Identification_Information:
  Citation:
    Citation_Information:
      Originator: USGS
      Publication_Date: 19970610
      Title: USGS Digital Raster Graphic 1:250,000 and 1:63,360 Quadrangles
      Geospatial_Data_Presentation_Form: map
      Publication_Information:
        Publication_Place: Reston, VA
        Publisher: USGS
  Description:
    Abstract:
      The Digital Raster Graphic (DRG) is a raster image of a
      scanned USGS topographic map. The collar information has
      been stripped off and the resulting image georeferenced
      to the Alaska Albers NAD83 grid

    Purpose:
      A DRG is useful as a source or background layer in a GIS,
      as a means to perform quality assurance on other digital products,
      and as a source for the collection and revision of DLG data.  DRG's
      can also be merged with other digital data, e.g. DEM's or DOQ's, to
      produce a hybrid digital file.
  Time_Period_of_Content:
    Time_Period_Information:
      Single_Date/Time:
        Calendar_Date: 20070101
    Currentness_Reference: "Ground Condition"
  Status:
    Progress: Complete
    Maintenance_and_Update_Frequency: "Irregular"
  Spatial_Domain:
    Bounding_Coordinates:
      West_Bounding_Coordinate: 157.55125214
      East_Bounding_Coordinate: 117.38252248

      North_Bounding_Coordinate: 67.56587136

      South_Bounding_Coordinate: 49.12879913

  Keywords:
    Theme:
      Theme_Keyword_Thesaurus: "None"
      Theme_Keyword: digital raster graphic
      Theme_Keyword: DRG
      Theme_Keyword: topographic map
    Place:
      Place_Keyword_Thesaurus:
        Department of Commerce, 1977, Countries,
        Dependencies, Areas of Special Sovereignty, and their Principal
        Administrative Divisions (Federal Information Processing Standard
        10-3): Washington, Department of Commerce, National Institute of
        Standards and Technology.
      Place_Keyword: US
    Place:
      Place_Keyword_Thesaurus:
        Department of Commerce, 1987, Codes for
        the Identification of the States, The District of Columbia and the
        Outlying Areas Of The United States, and Associated Areas (Federal
        Information Processing Standard 5-2): Washington, Department of
        Commerce, National Institute of Standards and Technology.
      Place_Keyword: NM
  Access_Constraints: "None"
  Use_Constraints:
    Acknowledgment of the USGS would be appreciated in
    products derived from these data.
  Data_Set_Credit:
    This DRG was produced through an Innovative
    Partnership agreement between The Land Information Technology
    Company, Ltd., of Aurora, CO and the USGS.
Data_Quality_Information:
  Attribute_Accuracy:
    Attribute_Accuracy_Report:
      The DRG is an 8-bit color image that employs
      a color palette to ensure uniform colors throughout a particular DRG
      series.  All DRG's within a series must have the same RGB value.
  Logical_Consistency_Report: Not Applicable
  Completeness_Report:
    The DRG is a faithfully reproduced digital image of
    the original source map.  Some differences may be detected between the
    source graphic used and the DRG due to the RGB values assigned that
    particular color.  The intent is to recreate those colors as near as
    possible.  Data completeness for DRG files reflect content of the source
    graphic.  Features may have been eliminated or generalized on the source
    graphic due to scale and legibility constraints.  For information on
    collection and inclusion criteria, see U.S. Geological Survey, 1994,
    Standards for 1:24,000-Scale Digital Line Graphs and Quadrangle Maps:
    National Mapping Program Technical Instructions and U.S. Geological
    Survey, 1994, Standards for Digital Line Graphs:  National Mapping Program
    Technical Instructions.
  Positional_Accuracy:
    Horizontal_Positional_Accuracy:
      Horizontal_Positional_Accuracy_Report:
        While the datum of the
        published map is retained to be consistent with other USGS digital
        data, this image is cast on the UTM and may be INCONSISTENT with the
        credit note on the image collar.
    Vertical_Positional_Accuracy:
      Vertical_Positional_Accuracy_Report:
        Refer to the DRG collar for
        information about vertical positional accuracy.
  Lineage:
    Source_Information:
      Source_Citation:
        Citation_Information:
          Originator: USGS
          Publication_Date: 1985
          Title: Portair SW
          Geospatial_Data_Presentation_Form: map
          Publication_Information:
            Publication_Place: Reston, VA
            Publisher: USGS
      Source_Scale_Denominator: 24000
      Type_of_Source_Media: "paper"
      Source_Time_Period_of_Content:
        Time_Period_Information:
          Single_Date/Time:
            Calendar_Date: 1985
        Source_Currentness_Reference: "ground condition"
      Source_Citation_Abbreviation: map1
      Source_Contribution: The source map is scanned to produce the DRG.
    Process_Step:
      Process_Description:
        The production procedures, instrumentation,
        hardware, and software used in the collection of standard DRG
        products vary depending on systems used at the contract, cooperator
        or USGS production sites.  The majority of DRG data sets are
        acquired through government contract.  The process step describes,
        in general, the process used in the production of standard DRG data
        sets.

        1. Production of a DRG begins with the scanning of a paper
        7.5-minute topographic map (map1) on a high-resolution scanner.
        Scanning resolutions range from 500 - 1000 dpi with the output file
        running between 160-300 mb.

        2. Removal of screens (descreening) and color quantization to reduce
        the number of colors also takes place during the scanning phase.

        3. The raw scan file is then transformed and georeferenced using UTM
        coordinates of the sixteen 2.5-minute grid ticks, which are obtained
        using the in-house produced program COORDAT and stored in a ground
        control file.  Those sixteen 2.5-minute ticks are interactively
        visited and assigned their respective UTM coordinates. USGS program
        XSHAPES4 then performs a piecewise linear rubber sheet
        transformation.

        to resample the file to 250 dpi.

