Provided by: gmt-common_5.4.3+dfsg-1_all bug


       pssegyz - Create imagemasked postscript from SEGY file


       pssegyz SEGYfile  -Jparameters
        -Ddeviation   -F[color] -W [  -Cclip ] [  -I ] [  -K ] [  -Lnsamp ] [  -Mntrace ] [  -N ]
       [  -O ] [  -P ] [  -Q<mode><value> ] [  -Sheader_x/header_y ] [  -U[stamp] ] [   -V[level]
       ] [  -Xx_offset ] [  -Yy_offset ] [  -Z ] [ -pflags ] [ -ttransp ]

       Note: No space is allowed between the option flag and the associated arguments.


       pssegyz  reads  a  native  (IEEE)  format SEGY file and produces a PostScript image of the
       seismic data. The imagemask operator is used so that the seismic data  are  plotted  as  a
       1-bit  deep  bitmap  in  a single (user-specified) color or gray shade, with a transparent
       background. The bitmap resolution is taken from the  current  GMT  defaults.  The  seismic
       traces  may  be plotted at their true locations using information in the trace headers (in
       which case order of the traces in the file is  not  significant).  Standard  GMT  geometry
       routines  are  used  so  that  in  principle any map projection may be used, however it is
       likely that the geographic projections will lead to  unexpected  results.  Beware  that  a
       couple of the options for pssegy are not available in pssegyz.

       Note   that   the   order   of   operations   before  the  seismic  data  are  plotted  is
       deviation*[clip]([bias]+[normalize](sample value)). Deviation determines how  far  in  the
       plot  coordinates  a  [normalized][biased][clipped] sample value of 1 plots from the trace

       The SEGY file should be a disk image of the tape format  (i.e.,  3200  byte  text  header,
       which  is  ignored,  400 byte binary reel header, and 240 byte header for each trace) with
       samples as native real*4 (IEEE real on all the platforms to which I have access).


              Seismic SEGY data set to be imaged.

       -Jparameters (more …)
              Select map projection.

              west, east, south, and north specify the region of interest, and  you  may  specify
              them  in decimal degrees or in [±]dd:mm[][W|E|S|N] format Append +r if lower
              left and upper right  map  coordinates  are  given  instead  of  w/e/s/n.  The  two
              shorthands  -Rg  and  -Rd stand for global domain (0/360 and -180/+180 in longitude
              respectively, with -90/+90 in latitude).  Alternatively  for  grid  creation,  give
              Rcodelon/lat/nx/ny,  where  code is a 2-character combination of L, C, R (for left,
              center, or right) and T, M, B for top, middle, or bottom. e.g., BL for lower  left.
              This  indicates  which  point on a rectangular region the lon/lat coordinate refers
              to, and the grid dimensions nx and ny with grid spacings via -I is used  to  create
              the corresponding region.  Alternatively, specify the name of an existing grid file
              and the -R settings (and grid spacing, if applicable) are  copied  from  the  grid.
              Appending  +uunit  expects projected (Cartesian) coordinates compatible with chosen
              -J and we inversely project to determine actual rectangular geographic region.  For
              perspective  view  (-p), optionally append /zmin/zmax.  In case of perspective view
              (-p), a z-range (zmin, zmax) can be appended to indicate the third dimension.  This
              needs to be done only when using the -Jz option, not when using only the -p option.
              In the latter case a perspective view of  the  plane  is  plotted,  with  no  third

              gives the deviation in X units of the plot for 1.0 on the scaled trace, This may be
              a single number (applied equally in X and Y directions) or the pair devX/devY.

              Fill trace (variable area, defaults to filling positive). Specify  the  color  with
              which the imagemask is filled.

       -W     Draw wiggle trace.

       You must specify at least one of -W and -F.


       -A     Flip   the   default  byte-swap  state  (default  assumes  data  have  a  bigendian

       -Cclip Sample value at which to clip data  (clipping  is  applied  to  both  positive  and
              negative values).

       -I     Fill negative rather than positive excursions.

       -K (more …)
              Do not finalize the PostScript plot.

              Override  number of samples per trace in reel header (program attempts to determine
              number of samples from each trace header if possible to allow for  variable  length

              Override  number  of  traces  specified in reel header. Program detects end of file
              (relatively) gracefully, but this  parameter  limits  number  of  traces  that  the
              program attempts to read.

       -N     Normalize trace by dividing by rms amplitude over full trace length.

       -O (more …)
              Append to existing PostScript plot.

       -P (more …)
              Select “Portrait” plot orientation.


              Can be used to change 5 different settings depending on mode:
                     -Qbbias to bias scaled traces (-Qb-0.1 subtracts 0.1 from values).

                     -Qidpi sets the dots-per-inch resolution of the image [300].

                     -Quredvel  to  apply  reduction  velocity  (-ve  removes  reduction  already

                     -Qxmult to multiply trace locations by mult.

                     -Qydy to override sample interval in reel header.

              Read trace locations from trace headers: headers is either c for CDP, o for offset,
              b  *num*  to read a long starting at byte num in the header (first byte corresponds
              to num=0), or a number to fix the location. First parameter for x,  second  for  y.
              Default has X and Y given by trace number.

       -U[[just]/dx/dy/][c|label] (more …)
              Draw GMT time stamp logo on plot.

       -V[level] (more …)
              Select verbosity level [c].


       -Y[a|c|f|r][y-shift[u]] (more …)
              Shift plot origin.

       -Z     Do not plot traces with zero rms amplitude.

       -p[x|y|z]azim[/elev[/zlevel]][+wlon0/lat0[/z0]][+vx0/y0] (more …)
              Select perspective view.

       -t[transp] (more …)
              Set PDF transparency level in percent.

       -^ or just -
              Print a short message about the syntax of the command, then exits (NOTE: on Windows
              just use -).

       -+ or just +
              Print  an  extensive  usage  (help)  message,  including  the  explanation  of  any
              module-specific option (but not the GMT common options), then exits.

       -? or no arguments
              Print  a  complete  usage (help) message, including the explanation of all options,
              then exits.


       To plot the SEGY file wa1.segy with normalized traces plotted at  true  offset  locations,
       clipped at +/-3 and with wiggle trace and positive variable area shading in black, use

              gmt pssegyz wa1.segy -JX5i/-5i -D1 -Jz0.05i -E180/5 -R0/100/0/10/0/10 \
                      -C3 -N -So -W -Fblack >


       Variable  area  involves filling four-sided figures of distressing generality. I know that
       some of the more complex degenerate cases are not dealt with  correctly  or  at  all;  the
       incidence  of such cases increases as viewing angles become more oblique, and particularly
       as the viewing elevation increases. Wiggle-trace plotting is not affected.


       gmt, pssegy, segy2grd


       2018, P. Wessel, W. H. F. Smith, R. Scharroo, J. Luis, and F. Wobbe