Identification_Information:

  Citation:
    Citation_Information:
      Originator: A.J. Stevenson
      Originator: Florence L. Wong
      Publication_Date: 2002
      Title: Bathymetric xyz data for Glacier Bay at 5-meter intervals.
      Edition: Version 1.0, December 10, 2002
      Geospatial_Data_Presentation_Form: map
      Series_Information:
        Series_Name: USGS Open-File Report
        Issue_Identification: 02-391
      Publication_Information:
        Publication_Place: Menlo Park, California
        Publisher: U.S. Geological Survey
      Online_Linkage: <URL:http://geopubs.wr.usgs.gov/open-file/02-391>

  Description:

    Abstract:

      This data set consists of 5-m gridded bathymetric data for Glacier
      Bay, Alaska, in xyz form.
      The data were interpolated across "nodata" gaps that
      were no more than 30 meters wide.

      Data were collected during May 29 - June 6, 2001, by
      contract with Thales Geosolutions
      (http://www.thales-geopacific.com/) aboard the
      R/V Davidson as part of a cooperative survey conducted by the
      U.S. National Park Service and the U.S. Geological
      Survey (Biological Resources and Coastal and Marine
      Geology).  The instrument was a Reson 8111 multibeam
      echosounder (http://reson.com/sb8111.htm). The raw
      data were reduced by Thales.


    Purpose:

      These data are intended for science researchers, students, policy
      makers, and the general public.  The data can be
      used with geographic information systems (GIS) software
      to display geologic and oceanographic information.

    Supplemental_Information:

      Additional information about the field activities from
      which this data set was derived are available online at
      http://walrus.wr.usgs.gov/infobank/d/d101gb/html/d-1-01-gb.meta.html

      Any use of trade, product, or firm names is for descriptive purposes
      only and does not imply endorsement by the
      U.S. Government.

      Specifications for the Reson SeaBat 8111 Multibeam Echosounder
      (http://www.reson.com/sb8111.htm)

      > Operating frequency:  100 kHz
      > Number of beams:  101
      > Beamwidth across track:  1.5 degrees
      > Beamwidth along track:  1.5 degrees
      > Center-to-center beam separation:  1.5 degrees
      > Pulse length:  Variable, operator selectable
      > Depth range:  3 - 1000 meters
      > Transducer depth rating:  100 meters
      > Max. update rate:  35 swaths per second
      > Max. vessel Speed:  20 knots
      > Stabilization:  Pitch stabilization within +/- 10 degrees
      > Projector beam control:  External pitch sensor
      > Hydrophone size (Dia./arc/length):  640mm, 220 degrees, 200mm
      > Processor Dimensions (HWD):  177 x 483 x 434 mm
      > Tranceiver Dimensions (HWD):  267 x 450 x 427 mm
      > Weight: (with 15m cable):
      >   Hydrophone Dry: 42 kg Wet: 36 kg
      >   Projector Dry: 30 kg Wet: 23 kg
      > Transceiver weight:  13.6 kg
      > Processor weight:  20 kg

      Although this Federal Geographic Data Committee-compliant metadata
      file is intended to document the data set in nonproprietary form,
      as well as in ArcInfo format, this metadata file may include some
      ArcInfo-specific terminology.

  Time_Period_of_Content:
    Time_Period_Information:
      Single_Date/Time:
        Calendar_Date: 2002
    Currentness_Reference: Ground Condition

  Status:
    Progress: In work
    Maintenance_and_Update_Frequency: As Needed.

  Spatial_Domain:
    Bounding_Coordinates:
      West_Bounding_Coordinate: -136.40276708
      East_Bounding_Coordinate: -135.91167668
      North_Bounding_Coordinate: 58.75728909
      South_Bounding_Coordinate: 58.35942274

  Keywords:
    Theme:
      Theme_Keyword_Thesaurus: None
      Theme_Keyword: bathymetry
      Theme_Keyword: multibeam
      Theme_Keyword: echosounder
    Place:
      Place_Keyword_Thesaurus: None
      Place_Keyword: Glacier Bay
      Place_Keyword: Alaska

  Access_Constraints: None.

  Use_Constraints: Data not to be used for navigational purposes.

  Point_of_Contact:
    Contact_Information:
      Contact_Person_Primary:
        Contact_Person: Florence L. Wong
        Contact_Organization:
          United States Geological Survey (USGS)
          Coastal and Marine Geology (CMG)
      Contact_Position: Geologist, GIS Coordinator
      Contact_Address:
        Address_Type: mailing and physical address
        Address: USGS, MailStop 999, 345 Middlefield Road
        City: Menlo Park
        State_or_Province: CA
        Postal_Code: 94025-3561
        Country: USA
      Contact_Voice_Telephone: (650) 329-5327
      Contact_Facsimile_Telephone: (650) 329-5190
      Contact_Electronic_Mail_Address: fwong@usgs.gov

  Native_Data_Set_Environment:
    SunOS, 5.7, sun4u UNIX
    ArcInfo version 8.0.2

  Browse_Graphic:
    Browse_Graphic_File_Name: glacier.gif
    Browse_Graphic_File_Description:
      index map of Glacier Bay
      multibeam bathymetry data
    Browse_Graphic_File_Type: GIF

Data_Quality_Information:
  Attribute_Accuracy:
    Attribute_Accuracy_Report: Not applicable.

  Logical_Consistency_Report: Not applicable for raster data.

  Completeness_Report:
    Data values are missing in and around shallow or emergent
    features (islands) and where adjoining trackline coverage was
    not overlapping.

