DIGITAL FILE DESCRIPTIONS The digital data, text of this report (figures in separate files) can be downloaded via 'anonymous ftp' from a USGS system named greenwood.cr.usgs.gov (136.177.21.122). The files are located in a directory named /pub/open-file-reports/ofr-97-0085 and are described below in Table 1. TABLE 1. FILE DESCRIPTIONS FILE NAME FILE TYPE DESCRIPTION ----data files----- profiles.lis ascii text Listing of principal facts in 80-column format with labeled columns profiles.pos UNIX binary, Station identifier, longitude (degrees), sequential post file latitude (degrees), and 6 channels of (see below for principal facts (see below) for all description of format) profile data. profiles.asc ascii post file (see Same as profiles.bin but in ascii below for description FORTRAN format (a8, 8g16.8). of file format) -----figures----- fig1.eps fig2.eps encapsulated Figures 1, 2, 3, and 4 in encapsulated fig3.eps postscript postscript, no preview fig4.eps fig1.tif fig2.tif tagged image file Figures 1, 2, 3, and 4 in ".tif" fig3.tif format bitmap format fig4.tif fig1.prn fig2.prn postscript print Figures 1, 2, 3, and 4 in a format fig3.prn files to print on 300 dpi postscript fig4.prn printers ----text-------- readme.txt ascii text This file: Text describing digital files. text.txt ascii text A file containing the text of open-file report 97-85, without figures or Appendix A. text.prn postscript print A print file of the text of file open-file report 97-85, without figures, for 300 dpi postscript printers. POST FILE FORMAT USGS post file format consists of an eight-character station identifier, followed by eight real numbers, called channels. The channels for the post files associated with this report are described below. CHANNEL DESCRIPTION 1 Longitude in decimal degrees (west longitudes are negative) 2 Latitude in decimal degrees 3 Station altitude in meters above sea level 4 Observed gravity in mGal with a constant value of 980,000 mGal removed 5 Inner-zone terrain correction (zones A-F), in mGal 6 Outer-zone terrain correction (zones G-X), in mGal 7 Free-air gravity anomaly, in mGal 8 Complete (terrain-corrected) Bouguer anomaly, reduced using a density of 2.67 g/cc, in mGal