## NAME

           mgd77togmt  - Convert an MGD-77 ascii file to a binary gmt
           file

## SYNOPSIS

           mgd77togmt [ -Llist ] [ mgd77file ] -Flegid -Ystart_year [
           -Ainformation ] [ -Itime_increment ] [ -V ]

## DESCRIPTION

           mgd77togmt  reads an ASCII MGD-77 format file [or standard
           input] and creates  a  binary  gmt  file.  The  16  header
           records  specified  in the MGD-77 documentation may or may
           not be present. If two-way  travel  times  are  available,
           mgd77togmt  will  convert  those to corrected depths using
           the Carter tables. Both old and new (Y2K-compiant)  MGD-77
           files are supported.

           -L     Name  of  file  with  several records of the format
                  mgd77file legid start_year. For multiple files, use
                  this  option rather than the -F -Y combination.  -F
                  Leg id that will be used in file name  (legid.gmt).

           -Y     The year of the first data point in the file

## OPTIONS

           No  space between the option flag and the associated argu
           ments.

           -A     Set an optional 10 character information string  to
                  be stored in the header [Default is blank].

           -I     Used for files where time is missing. The increment
                  is used to calculate fake times.

           -V     Selects verbose  mode,  which  will  send  progress
                  reports to stderr [Default runs "silently"].

## EXAMPLES

           To create a gmt file from the ASCII file c2104.mgd77, try

           mgd77togmt c2104.mgd77 -Y1977 -Fc2104

           To  create new gmt files from all the mgd77-file listed in
           list.d, try

           mgd77togmt -Llist.d -V

## SEE ALSO

           dat2gmt, gmt

## REFERENCES

           Wessel, P., and W. H. F. Smith, 2001, The Generic  Mapping
           Tools  (GMT)  version  3.4 Technical Reference & Cookbook,
           SOEST/NOAA.
           Wessel, P., and W. H. F. Smith, 1998, New,  Improved  Ver
           sion  of  Generic Mapping Tools Released, EOS Trans., AGU,
           79 (47), p. 579.
           Wessel, P., and W. H. F. Smith, 1995, New Version  of  the
           Generic  Mapping Tools Released, EOS Trans., AGU, 76 (33),
           p. 329.
           Wessel, P., and W. H. F. Smith, 1995, New Version  of  the
           Generic Mapping Tools Released, http: American Geophysical
           Union.
           Wessel, P., and W. H. F. Smith, 1991, Free Software  Helps
           Map and Display Data, EOS Trans., AGU, 72 (41), p. 441.

           MGD77  Task  Group,  1977,  The  Marine  Geophysical  Data
           Exchange Format - 'MGD77', Key to Geophysical Records doc
           umentation  No. 10, National Geophysical and Solar-Terres
           trial Data Center, Boulder, CO.

           Carter, D. J. T., Echo Sounding  Correction  Tables:  For
           merly  Matthews' Tables,' 150 pp, Hydrographic Department,
           Ministry of Defense, Taunton, Somerset, England, 1980.

                               15 Oct 2001              MDG77TOGMT(l)