  Positional_Accuracy:
    Horizontal_Positional_Accuracy:
      Horizontal_Positional_Accuracy_Report:
        Navigation was multiple DGPS [differential global
        positioning systems] coupled up with 2 very precise DR
        [dead-reckoning] 3-axis accelerometers, all integrated in
        WinFrog (proprietary software from Thales Geosolutions
        http://www.thales-geopacific.com/offshore/index.html).
        The best functional test we did was crossties, which
        suggested that average navigational errors were on the
        order of 1 meter, with (rare) maximum errors being about 3
        meters.  (A.J. Stevenson, written communtication, October
        2001)

  Lineage:

    Process_Step:
      Process_Description:
        Raw data processed by contractor Thales Geosolutions and
        provided as 10-m and 5-m xyz values in UTM 8 coordinate
        system.
      Process_Date: 2001

    Process_Step:
      Process_Description:
        F.L. Wong converted xyz to ArcInfo grids.  Data were
        processed in 50,000-point blocks.  Each block of points
        was used to GENERATE a point coverage.

        The point coverage for each block was merged with
        adjoining blocks, the grid IDW function was applied
        with default options, and the resulting grid clipped
        to the boundary of the block.  All the interpolated
        grids were merged into a continuous grid GLACIER05MIG
        that was corrected by a mask that omitted data in
        holes that exceed 30 meters in width.

        The masking grid was constructed as follows: a unit grid
        (data cells = 1, all others = nodata) was copied from
        a 5-m uninterpolated grid.  The unit grid was converted to a polygon
        coverage from which polygons with areas of less than
        1000 square meters were removed in bulk.  The remaining
        interior polygons were inspected in Arcedit and removed
        if the width were about 30 meters or less.  This polygon
        coverage was converted back to a grid to be applied as
        a mask to the merged grids described in the previous
        paragraph.

      Process_Date: 2001

    Process_Step:
      Process_Description:
        UTM grid was converted to a point coverage by Arc tool GRIDPOINT.
        Point coverage was projected to decimal degrees, and longitude,
        latitude, and depth values extracted.

      Process_Date: 2002

    Process_Step:
      Process_Description:
        First draft of metadata created by curator using
        FGDCMETA.AML ver. 1.35 08/02/2000 on ArcInfo data set
        /arcdata/bathymetry/glacier05mg
      Process_Date: 20011018

Spatial_Data_Organization_Information:
  Direct_Spatial_Reference_Method: Point
  Point_and_Vector_Object_Information:
    SDTS_Terms_Description:
      SDTS_Point_and_Vector_Object_Type: Point
      Point_and_Vector_Object_Count: 16906963

Spatial_Reference_Information:
  Horizontal_Coordinate_System_Definition:
    Geographic:
      Latitude_Resolution: 0.00004910904
      Longitude_Resolution: 0.00004910904
      Geographic_Coordinate_Units: Decimal Degrees
    Geodetic_Model:
      Horizontal_Datum_Name: nad83
      Ellipsoid_Name: GRS1980
      Semi-major_Axis: 6378206.4
      Denominator_of_Flattening_Ratio: 294.98

Entity_and_Attribute_Information:
  Overview_Description:
    Entity_and_Attribute_Overview:
      Each record consists of three fields: longitude, latitude, and
      depth in meters.  Example of records:

      > -136.26066,58.75442,-137.124
      > -136.26074,58.75438,-139.409
      > -136.26066,58.75438,-137.124
      > -136.26057,58.75438,-136.976

    Entity_and_Attribute_Detail_Citation: none

Distribution_Information:
  Distributor:
    Contact_Information:
      Contact_Organization_Primary:
        Contact_Organization:
          United States Geological Survey (USGS)
          Coastal and Marine Geology (CMG)
        Contact_Person: Florence L. Wong
      Contact_Position: Geologist, GIS Coordinator
      Contact_Address:
        Address_Type: mailing and physical address
        Address: USGS, MailStop 999, 345 Middlefield Road
        City: Menlo Park
        State_or_Province: CA
        Postal_Code: 94025-3561
        Country: USA
      Contact_Voice_Telephone: (650) 329-5327
      Contact_Facsimile_Telephone: (650) 329-5190
      Contact_Electronic_Mail_Address: fwong@usgs.gov

  Distribution_Liability:
    Please recognize the U.S. Geological Survey (USGS) as the source of
    this information.

    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.

    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 this data, software, or related materials.

Metadata_Reference_Information:
  Metadata_Date: 20021210
  Metadata_Review_Date: 2002
  Metadata_Contact:
    Contact_Information:
      Contact_Organization_Primary:
        Contact_Organization:
          United States Geological Survey (USGS)
          Coastal and Marine Geology (CMG)
        Contact_Person: Florence L. Wong
      Contact_Position: Geologist, GIS Coordinator
      Contact_Address:
        Address_Type: mailing and physical address
        Address: USGS, MailStop 999, 345 Middlefield Road
        City: Menlo Park
        State_or_Province: CA
        Postal_Code: 94025-3561
        Country: USA
      Contact_Voice_Telephone: (650) 329-5327
      Contact_Facsimile_Telephone: (650) 329-5190
      Contact_Electronic_Mail_Address: fwong@usgs.gov
  Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata ("CSDGM version 2")
  Metadata_Standard_Version: FGDC-STD-001-1998
  Metadata_Access_Constraints: none
  Metadata_Use_Constraints: none