The ASCII file MtWashington-ft.grd contains a United States Geological Survey (USGS) 7.5-minute Digital Elevation Model (DEM) for the Mt. Washington quandrangle. This data set covers an area of roughly 14,000-by-10,000 meters in the White Mountains of New Hampshire, USA, with elevations posted every 30 meters. The data are referenced to Universal Transverse Mercator (UTM), Zone 19, in the North American Datum of 1927. Horizonal units are meters and vertical units are feet. "No data" elements near the edge of the data grid have a value of -32766. Data Translation ---------------- This file was derived by translating an Spatial Data Transfer Standard (STDS) Raster Profile data set to Arc ASCII Grid format. The following is from the self-documentation of the original SDTS data set: Filename: '2463CATD.DDF' Title: 'MOUNT WASHINGTON, NH - 24000' ProfileID: 'SDTS RASTER PROFILE' ProfileVersion: 'DRAFT VERSION JULY 1997' MapDate: '1997' DataCreationDate: '19971202' HorizontalDatum: 'North American 1927' MapRefSystem: 'UTM' ZoneNumber: 19 XResolution: 30 YResolution: 30 NumberOfRows: 472 NumberOfCols: 345 HorizontalUnits: 'METERS' VerticalUnits: 'FEET' MinElevation: 1205 MaxElevation: 6280 Data Header ----------- The ASCII file (MtWashington-ft.grd) contains the following header. Items 3-5 are in meters. Items 3 and 4 give the UTM easting and northing of the lower left corner of the data grid. ncols 345 nrows 472 xllcorner 310380.000000 yllcorner 4901880.000000 cellsize 30 nodata_value -32766 Translation Date ----------------- May 3, 2000 General Information on USGS DEM Products ---------------------------------------- http://edc.usgs.gov/products/elevation/dem.html README File from the Original SDTS Data Set --------------------------------------------------------------------------- README File: SeriesID: 7.5 Minute DEM September 2, 1997 Welcome! This directory contains a Spatial Data Transfer Standard (SDTS), Raster Profile (RP) compliant transfer, produced by the National Mapping Division of the United States Geological Survey (USGS). PURPOSE OF TRANSFER: This transfer was created as part of the SDTS Mass Conversion of 1997, when large amounts of the USGS digital archive were converted to SDTS/RP. This transfer was produced from the 7.5 min Digital Elevation Model (i.e. DEM). STANDARD AUTHORITY: FIPS 173: The Spatial Data Transfer Standard Part 5: Raster Profile With BIIF Extension, Draft Version July 1997 ISO 8211 CONFORMANCE: All files with extension *.DDF are in the ISO 8211 file transfer format. All SDTS spatial addresses are expressed in two 32 bit binary sub-fields defined by the ISO8211. Files are Level 2 of ISO 8211. CATALOG DIRECTORY MODULE xxxxCATD.DDF: Each transfer will contain this catalog directory module which contains a listing of every SDTS ISO 8211 file included in the transfer. (xxxx indicates a four-character transfer base which is common to all files in a transfer.) IDENTIFICATION MODULE xxxxIDEN.DDF: This module contains information that describes the overall characteristics of the data in a transfer. REFERENCES: "The Spatial Data Transfer Standard Mapping of the USGS Digital Elevation Model" -- draft document which describes SDTS transfers of DEM data, including detailed information on each module. The file can be downloaded from the SDTS ftp site in two formats: Word Perfect - ftp://sdts.er.usgs.gov//pub/sdts/datasets/raster/dem/demmap.wp Postscript - ftp://sdts.er.usgs.gov//pub/sdts/datasets/raster/dem/demmap.ps POINT OF CONTACT: SDTS Task Force | Information on SDTS is also U.S. Geological Survey | available on FTP site 1400 Independence | sdts.er.usgs.gov (144.47.162.236) Rolla, MO 65401 | Web: http://mcmcweb.er.usgs.gov/sdts E-MAIL: sdts@usgs.gov