:
    Browse_Graphic_File_Name: http://pubs.usgs.gov/sim/2005/2840/data/sunillum/sunillum-browse.gif
    Browse_Graphic_File_Description: Image showing overview of the sun-illuminated topographic imager of the seafloor in the Stellwagen Bank National Marine Sanctuary region.
    Browse_Graphic_File_Type: GIF
  Native_Data_Set_Environment: Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.0.0.535
  Cross_Reference:
    Citation_Information:
      Originator: Page C. Valentine
      Originator: Tammie J. Middleton
      Originator: Sarah J. Fuller
      Publication_Date: 2001
      Title: Sea floor maps showing topography, sun-illuminated topography, and backscatter intensity of the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts
      Edition: 1.01
      Series_Information:
        Series_Name: Open-File Report
        Issue_Identification: 00-410
      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/of/of00-410/
  Cross_Reference:
    Citation_Information:
      Originator: Page C. Valentine
      Originator: Tanya S. Unger
      Originator: Jessica L. Baker
      Publication_Date: 2003
      Title: Sun-illuminated sea floor topography of the Stellwagen Bank National Marine Sanctuary off Boston, Massachusetts
      Edition: 1.0
      Geospatial_Data_Presentation_Form: map
      Series_Information:
        Series_Name: Geologic Investigations Map
        Issue_Identification: I-2676-B
      Publication_Information:
        Publication_Place: Woods Hole Science Center, Woods Hole, MA
        Publisher: U.S. Geological Survey, Coastal and Marine Geology Program
Data_Quality_Information:
  Attribute_Accuracy:
    Attribute_Accuracy_Report: The ship's position was determined with an accuracy of 10 m or better using a Magnavox 4200 geographic positioning system (GPS) receiver in conjunction with differential GPS corrections transmitted by U.S. Coast Guard radio beacons. At the start of each day, casts were made to record the sound velocity profile of the water column in the area to be surveyed. Sound velocity information was updated during the day whenever the survey moved from one area to another. Tidal corrections based on NOAA's Boston tide gauge were used to reference depth data to mean lower low water.  Sounding rates depend on water depth but vary from 2 to 4 per second in water depths less than 100 meters. Horizontal spatial resolution at these sounding rates is on the order of 10% of the water depth at 16 knots; however, vertical resolution is approximately 1% or better in the same depth range.
  Completeness_Report: The bathymetric data are displayed in real time on the Sun workstation using software designed and written by the Ocean Mapping Group, University of New Brunswick. This display allows data gaps to be identified during the survey and also gives a measure of the data quality.
  Positional_Accuracy:
    Horizontal_Positional_Accuracy:
      Horizontal_Positional_Accuracy_Report: Sounding rates depend on water depth but vary from 2 to 4 per second in water depths less than 100 meters. Horizontal spatial resolution at these sounding rates is on the order of 10% of the water depth at 16 knots; however, vertical resolution is approximately 1% or better in the same depth range.
    Vertical_Positional_Accuracy:
      Vertical_Positional_Accuracy_Report: Sounding rates depend on water depth but vary from 2 to 4 per second in water depths less than 100 meters. Horizontal spatial resolution at these sounding rates is on the order of 10% of the water depth at 16 knots; however, vertical resolution is approximately 1% or better in the same depth range.
  Lineage:
    Process_Step:
      Process_Description:
        The navigation and topographic data were both edited using SwathEd, a suite of multibeam software editing and display tools developed by Dr. John Hughes Clarke of the Ocean Mapping Group, University of New Brunswick (UNB).. Tidal corrections were obtained from NOAA's Boston Tide Gauge (Station 8443970) and merged into the data set using UNB's tidal routines. The topographic information was converted into an ASCII text file containing lat, long, and depth fields, using a script created by Bill Danforth at the U.S. Geological Survey. The ASCII file was brought into Arc/Info, and a grid was generated and processed using ESRI's Arc/Info version 7.0.4 software. A point coverage containing depth values was created using the routine point-generate.

