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Metadata for dem300m

Alaska 300m digital elevation model


Table of Contents

Identification Information
Data Quality Information
Spatial Data Organization Information
Spatial Reference Information
Distribution Information
Metadata Reference Information

Identification_Information:

  Citation
    Citation_Information
      Originator:        U.S. Geological Survey EROS Alaska Field Office
      Publication_Date:  19970512
      Title:             Alaska 300m digital elevation model
      Geospatial_Data_Presentation_Form:  map
      Publication_Information
        Publication_Place:  Anchorage, Alaska
        Publisher:          U.S. Geological Survey EROS Alaska Field Office
Online_Linkage: <URL:https://agdcftp1.wr.usgs.gov/pub/projects/dem/300m/akdem300m.tar.gz> Description Abstract: Digital elevation model 300m grid for Alaska, from Defense Mapping Agency 3-arc second 1x1 degree 1:250,000 scale Digitial Elevation Models. Source data for Digital Shaded-Relief Image of Alaska, USGS Map I-2585 Purpose: Display and analysis of terrain. Time_Period_of_Content Time_Period_Information Range_of_Dates/Times Beginning_Date: 19500101 Ending_Date: 0 Currentness_Reference: Publication Date Status Progress: Complete Maintenance_and_Update_Frequency: Unknown Spatial_Domain Bounding_Coordinates West_Bounding_Coordinate: -180.0 East_Bounding_Coordinate: -116.0 North_Bounding_Coordinate: 72.0 South_Bounding_Coordinate: 51.5 Keywords Theme Theme_Keyword_Thesaurus: None Theme_Keyword: DEM Theme_Keyword: DTM Theme_Keyword: elevation Theme_Keyword: relief Theme_Keyword: landforms Place Place_Keyword_Thesaurus: None Place_Keyword: Alaska Access_Constraints: None Use_Constraints: Point_of_Contact Contact_Information Contact_Organization_Primary Contact_Organization: U.S. Geological Survey EROS Alaska Field Office Contact_Person: Contact_Position: Contact_Address Address_Type: mailing and physical address Address: 4230 University Drive City: Anchorage State_or_Province: Alaska Postal_Code: 99508-4664 Country: USA Contact_Voice_Telephone: (907) 786-7020 Contact_Facsimile_Telephone: (907) 786-7036 Contact_Electronic_Mail_Address: agdcweb@usgs.gov Hours_of_Service: Monday-Friday, 8-5, Alaska Standard Time Native_Data_Set_Environment: Arc/Info version 7.0.3, Pathname =

Data_Quality_Information:

  Attribute_Accuracy
    Attribute_Accuracy_Report:
        See Vertical Accuracy. 
  Logical_Consistency_Report:
        None 
  Completeness_Report:
        None 
  Positional_Accuracy
    Horizontal_Positional_Accuracy
      Horizontal_Positional_Accuracy_Report:
        90 percent probability of 300m accuracy. 
    Vertical_Positional_Accuracy
      Vertical_Positional_Accuracy_Report:
        90 percent probability of 300m accuracy.
        See also: http://nsdi.usgs.gov/nsdi/wais/maps/dem1deg.HTML.
        and http://edcwww.cr.usgs.gov/glis/hyper/guide/1_dgr_dem. 
  Lineage
    Source_Information
      Source_Citation
        Citation_Information
          Originator:  Defense Mapping Agency
          Publication_Date:  19750101
          Title:  1-degree Digital Elevation Models
          Geospatial_Data_Presentation_Form:  map
          Publication_Information
            Publication_Place:  Reston, VA
            Publisher:  U.S. Geologic Survey
      Source_Scale_Denominator:  250000
      Type_of_Source_Media:  Unknown
      Source_Time_Period_of_Content
        Time_Period_Information
          Single_Date/Time
            Calendar_Date:  19500101
        Source_Currentness_Reference:  Publication Date
      Source_Citation_Abbreviation:  dma
      Source_Contribution:
          The data set was derived from this source.
    Process_Step
      Process_Description:
	The first step in producing the image was the creation of a statewide
	digital elevation model (DEM) using data produced in 1degree x 1degree blocks
	by the Defense Mapping Agency Topographic Center. These same data are currently 
	available from the Earth Science Information Center. 
	The original DEMs have a resolution of 3x6 arc-seconds in the horizontal 
	(approximately 90x90 m); vertical values were interpolated to the nearest meter 
	from digitized 200-ft contour. The 1-degree x 1-degree blocks were spliced together 
	in 1:250,000-scale quadrangles, most of which are 1-degree x 3-degree. Visible flaws 
	in the spliced data set were repaired using techniques such as data inversion, 
	replacement of missing data lines, and correction of geometric distortions. The 
	individual quadrangle data sets (153 quadrangles) were then sampled at a spacing of 
	30x30 arc-seconds (a ground resolution of approximately 900x450 m). Several 
	remaining omissions in the data were filled using hyposography from the Digital 
	Chart of the World (Defense Mapping Agency, 1992) together with surrounding DEM data. 
	This patched data set was reprojected and interpolated using a bilinear resampling 
	method to form a statewide data set in Albers Equal-Area Conic projection having a 
	grid-cell size of 300m. The final step in generating the based DEM was to delimit 
	the elevation data at sea level by adding a coastline digitized from 1:250,000-scale 
	USGS quadrangles. This 300-m data set achieves a degree of resolution suitable for 
	the creation of a sharp high-resoluytion shaded-relief image at 1:2,500,000 scale. 
	Data processing were preformed by Mike Fleming, USGS EROS Alaska Field Office. 

