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
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,
Data set describes the geology of Paleozoic through Quaternary units in
the Alligator Ridge area, which hosts disseminated gold deposits. These digital files were used to create the 1:24,000-scale geologic map of the Buck Mountain East and Mooney Basin Summit Quadrangles and parts of the Sunshine Well NE and Long Valley Slough Quadrangles, White Pine County, east-central Nevada.
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.
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.
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.
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.
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
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
Date: 1999 (process 2 of 3)
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.
Date: 17-Nov-2000 (process 3 of 3)
Creation of original metadata record
Person who carried out this activity:
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.