Walsh, Gregory J. , 2016, Bedrock geologic map of the Hartland and North Hartland quadrangles, Windsor County, Vermont, and Sullivan and Grafton Counties, New Hampshire: Scientific Investigations Map 3361, U.S. Geological Survey, Reston, Virginia.
This is a Vector data set. It contains the following vector data types (SDTS terminology):
Planar coordinates are encoded using coordinate pair
Abscissae (x-coordinates) are specified to the nearest 0.000100
Ordinates (y-coordinates) are specified to the nearest 0.000100
Planar coordinates are specified in feet
The horizontal datum used is North American Datum of 1983.
The ellipsoid used is Geodetic Reference System 80.
The semi-major axis of the ellipsoid used is 6378137.000000.
The flattening of the ellipsoid used is 1/298.257222.
This map supersedes Walsh (1998) and part of Lyons (1955). Walsh, G.J., 1998, Digital bedrock geologic map of the Vermont part of the Hartland quadrangle, Windsor County, Vermont: U.S. Geological Survey Open-File Report 98-123, 17 p., scale 1:24,000. Lyons, J.B., 1955, Geology of the Hanover quadrangle, New Hampshire-Vermont: Geological Society of America Bulletin, v. 66, no. 1, scale 1:62,500.
The bedrock geology was mapped to study the tectonic history of the area and to provide a framework for hydrogeologic characterization of the fractured bedrock of Vermont and New Hampshire. The digital data are intended for use by all government, academic, commercial, or other agencies in need of digital geologic map information. The report contains a GIS database, two large-format color sheets in Adobe Portable Document Format (PDF), metadata, and a readme.txt file.
Person who carried out this activity:
All attributes digitized during the creation process were verified by displaying the lines and points in the database with respect to the USGS 7.5-minute topographic base map (1:24,000 scale), but no formal tests were performed.
The data were created on a USGS 7.5-minute topographic map at 1:24,000 scale. Therefore, the horizontal accuracy is assumed to be within National Map Accuracy Standards, with a horizontal accuracy of 45.6 feet at the 95% confidence level. Locational information in the field was provided by a Garmin eTrex Venture GPS receiver.
The data were delineated on a USGS 7.5-minute topographic map at 1:24,000 scale. Therefore, the vertical accuracy is assumed to be within National Map Accuracy Standards, with a vertical accuracy of 11.9 feet at the 95% confidence level.
The geologic contacts were delineated on a USGS 7.5-minute topographic map based on observations at the outcrops shown in the database. Not all outcrops within the area were identified or visited during mapping. The geologic contacts might change if additional outcrops are discovered or exposed as the natural land changes or as the result of development. The features in the database are not based on legal parcels or definitions.
These data are believed to be logically consistent, though no tests were performed. Geometry is topologically clean.
Are there legal restrictions on access or use of the data?
- Although all data released in this report have been used by the U.S. Geological Survey (USGS), no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and related materials and (or) the functioning of the software. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
- Use_Constraints: none
USGS Scientific Investigations Map 3361
These data were prepared by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, product or process disclosed in this report, and represents its use would not infringe privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of this data and related materials. Reference therein to any specific commercial product, process, or related service by trade name, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.
|Data format:||Geologic units and related features in format ArcGIS Geodatabase (version 10)|
|Data format:||Geologic units and related features in format Google Earth (version 5.2)|
|Data format:||Bedrock geologic map in 2 sheets in format Adobe Acrobat (version 1.5)|