Return to SIOSEIS examples.          Go to the list of seismic processes.          Go to SIOSEIS introduction.

September 2003 test of the SIO Geometrics

    Make sure the Sun executables are in a "nice" place.  sioseis, lsd, 
sio2hp, and xloadimage are used in this example.  You may have to set
shell parameter DISPLAY.  e.g.  setenv DISPLAY your_machine:0.0
Don't forget xhost +.

    The Geometrics tape output is SEG-D, not SEG-Y.  SEG-D is not for
the faint of heart;  dd'ing a SEG-D tape is not a good idea since
every shot is a file.
    Convert the SEG-D tape to a SEG-Y disk file.  The Geometrics records
24 channels, but the first use will have a four channel streamer.  
Only save traces 1-4 when converting to SEG-Y.

e.g.
sioseis << eof
procs segdin diskoa prout end
segdin
   ftr 1 ltr 4
   device /dev/rmt/0bn end
end
diskoa
   opath file1.segy end
end
prout
   fno 0 lno 999999 noinc 100 ftr 1 ltr 1 end
end
end
eof


     Following the AVON04 example:
>lsd file1.segy 1 10
      SHOT   TR       RP    TR ID  RANGE DELAY NSAMPS    SI   YR DAY HR MIN SEC
         1     1       0     0  1      0     0   7000  1000 2003 253 16  31  34
         1     2       0     0  1      0     0   7000  1000 2003 253 16  31  34
         1     3       0     0  1      0     0   7000  1000 2003 253 16  31  34
         1     4       0     0  1      0     0   7000  1000 2003 253 16  31  34
         2     1       0     0  1      0     0   7000  1000 2003 253 16  31  44
         2     2       0     0  1      0     0   7000  1000 2003 253 16  31  44
         2     3       0     0  1      0     0   7000  1000 2003 253 16  31  44
         2     4       0     0  1      0     0   7000  1000 2003 253 16  31  44
         3     1       0     0  1      0     0   7000  1000 2003 253 16  31  54
         3     2       0     0  1      0     0   7000  1000 2003 253 16  31  54


Do a QC check to make sure all 4 traces look good.  e.g.
sioseis << eof
procs diskin plot end
diskin
   ipath file1.segy ntodo 96 end
end
plot
   def .02 vscale 1.25 srpath sunfil.ras nsecs 7
   nibs 2859 recsp yes ann sh&tr taginc 1
   end
end
end
eof
xloadimage -r 90 sunfil.ras

(test data plot.)


   All four traces look okay, so "vertically stack" them by using
ntrgat 4 in diskin and adding stack in the procs.  Remember that
filter should be done after stack for speed.  Finding the right plot
"def" was hard because of the noise at the beginning of the data.
Avon04 plot
sioseis << eof
procs diskin stack filter plot end
diskin
   ntrgat 4
   ipath file1.segy ntodo 2000 end
end
filter
   ftype 0 pass 20 150 dbdrop 48 end
end
agc
   winlen .5 end
end
plot
   vscale 1.25 srpath sunfil.ras nsecs 7
   nibs 2859 ann gmtint anninc 5
   trpin 200 def .02 wiggle 0
   end
end
end
eof
xloadimage -r 90 sunfil.ras &


    A 3 trace mix does wonders for reducing the noise in the
water column.   Try it!  (see the Avon example for other things to try).
sioseis << eof
procs diskin stack mix filter plot end
diskin
   ntrgat 4
   ipath file1.segy ntodo 2000 end
end
filter
   ftype 0 pass 20 150 dbdrop 48 end
end
mix
   weight 1 2 1 end
end
agc
   winlen .5 end
end
plot
   vscale 1.25 srpath sunfil.ras nsecs 7
   nibs 2859 ann gmtint anninc 5
   trpin 200 def .02 wiggle 0
   end
end
end
eof
xloadimage -r 90 sunfil.ras &


    You may want to extract smaller portions of the data by
using diskin parameters    fgmt, lgmt, fday, lday
e.g.
 diskin 
    ntrgat 4 fday 253 lday 253 fgmt 1645 lgmt 1715 
    ipath file1.segy end 
 end 

    There are several programs that convert Sun rasterfiles
to PostScript, though I don't like any on the Sun (suntops and
ras2ps), so I use GraphicConverter on the Mac.  ImageMagik might
work.  Some people are using sioseis' process grdout and GMT.

    You may want to create wallpaper on the HP plotter.  You must
generate a SIOSEIS plot file (plot parameter opath) and then convert
it into an HP rasterfile using program sio2hp.  Then lpr it.

    Have fun guys!
Return to SIOSEIS examples.          Go to the list of seismic processes.          Go to SIOSEIS introduction.