1. Mineral Resources
2. Online Spatial Data

Alaska map quadrangles at 1:250,000 scale

Frequently anticipated questions:

• What does this data set describe?
  1. How might 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?

What does this data set describe?

1. How might this data set be cited?
   U.S. Geological Survey, 2010, Alaska map quadrangles at 1:250,000 scale.

   Online Links:

   • https://mrdata.usgs.gov/ak/quadrangles/

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -178.0
   East_Bounding_Coordinate: 178.0
   North_Bounding_Coordinate: 72.0
   South_Bounding_Coordinate: 51.25
   

3. What does it look like?
4. Does the data set describe conditions during a particular time period?

   Calendar_Date: 2010

   Currentness_Reference:

   Date these data were accessioned for use on mrdata.usgs.gov.

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 Vector data set. It contains the following vector data types (SDTS terminology):
      • G-polygon (154)
   2. What coordinate system is used to represent geographic features?
      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.0001. Longitudes are given to the nearest 0.0001. Latitude and longitude values are specified in decimal degrees. The horizontal datum used is World Geodetic System 1984.
      The ellipsoid used is WGS 84.
      The semi-major axis of the ellipsoid used is 6378137.
      The flattening of the ellipsoid used is 1/298.257.
      
7. How does the data set describe geographic features?

   ak250

   Shapefile attributes (Source: Alaska DNR)

   AREA

   Area in square degrees (Source: this dataset)

   Range of values
   Minimum:	1
   Maximum:	4
   Units:	square degrees NAD83

   PERIMETER

   Perimeter in degrees (Source: this dataset)

   Range of values
   Minimum:	6
   Maximum:	10
   Units:	degrees NAD83

   AK250GEO_

   Arbitrary identifier (Source: this dataset)

   Range of values
   Minimum:	2
   Maximum:	152
   Units:	NAD83

   AK250GEO_I

   Arbitrary identifier (Source: this dataset)

   Range of values
   Minimum:	1
   Maximum:	153
   Units:	NAD83

   NAME

   Name of the map quadrangle (Source: this dataset) Upper case ASCII text.

   SHORTNAME

   Three-letter abbreviation (Source: this dataset) Upper case ASCII text.

   QCODE

   Two-letter abbreviation (Source: this dataset) Upper case ASCII text.

   QUADNO

   Quadno in square degrees (Source: this dataset)

   Range of values
   Minimum:	1
   Maximum:	153
   Units:	square degrees NAD83

   UTM

   UTM zone (Source: this dataset)

   Range of values
   Minimum:	1
   Maximum:	60
   Units:	NAD83

   DRGNAME

   Code value used for the quadrangle in USGS digital raster graphic products. (Source: this dataset) Lower case ASCII text.

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • U.S. Geological Survey
2. Who also contributed to the data set?
3. To whom should users address questions about the data?
   Schweitzer, Peter, N

   Geology, Energy, and Minerals Science Center

   12201 Sunrise Valley Drive Mail Stop 954

   Reston, VA
   

   USA

   703-648-6533 (voice)

   [email protected]

Why was the data set created?

Provide general geographic reference for users of specific GIS applications, including those able to interpret KML.

How was the data set created?

1. From what previous works were the data drawn?

   ADNR (source 1 of 1)

   Alaska Department of Natural Resources - Information Resource Management Section, 1993, USGS 1:250,000 Alaska Quadrangle Boundaries.

   Type_of_Source_Media: Vector digital data
   Source_Scale_Denominator: 250000
   Source_Contribution:

   Quadrangle boundaries obtained from this source; derivative KML contains additional links to geographic catalog on https://mrdata.usgs.gov/general/

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

   Date: 30-Dec-2020 (process 1 of 1)

   Metadata improved to remove errors and warnings. Contact information updated. Person who carried out this activity:
   

   Peter N Schweitzer

   USGS Geology, Energy, and Minerals Science Center

   Geologist

   Mail Stop 954

   12201 Sunrise Valley Dr

   Reston, VA
   

   USA

   703-648-6533 (voice)

   703-648-6252 (FAX)

   [email protected]

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?
   Quadrangles appear to cover the entire state of Alaska, but this information has not been verified using a more recent authoritative source.
5. How consistent are the relationships among the observations, including topology?
   This information has not been rigorously checked against a more recent authoritative source.

How can someone get a copy of the data set?

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)
   
   Schweitzer, Peter, N

   Geology, Energy, and Minerals Science Center

   12201 Sunrise Valley Drive Mail Stop 954

   Reston, VA
   

   USA

   703-648-6533 (voice)

   [email protected]
2. What's the catalog number I need to order this data set? ak250
3. What legal disclaimers am I supposed to read?

   This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards (or with the North American Stratigraphic Code). Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

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

     Data format:	Quadrangle boundaries with names and codes in format Shapefile (version 1.0)
     Network links:	https://mrdata.usgs.gov/ak/quadrangles/ak250.zip

     Data format:	Quadrangle boundaries with names and codes in format WMS (version 1.3.0)
     Network links:	https://mrdata.usgs.gov/services/ak250?request=GetCapabilities&service=WMS&version=1.3.0

   • Cost to order the data: none

Who wrote the metadata?

Dates:

Last modified: 29-Dec-2020

Metadata author:

Schweitzer, Peter, N

Geology, Energy, and Minerals Science Center

12201 Sunrise Valley Drive Mail Stop 954

Reston, VA

USA

703-648-6533 (voice)

[email protected]

Metadata standard:

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