THEME: Elevation: Shaded Relief Grid
1. Data set name: elev_shd
2. Originator: Interrain Pacific
3. Date: 2/17/96
4. Edition: n/a
5. Description: This layer is a composite, merged and generalized shaded relief image organized by 1:250,000 scale USGS quadrangles within the Glacier Bay ecosystem. Interrain Pacific derived this shaded relief layer from elevation data which is based on digital elevation model (DEM) data at 1:250,000 scale acquired from the USGS EROS Alaska Field Office. The shading is a mathematically calculated value to provide the illusion of a terrain surface being illuminated by an implied light source with azimuth of 270 and alttitude 35 degrees. It is useful as a back-drop for other data because it gives an intuitive view of the landscape.
6. Data Set Status:
___In preparation
Anticipated Completion Date_____
_X_Completed and operational
___On going; Update Frequency:____
Data Set Status Comments:
7. Geographic Coverage Description: This merged and generalized
shaded relief image layer covers the entire Glacier Bay ecosystem.
Please check appropriate USGS 1:250,000 maps:
_X_Atlin _X_Juneau _X_Mount Fairweather
_X_Port Alexander ___Skagway _X_Sumdum
_X_Yakutat
8. West Bounding Coordinate: 149 00 00 W
9. East Bounding Coordinate: 140 00 00 W
10. North Bounding Coordinate: 63 00 00 N
11. South Bounding Coordinate: 59 00 00 N
12. Theme keywords:
_X_elevation
_X_geomorphology/landforms
13. Access Restrictions: Data transfer costs will be based on staff time and media costs.
14. Use Restrictions: Data may not be sold.
15. Processing Information:
Software used to automate: ARC/INFO
Software Version: 7.0.3
Hardware Platform: SUN
Operating System used: UNIX
File Name: elev250.bil
File Size:
Feature Type:
___Point (data point) ___Line (Arc) ___Polygon _X_Grid ___Text ___Other
16. Raster File Form
___ADRG ARC Digitized Raster Graphic (ARC/INFO GRID format)
___ADRI ARC Digitized Raster Imagery
___BIL Imagery, band interleaved by line
___BIP Imagery, band interleaved by pixel
___BSQ Imagery, band sequential
___DEM USGS Digital Elevation Model
___ERD74 ERDAS image files version 7.4
___ERD81 ERDAS IMAGINE image files, ver8.1
___GRAS3 GRASS (Geographic Resources Analysis Support System)v3
___GRAS4 GRASS (Geographic Resources Analysis Support System) v4
___IDL Interactive Data Language image file
___MOSS Multiple Overlay Statistical System export file
___TIFF Tagged Image File Format
___Other Other Raster format not listed ________________________
17. Raster File Sensor:
___LANDSAT Thematic Mapper TM
___LANDSAT Multispectral scanner MSS
___NOAA AVHRR
___SPOT
___aircraft scanner_____________
___aircraft video_______________
___scanned airphotos____________
___scanned hard copy
___radar type____________________
___other not listed______________
18. Sensor Resolution______meters
19. Imagery Information
___panchromatic ___multispectral
Band width/channels used___________
20. Vector File Format:
___ARCE6 ARC/INFO Export format version 6
___ARCE7 ARC/INFO Export format 7
___ARCE ARC/INFO Export other version___
___ASCII ASCII file, formatted for text attributes, declared format
___DXF9 AUTOCAD Drawing Exchange Format, ver9
___DXF10 AUTOCAD Drawing Exchange Format,ver 10
___DXF11 AUTOCAD Drawing Exchange Format, ver 11
___DLGO US Geological Survey Digital Line GraphOptional Format
___DLGS US Geological Survey Digital Line GraphStandard Format
___ATLAS GIS ______
___Other ARC/INFO version 7.0.3
II. DATA QUALITY INFORMATION
1. Attribute Accuracy Explanation: Interrain Pacific has not conducted any formal accuracy assessments on this data layer or the source datasets.
2. Attribute Accuracy: __________%
__X__Unknown_____
_X_no accuracy assessment performed on dataset
3. Description of Data Completeness: This data is complete for all areas of the greater Glacier Bay ecosystem except those portions that fall within Canada.
4. Minimum Mapping Unit: ______ Unknown___ n/a___
5. Positional Accuracy Comments:
6. Source Information:
USGS EROS Alaska Field Office;
4230 University Drive, Anchorage, Alaska 99508;
786-7020 (Contact person: Mark Shasby)
"Digital Elevation Models: Data User's Guide." 1990. USGS National
Mapping Program Technical Instructions, Data Users Guide 5. Published by
USGS, Reston, VA.
7. Date of Source Data:
8. Scale of Source Data: Originally developed at a resolution of 90 m, these datasets have been resampled to 100 m.
9. Data Processing Description: The USGS EROS Alaska Field Office processed Standard Defense Mapping Agency (DMA) DEMs into LAS images. Interrain Pacific then converted these files to elevation data in an ARC/INFO GRID format and used ARC/INFO HILLSHADE command to develop the shaded relief images
.III. SPATIAL DATA ORGANIZATION INFORMATION
1. Data Structure:
___point (x,y)
___vector(line >1 x,y)
_X_raster (grid cell)
___tin (3 dimensional x,y,z)
___Other__________
Cell size = 100 meters
2. Raster File Row: 4514
3. Raster File Column: 5370
4. Raster File Vertical:
5. Raster File Number of Bytes per Pixel:
6. Raster file origin: X=126779.343, Y=6215002.257
IV. SPATIAL REFERENCE INFORMATION
1. Map Projection Name
Projection: UTM
Units: Meters
Zunits: Unknown
Zone: 8
Datum: NAD27
Shperoid: CLARK 1866
V. ENTITY AND ATTRIBUTE INFORMATION
1. Attribute Labels: Pixel values refer to level of illumination from
an implied lighting source in the northwest to create a shaded surface.
Values are 0 (darkest) to 255 (brightest).
2. Attribute Definition Source:
VI. DISTRIBUTION INFORMATION
1. Distributor: Interrain Pacific
2. Distribution Liability: Interrain Pacific makes no express or implied
warranties with respect to the character, fitness, function, accuracy,
or capabilities of the information presented or the appropriateness for
any users purposes. In no event will Interrain Pacific be liable for any
incidental, indirect, special, consequential or other damages suffered
by the user of this information or other person.
3. Standard Order Process: Data will be provided on tape or CD-ROM based
on written requests.
4. Hardware media type: 8mm tape, CD-ROM.
5. File Decompression Technique: None.
6. Decompressed Data Transfer Size:
VII. METADATA REFERENCE INFORMATION
1. Metadata Date: March 3, 1997
2. Metadata Contact: Interrain Pacific
VIII. CONTACT INFORMATION
1. Primary Contact Person: Interrain Pacific
2. Contact Mailing Address:
1200 NW Front Ave., Suite 470A
Portland, OR 97209
3. Contact Voice Telephone: (503) 226-8108
4. Contact Facsimile Telephone: (503) 226-8110
5. Contact Electronic Mail Address: pacificgis@igc.apc.org