      Process_Date:  

Spatial_Data_Organization_Information:

  Direct_Spatial_Reference_Method:  Raster
  Raster_Object_Information
    Raster_Object_Type:  Point
    Row_Count:     8372
    Column_Count:  11503

Spatial_Reference_Information:

  Horizontal_Coordinate_System_Definition
    Planar
      Map_Projection
        Map_Projection_Name:  Albers Conical Equal Area
        Albers_Conical_Equal_Area
          Standard_Parallel:  55.0
          Standard_Parallel:  65.0
          Longitude_of_Central_Meridian:  -154.0
          Latitude_of_Projection_Origin:  50.0
          False_Easting:   0.00000
          False_Northing:  0.00000
      Planar_Coordinate_Information
        Planar_Coordinate_Encoding_Method:  row and column
        Coordinate_Representation
          Abscissa_Resolution:  64
          Ordinate_Resolution:  64
        Planar_Distance_Units:  meters
    Geodetic_Model
      Horizontal_Datum_Name:  North American Datum of 1927
      Ellipsoid_Name:   Clarke 1866
      Semi-major_Axis:  6378206.4
      Denominator_of_Flattening_Ratio:  294.98
  Vertical_Coordinate_System_Definition
    Altitude_System_Definition
      Altitude_Datum_Name:  NGVD29
      Altitude_Resolution:  1
      Altitude_Distance_Units:  METERS
      Altitude_Encoding_Method:  Implicit coordinate

Distribution_Information:

  Distributor
    Contact_Information
      Contact_Organization_Primary
        Contact_Organization:  U.S. Geological Survey EROS Alaska Field Office
        Contact_Person:        
      Contact_Position:        
      Contact_Address
        Address_Type:  mailing and physical address
        Address:            4230 University Drive
        City:               Anchorage
        State_or_Province:  Alaska
        Postal_Code:        99508-4664
        Country:            USA
      Contact_Voice_Telephone:          (907) 786-7020
      Contact_Facsimile_Telephone:      (907) 786-7036
      Contact_Electronic_Mail_Address:  agdcweb@usgs.gov
      Hours_of_Service:  Monday-Friday, 8-5, Alaska Standard Time
  Distribution_Liability:  Users must assume responsibility to determine the
                           usability of this data for their purposes.

Metadata_Reference_Information:

  Metadata_Date:  19970512
  Metadata_Review_Date:  19970512
  Metadata_Contact
    Contact_Information
      Contact_Organization_Primary
        Contact_Organization:  U.S. Geological Survey EROS Alaska Field Office
        Contact_Person:        
      Contact_Address
        Address_Type:  mailing and physical address
        Address:            4230 University Drive
        City:               Anchorage
        State_or_Province:  Alaska
        Postal_Code:        99508-4664
        Country:            USA
      Contact_Voice_Telephone:          (907) 786-7020
      Contact_Facsimile_Telephone:      (907) 786-7036
      Contact_Electronic_Mail_Address:  agdcweb@usgs.gov
      Hours_of_Service:  Monday-Friday, 8-5, Alaska Standard Time
  Metadata_Standard_Name:  FGDC Content Standards for Digital Geospatial Metadata
  Metadata_Standard_Version:  19940608


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Page Last Modified: Wednesday, 07-Dec-2016 12:17:09 AKST