        The grid was created based on the depth values for each of the points using the command pointgrid. The grid was filtered with a 9 by 9 focalmedian filter. Contours were generated using latticecontour. All editing and edgematching was done by hand using arcedit. The shaded relief images shown here were created using a light source that is 45 degrees above the horizon from an azimuth of 350 degrees. The vertical exaggeration in the images is four times. In effect, topographic relief is enhanced by illuminating the sea floor from a position 10 degrees west of north so that shadows are cast on the southern flanks of seabed features. Some features in the images are artifacts of data collection. They are especially noticeable where the seabed is smooth and include small highs and lows and unnatural-looking features and patterns that are oriented parallel or perpendicular to survey tracklines.
Spatial_Data_Organization_Information:
  Direct_Spatial_Reference_Method: Raster
  Raster_Object_Information:
    Raster_Object_Type: Pixel
    Row_Count: 8060
    Column_Count: 4718
    Vertical_Count: 1
Spatial_Reference_Information:
  Horizontal_Coordinate_System_Definition:
    Planar:
      Map_Projection:
        Map_Projection_Name: Mercator
        Mercator:
          Standard_Parallel: 41.65
          Longitude_of_Central_Meridian: -70.3167
          False_Easting: 0
          False_Northing: 0
      Planar_Coordinate_Information:
        Planar_Coordinate_Encoding_Method: row and column
        Coordinate_Representation:
          Abscissa_Resolution: 10.000000
          Ordinate_Resolution: 10.000000
        Planar_Distance_Units: meters
    Geodetic_Model:
      Horizontal_Datum_Name: North American Datum of 1983
      Ellipsoid_Name: Geodetic Reference System 80
Entity_and_Attribute_Information:
  Overview_Description:
    Entity_and_Attribute_Overview: Sun-illuminated topographic imagery combines contoured topography and sun-illuminated topographic imagery. The image shown here uses a sun elevation angle of 45 degrees above the horizon from an azimuth of 350 degrees and a vertical exaggeration of four times. In effect, topographic relief is enhanced by having the sun illuminate the sea floor from a position 10 degrees west of north so that shadows are cast on the southern flanks of seabed features. Unnatural-looking stripes and patterns oriented parallel or perpendicular to survey track lines are artifacts of data collection. Blank areas represent places where no data exists. The topographic imagery is identical to that shown on Sheet 3 of this report.
Distribution_Information:
  Distributor:
    Contact_Information:
      Contact_Person_Primary:
        Contact_Person: Page C. Valentine
        Contact_Organization: U.S. Geological Survey
      Contact_Position: Research Geologist
      Contact_Address:
        Address_Type: mailing and physical address
        Address: U.S. Geological Survey
        Address: 384 Woods Hole Rd.
        City: Woods Hole
        State_or_Province: MA
        Postal_Code: 02543-1598
        Country: USA
      Contact_Voice_Telephone: (508) 548-8700 x2239
      Contact_Facsimile_Telephone: (508) 457-2310
      Contact_Electronic_Mail_Address: pvalentine@usgs.gov
  Resource_Description: Downloadable Data
  Distribution_Liability:
    Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data.
    
    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
        Transfer_Size: 0.000
      Digital_Transfer_Option:
        Online_Option:
          Computer_Contact_Information:
            Network_Address:
              Network_Resource_Name: http://pubs.usgs.gov/sim/2005/2840/data/sunillum/sunillum.zip
        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: 20050823
  Metadata_Review_Date: 20050822
  Metadata_Contact:
    Contact_Information:
      Contact_Organization_Primary:
        Contact_Organization: U.S. Geological Survey
        Contact_Person: Page C. Valentine
      Contact_Position: Research Geologist
      Contact_Address:
        Address_Type: mailing and physical address
        Address: U.S. Geological Survey
        Address: 384 Woods Hole Rd.
        City: Woods Hole
        State_or_Province: MA
        Postal_Code: 02543
        Country: USA
      Contact_Voice_Telephone: (508) 548-8700 x2239
      Contact_Facsimile_Telephone: (508) 457-2310
      Contact_Electronic_Mail_Address: pvalentine@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
