7.5-minute Digital Elevation Model (10 meter resolution)

Frequently-anticipated questions:

• What does this data set describe?
  1. How should this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

Title: 7.5-minute Digital Elevation Model (10 meter resolution)

Abstract:

USGS Digital Elevation Model (DEM) data files are digital representations of cartographic information in a raster form. DEMs consist of a sampled array of elevations for a number of ground positions at regularly spaced intervals. These digital cartographic/geographic data files are produced by the U.S. Geological Survey (USGS) as part of the National Mapping Program.

1. How should this data set be cited?

   U.S. Geological Survey EROS Data Center, 1999, 7.5-minute Digital Elevation Model (10 meter resolution): U. S. Geological Survey, Sioux Falls, SD.

   Online Links:

   • <URL:http://www.sdvc.uwyo.edu/24k/dem10.html>
   • <URL:http://edcwww.cr.usgs.gov/glis/hyper/guide/usgs_dem>

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -111.36

   East_Bounding_Coordinate: -104

   North_Bounding_Coordinate: 45.0

   South_Bounding_Coordinate: 41.0

3. What does it look like?

4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 1999

   Ending_Date: 2001

   Currentness_Reference: publication date of source maps

5. What is the general form of this data set?

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?

      This is a raster data set.

   2. What coordinate system is used to represent geographic features?

      Grid_Coordinate_System_Name: Universal Transverse Mercator

      Universal_Transverse_Mercator:

      UTM_Zone_Number: 12

      Transverse_Mercator:

      Scale_Factor_at_Central_Meridian: .09996

      Longitude_of_Central_Meridian: -111

      Latitude_of_Projection_Origin: 0.0

      False_Easting: 0.0

      False_Northing: 0.0

      Planar coordinates are encoded using row and column
      Abscissae (x-coordinates) are specified to the nearest 10
      Ordinates (y-coordinates) are specified to the nearest 10
      Planar coordinates are specified in meters

7. How does the data set describe geographic features?

   Entity_and_Attribute_Overview:

   The digital elevation model is composed of a 6- character integer raster representing a gridded form of a topographic map hypsography overlay, with a value in meters. In Wyoming, elevations range from approximately 900-4200 meters.

   Entity_and_Attribute_Detail_Citation:

   U.S.Department of the Interior, U.S. Geological Survey, 1992, Standards for digital elevation models: Reston, VA,

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • U.S. Geological Survey EROS Data Center

2. Who also contributed to the data set?

3. To whom should users address questions about the data?

   Data Manager
   Spatial Data and Visualization Center
   Box 4008 University Station
   Laramie, Wyoming 82071
   USA
   

   307-766-2751 (voice)
   n/a
   

   Hours_of_Service: 8:00 - 5:00 MST

Geospatial elevation data are utilized by the scientific and resource management communities for global change research, hydrologic modeling, resource monitoring, mapping, and visualization applications.

1. From what previous works were the data drawn?

2. How were the data generated, processed, and modified?

   Date: 2003 (process 1 of 2)

   Digital Elevation Model (10 meter resolution) were downloaded from www.MapMart.com (originating at USGS EROS Date Center) in SDTS data format in UTM, referenced to NAD 27, Clarke 1866. These data were then converted to ESRI ArcGIS GRID format using the SDTS conversion tool within ESRI ArcGIS Toolbox. The grids were then reprojected from UTM, NAD27 to UTM, NAD83. Twelve quadrangles were downloaded: Meadowville, Laketown, Sage Creek, Garden City, Bear Lake South, Sheppen Creek, Saint Charles, Bear Lake North, Pegrem Creek, Paris, Dingle, and Pegrem. The ESRI ArcGIS MERGE command was used to merged all of the reprojected grids into one composite grid. The ESRI ArcGrid command, sample, was then used to export the composite grid as an x,y,z file.

   Person who carried out this activity:
   

   Jane F. Denny
   U.S. Geological Survey
   Geologist
   384 Woods Hole Road
   Woods Hole, MA 02543
   USA
   

   508-457-2311 (voice)
   508-457-2310 (FAX)
   jdenny@usgs.gov
   

   Date: 2003 (process 2 of 2)

   All values less than 1806 meters were removed from the xyz file using the UNIX 'awk' command. The xyz file was then imported into Interactive Visualization Systems (IVS) DMAGIC program. The data were regridded within DMAGIC at the default values (10 meter). The data were then saved as DMAGIC .geo and .dtm files. The DMAGIC Shade program was used to assign a color map to the .dtm file generating a .shade file. The .dtm, .geo, and .shade files were then combined to produce a .sd, or Fledermaus object file. The .sd file was then imported into Fledermaus to view the data in three dimensions. The 'Create Map Sheet' program within Fledermaus was then used to create a grayscale GEOTIFF of the 10 meter DEM. The GEOTIFF was then imported into ArcView. The resulting grid cell size of the GEOTIFF is ~ 15 meters.

   Person who carried out this activity:
   

   Jane F. Denny
   U.S. Geological Survey
   Geologist
   384 Woods Hole Road
   Woods Hole, MA 02543
   USA
   

   508-457-2311 (voice)
   508-457-2310 (FAX)
   jdenny@usgs.gov
   

3. What similar or related data should the user be aware of?

1. How well have the observations been checked?

   not yet available

2. How accurate are the geographic locations?

   Not available yet. Assumed to be the most accurate of all the USGS DEM products

3. How accurate are the heights or depths?

   not available yet

4. Where are the gaps in the data? What is missing?

   not yet available

5. How consistent are the relationships among the observations, including topology?

   not yet available

Are there legal restrictions on access or use of the data?

Access_Constraints: None

Use_Constraints: None.

1. Who distributes the data set? (Distributor 1 of 1)

   Data Manager
   Spatial Data and Visualization Center
   Box 4008 University Station
   Laramie, Wyoming 82071
   USA
   

   307-766-2751 (voice)
   n/a
   

2. What's the catalog number I need to order this data set?

3. What legal disclaimers am I supposed to read?

   The distributor shall not be held liable for improper or incorrect use of this data, based on the description of appropriate/inappropriate used described in this metadata document.

4. How can I download or order the data?
   • Availability in digital form:

     Data format:	ARCE (Arc/Info export) (version 7.0.4)
     Network links:	ftp.sdvc.uwyo.edu or <http://www.sdvc.uwyo.edu/clearinghouse>

   • Cost to order the data:

     No fees are required for downloading the data that is on-line. Some fees may be required to cover costs of tapes if data is required on tape media.

Dates:

Last modified: 31-Aug-2000

Metadata author:

Margo Berendsen
Box 4008 University Station
Laramie, Wyoming 82071
USA

307-766-2751 (voice)
meh@uwyo.edu

Metadata standard:

FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)