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Geologic map of the Alligator Ridge area, including the Buck Mountain East and Mooney Basin Summit Quadrangles and parts of the Sunshine Well NE and Long Valley Slough Quadrangles, White Pine County, Nevada

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?

What does this data set describe?

1. How should this data set be cited?

   Nutt, Constance J. , 2000, Geologic map of the Alligator Ridge area, including the Buck Mountain East and Mooney Basin Summit Quadrangles and parts of the Sunshine Well NE and Long Valley Slough Quadrangles, White Pine County, Nevada: U.S. Geological Survey Geologic Investigations Series Map I-2691, U.S. Geological Survey, Denver, Colorado.

   Online Links:

   • <http://greenwood.cr.usgs.gov/pub/i-maps/i-2691/>

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -115.625

   East_Bounding_Coordinate: -115.41

   North_Bounding_Coordinate: 39.875

   South_Bounding_Coordinate: 39.626

3. What does it look like?

   <http://greenwood.cr.usgs.gov/pub/i-maps/i-2691/i-2691so.pdf> (PDF)

   graphic representation of the map layout

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

   Calendar_Date: 2000

   Currentness_Reference: publication date

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

   Geospatial_Data_Presentation_Form: map

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.

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

      The map projection used is Transverse Mercator.

      Projection parameters:

      Scale_Factor_at_Central_Meridian: 1

      Longitude_of_Central_Meridian: -115.5

      Latitude_of_Projection_Origin: 0.0

      False_Easting: 0

      False_Northing: 0

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 1
      Ordinates (y-coordinates) are specified to the nearest 1
      Planar coordinates are specified in Meters

      The horizontal datum used is North American Datum of 1927.
      The ellipsoid used is Clarke 1866.
      The semi-major axis of the ellipsoid used is 6378206.4.
      The flattening of the ellipsoid used is 1/294.98.
      

7. How does the data set describe geographic features?

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Constance J. Nutt

2. Who also contributed to the data set?

   Constance J. Nutt mapped the geology from 1993 to 1997. Map was digitized by and ARC/INFO database created by Tracey Mercier, Clark Woodward, and Nancy Shock. Database structure checked by Nancy Shock. Norma J. Maes prepared the Adobe Illustrator map layout, which was used for the printed paper map and gif and pdf plot and browse graphic files. F.C. Brunstein edited the geologic map and the Illustrator layout and prepared the metadata.

3. To whom should users address questions about the data?
   Constance J. Nutt
   U.S. Geological Survey
   geologist
   MS 905, USGS, Denver Federal Center
   Denver, CO 80225
   USA
   

   (303) 236-1562 (voice)
   cnutt@usgs.gov
   

Why was the data set created?

Digital representation of geologic mapping facilitates the presentation and analysis of earth-science data. Digital maps may be displayed at any scale or projection, however the geologic data in this coverage is not intended for use at a scale larger that 1:24,000.

How was the data set created?

1. From what previous works were the data drawn?

   Nutt (1997) (source 1 of 2)

   Nutt, Constance J. , 1997, unpublished mapping of the Alligator Ridge area, White Pine County, Nevada.

   Type_of_Source_Media: hand drawn inked greenline mylar

   Source_Scale_Denominator: 24000

   Source_Contribution: New and compiled geologic mapping

   Topographic base maps (source 2 of 2)

   U.S. Geological Survey, 1982 and 1990, Buck Mountain East (provisional edition), Mooney Basin Summit (provisional edition), Long Valley Slough, and Sunshine Well NW 7.5 minute topographic quadrangles, Nevada.

   Type_of_Source_Media: conventional negatives

   Source_Scale_Denominator: 24000

   Source_Contribution: base map for geologic map

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

   Date: 1999 (process 1 of 2)

   The original inked geology was digitized in ARC/INFO. The lines and polygon attributes were checked against the original geology and corrected as neccessary. Shadeset and lineset attributes were added in ARC. The digital database was quality checked against original materials, and the database structure was checked. The ARC/INFO files were imported into Illustrator 8, and the map layout was completed in Illustrator. The Illustrator layout was used to produce the GIF and PDF browse graphic files and the plot file, as well as the printed paper map. The illustrator layout was proofed before the GIF and PDF files were made and before the map was printed.

   Date: 1999 (process 2 of 2)

   Conventional negatives and clear-film positives for all four quadrangles were obtained from USGS National Mapping Division. Clear-film positives of the four quadrangles were trimmed and mosaicked conventionally; then contact negative and clear-film positives of the mosaicked base were produced by NMD photolab. The clear-film mosaic was scanned as an 8-bit index color TIFF (.tif) file. The file was opened in Adobe Photoshop: 8-bit indexed color was changed to 8-bit grayscale; Unsharp mask was applied to clean up and sharpen the image; specks, scratches, and other imperfections were cleaned up; file was then changed from 8-bit grayscale to 1-bit and resaved as a .tif file. File was georeferenced in ARC/INFO and then imported into Illustrator layout using MaPublisher filter to align georeferenced base. Several very small dropouts occurred when scanning the base map; author and editor agreed that the dropouts were not critical to the quality of the base map.

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 observations, including topology?

   Visual proof of computer plot against orginal inked geology on greenline mylar.

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:

This database is not meant to be used or displayed at any scale other than 1:24,000.

1. Who distributes the data set? (Distributor 1 of 2)
   U.S. Geological Survey, Central Publishing Group
   Database Administrator
   MS 902, USGS, Denver Federal Center
   Denver, CO 80225
   USA
   

   (303) 236-7684 (voice)
   nshock@usgs.gov
   

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

   USGS Geologic Investigations Series I-2691

3. What legal disclaimers am I supposed to read?

   Although these data have been used by the USGS and have been successfully imported into data base programs, no warranty, expressed or implied, is made by the USGS as to how successfully or accurately the data can be imported into any specific application software running on any specific hardware platform. The fact of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in connection therewith. This data base GIS is not meant to be used or displayed at any scale other than 1:24,000.

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

     Data format:	Geologic units and structural features in format ARC/INFO export (version 7.1.2) Size: 3.8 megabytes
     Network links:	<http://greenwood.cr.usgs.gov/pub/i-maps/i-2691/arc/>

   • Cost to order the data: none

---

1. Who distributes the data set? (Distributor 2 of 2)
   U.S. Geological Survey
   USGS Information Services
   Denver, CO 80225
   USA
   

   1 (888) ASK-USGS (voice)
   

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

   I-2691

3. What legal disclaimers am I supposed to read?

   none

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

     Available as a paper map product consisting of one printed map sheet.

   • Cost to order the data:

     For current prices of USGS information products, please see <http://mapping.usgs.gov/esic/prices/>.

Who wrote the metadata?

Dates:

Last modified: 17-Nov-2000

Metadata author:

Frederick C Brunstein
U.S. Geological Survey, CR
Mail Stop 902
P.O. Box 25046
Denver, CO 80225
USA

303-236-5477 (voice)
303-236-6287 (FAX)
cbrunste@usgs.gov

Metadata standard:

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