SIOSEIS scripts to remove the ship heave and filter agc and plot.

       Heave Removal Using a User Defined Water Bottom


This method of heave removal uses the difference between
the automatic first break pick and a user defined water bottom.

This procedure has to be done in two steps because process
WBT has to be used twice. 

1)  Step 1 uses process WBT to put the user defined water bottom
    time in SEG-Y header word 50.  Process HEADER is used to
    make process WBT think the data are sorted by RP rather
    than by SHOT.
    It is conceivable that a multibeam system such as Hydrosweep
    or SeaBeam put the water depth in the SEG-Y header automatically
    rather than the user,

2)  Step 2 uses the automatic picker in process WBT to pick the
    first arrival and put it in SEG-Y header word 59.  Process
    HEADER then puts the difference between header word 59 and 50 
    into SEG-Y header word 60.  Process SHIFT then shifts each
    trace according to the shift in SEG-Y header word 60.

sioseis << eof1
procs diskin header wbt diskoa end
diskin
   fno 469 lno 1475 allno no set .190 .240
    ipath L001_001.anal end
end
header
  fno 0 lno 999999 l6 = l3  ! make the rp no the same as the shot no
  end
end
wbt
  489 .194
  969 .194
 1219 .195
 1469 .197
end
diskoa
   opath L001_001.wbt1 end
end
end
eof1

sioseis << eof2
procs diskin filter wbt header shift agc plot end
diskin
   ipath L001_001.wbt1 end
end
filter
   fno 1 lno 99999 pass 500 2000 ftype 0 end
end
agc
   winlen .01 end
end
wbt
   index 59 solrat 4 ses .190 .193 sel .22 .23 end
end
header
   fno 0 lno 99999 r60 = r50 - r59 end
end
shift
   fno 0 lno 99999 indices r60 end
end
prout
  indices l3 l4 r50 r59 r60
   fno 1 lno 99999 ftr 1 ltr 99999 end
end
plot
   wiggle 0  ann gmtint anninc 1
   trpin 150 def .008  tlines .001
   srpath sunfil
  nibs 2859 nsecs .04 vscale 75.75758
   end
end
end
eof2