        5.  The image file is converted to a TIFF and further reduced by
        converting the file to a run length encoding Packbits
        compression(type 32773).

        6.  The color palette of the compressed DRG is then standardized by
        replacing the original RGB values assigned during the scanning
        process with standard RGB value combinations using the in-house
        produced TIFFREMAP program.

        7.  Prior to archiving the DRG undergoes the following quality
        assurance procedures:

        a. The color index values of each DRG are checked to ensure
        the RGB combinations are consistent with the standardized
        color palette.

        b. All DRG files are inspected to ensure that they are
        geometrically consistent with normal map presentation.

        c. Selected DRG's are checked to ensure that data elements in
        the DRG metadata file correspond to the map collar information
        and to the information in the associated image file.

        d. Selected DRG's are checked for georeferencing accuracy by
        comparing the book value of latitude and longitude tick marks
        with corresponding tick intersections in the DRG image.

        e. Transformations are checked on selected DRG's by comparing
        the positions of well defined points, such as UTM grid
        intersections in the graphic product, with the corresponding
        image points in the DRG.

        USGS DRG production specifications are available on request from
        the National Mapping Division and Mid-Continent Mapping Center by
        contacting:

        Rolla-ESIC
        U.S. Geological Survey
        1400 Independence Rd., MS231
        Rolla, MO 65401-2602
        Phone (573)308-3500
        Facsimile (573)308-3615
        E-mail to mcmcesic@usgs.gov
        World Wide Web: http://mcmcweb.er.usgs.gov/drg/
      Source_Used_Citation_Abbreviation: map1
      Process_Date: 19970610
Spatial_Data_Organization_Information:
  Direct_Spatial_Reference_Method: Raster
  Raster_Object_Information:
    Raster_Object_Type: Pixel
    Row_Count: 6769
    Column_Count: 5445
Spatial_Reference_Information:
  Horizontal_Coordinate_System_Definition:
    Planar:
      Map_Projection:
        Map_Projection_Name: Albers Conical Equal Area
        Albers_Conical_Equal_Area:
          Standard_Parallel: 55.000000
          Standard_Parallel: 65.000000
          Longitude_of_Central_Meridian: -154.000000
          Latitude_of_Projection_Origin: 50.000000
          False_Easting: 0.000000
          False_Northing: 0.000000
      Planar_Coordinate_Information:
        Planar_Coordinate_Encoding_Method: coordinate pair
        Coordinate_Representation:
          Abscissa_Resolution: 0.000100
          Ordinate_Resolution: 0.000100
        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
Entity_and_Attribute_Information:
  Overview_Description:
    Entity_and_Attribute_Overview:
      Each raster entity or pixel contains a color index from 0 through 12
      referencing a color palette of RGB values from 0 through 255 in
      which the standard colors used in the DRG are defined.

      USGS DRG Color Palette

      Digital Number    Color       Red      Green    Blue

      0           Black       0        0        0
      1           White       255      255      255
      2           Blue        0        151      164
      3           Red         203      0        23
      4           Brown       131      66       37
      5           Green       201      234      157
      6           Purple      137      51       128
      7           Yellow      255      234      0
      8        Light Blue     167      226      226
      9        Light Red      255      184      184
      10       Light Purple   218      179      214
      11       Light Grey     209      209      209
      12       Light Brown    207      164      142
    Entity_and_Attribute_Detail_Citation:
      Draft Standards for Digital
      Raster Graphic.
Distribution_Information:
  Distributor:
    Contact_Information:
      Contact_Organization_Primary:
        Contact_Organization:
          Earth Science Information Center,  U.S.
          Geological Survey Contact Address
      Contact_Address:
        Address_Type: mailing address
        Address: 507 National Center
        City: Reston
        State_or_Province: Virginia
        Postal_Code: 22092
      Contact_Voice_Telephone: 1 800 USA MAPS
      Contact_Voice_Telephone: 1 703 648 6045
  Distribution_Liability:
    Although these data have been processed
    successfully on a computer system at the USGS, no warranty expressed
    or implied is made by the USGS regarding the use of the data on any
    other system, nor does the act of distribution constitute any such
    warranty. The USGS will warrant the delivery of this product in
    computer-readable format and will offer appropriate adjustment of
    credit when the product is determined unreadable by correctly
    adjusted computer input peripherals, or when the physical medium is
    delivered in damaged condition.  Requests for adjustment of credit
    must be made within 90 days from the date of this shipment from the
    ordering site.
  Standard_Order_Process:
    Digital_Form:
      Digital_Transfer_Information:
        Format_Name: TIFF
        Format_Version_Number: 6.0
        File_Decompression_Technique: Packbits
      Digital_Transfer_Option:
        Offline_Option:
          Offline_Media: "CD-ROM"
          Recording_Format:
            "ISO 9660";  DRG image files with
            corresponding metadata files.
    Fees: For delivery on CD-ROM, the charge is $32 per CD-ROM
Metadata_Reference_Information:
  Metadata_Date: 19970610
  Metadata_Contact:
    Contact_Information:
      Contact_Organization_Primary:
        Contact_Organization: U.S. Geological Survey
      Contact_Address:
        Address_Type: mailing address
        Address: 590 National Center
        City: Reston
        State_or_Province: Virginia
        Postal_Code: 22092
      Contact_Voice_Telephone: 1 703 648 4533
      Contact_Electronic_Mail_Address:
        Copies of this publication are
        available from anonymous File Transfer Protocol (anonymous FTP);
        ftp://fgdc.er.usgs.gov/
  Metadata_Standard_Name:
    "Content Standards for Digital Geospatial
    Metadata"
  Metadata_Standard_Version: FGDC-STD-001-1998