USGS Digital Raster Graphics (drg) - Various vintage

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?
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• Who wrote the metadata?

Title: USGS Digital Raster Graphics (drg) - Various vintage

Abstract:

USGS digital raster graphics (drg) are color image versions of the USGS topographical series maps. The vintage of the original input data varies considerably and has not been updated even if the USGS has updated the base data.

Two series

1. USGS 1:24,000 (7.5 minute) Topographic Maps of various recent vintage

There is no survey publication information available on the 1:24,000 series

2. USGS 1:125,000 (30 minute) historic Topographic Maps (vintage range 1890 to 1920).

Details on vintage of 1:125,000 historic series, based on information printed in borders of unmerged quadrangles:

The image mosaic is made up of 6 quads

Top row from left to right

Snohomish Surveyed 1983-95, published 1895

Sultan Surveyed 1919-21, published 1921

Skykomish Surveyed 1897 & 1902, published 1902

Bottom row left to right

Tacoma Surveyed 1894-95, published 1900

Cedar Lake Surveyed 1910-11, published 1913

Snoqualmie Pass Surveyed 1900-01, published 1901

Supplemental_Information:

Historic 1890-1920 version obtained by King County Dept of Natural Resources and Parks, Water and Lands Resource Division through University of Washington Library website during May, 2004. Originally obtained as six separate quadrangles. Stripping of borders, rectification and mosaicing performed May, 2004 by WLRD.

1. How should this data set be cited?

   United States Geological Survey (USGS) and University of WA Library, Various, USGS Digital Raster Graphics (drg) - Various vintage: King County, King County, WA.

   Online Links:

   • None

   Other_Citation_Details:

   King County is responsible for the mosaiced and formatted raster images. The USGS is credited with the original interpretations and scanning.

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -121.500000

   East_Bounding_Coordinate: -121.100000

   North_Bounding_Coordinate: +47.800000

   South_Bounding_Coordinate: +47.100000

   Description_of_Geographic_Extent:

3. What does it look like?

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

   Beginning_Date:

   Ending_Date: 1970

   Currentness_Reference: Publication date

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

   Geospatial_Data_Presentation_Form: Raster Image

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

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

7. How does the data set describe geographic features?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • United States Geological Survey (USGS) and University of WA Library

2. Who also contributed to the data set?

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

   Mike Leathers
   KC GIS Center
   GIS Data Coordinator
   201 S Jackson St
   Seattle, WA 98104
   USA
   

   206-263-4867 (voice)
   

General use for orientation to natural and manmade features and general elevation. Must be used with disgression due to changes in the real world that are not updated in the images.

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?

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

Access_Constraints: None

Use_Constraints:

Users should be aware that the image mosaic is a compliation of multiple tiles that have seams different than the tiling scheme used by King County. The vintage of these tiles may vary considerably, thus information may change without crossing an image seam.

Egdematching errors (along original quad boundaries) are especially significant for historic version. This is probably the result of changing survey methods and changing geographic referencing standards over the 30 year span the topographic surveying was performed. Error is not consistent even within individual quads.

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

   Mike Leathers
   KCGIS Center
   GIS Data Coordinator
   201 S Jackson St
   Seattle, WA 98104
   USA
   

   206-263-4867 (voice)
   

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

   Not applicable

3. What legal disclaimers am I supposed to read?

   King County disclaims any warranty of use of any digital product or data beyond that for which it was designed.

4. How can I download or order the data?

Dates:

Last modified: 14-May-2004

Metadata author:

Mike Leathers
KCGIS Center
GIS Data Coordinator
201 S Jackson St
Seattle, WA 98104
USA

206-263-4867 (voice)
mike.leathers@metrokc.gov

Metadata standard:

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