Finite Difference Forward Modelling examples



1) c_hypcvel:  Generate a constant velocity hyperbola.

sioseis << eof
procs syn filter diskoa fdfmod prout diskob end

syn
   fno  1 lno 49  ntrcs 1 secs 3.0 tva 3.1 2500 1 end
   fno 50 lno 50  ntrcs 1 secs 3.0 tva .3 2500 1 .7 2500 1  1.0 2500 1 1.3 2500 1 1.8 2500 1 end
   fno 51 lno 100 ntrcs 1 secs 3.0 tva 3.1 2500 1 end
end                    

filter
    pass 10 20 end
end

diskoa
    opath impulsecvel.segy
    fon 1
  end
end

fdfmod
   nx 102 bpad 1 epad 1 
   opad no maxsam 751
   dx 25 maxdip .001 
   path scratch
   vtp 2500 0.0 2500 3.0 
   tsteps 3.00 .1                           
   end
end

prout
  fno 1 lno 99999 ftr 1 ltr 99999
  end
end

diskob
  opath impulsecvel.fddiff fon 1
  end
end

end





2) c_hypvlat:  Generate a hyperbola with laterally varying velocity.

sioseis << eof
procs syn filter diskoa fdfmod prout diskob end

syn
   fno  1  lno 49   ntrcs 1 secs 3.0 tva 3.1 1500 1 end
   fno 50  lno 50   ntrcs 1 secs 3.0 tva  0.5 1500 1   1.0 2000 1   1.5 2500 1  end
   fno 51  lno 149  ntrcs 1 secs 3.0 tva 3.1 1500 1 end
   fno 150 lno 150  ntrcs 1 secs 3.0 tva 0.25 1500 1   0.75 2000 1   1.25 2500 1 end
   fno 151 lno 249  ntrcs 1 secs 3.0 tva 3.1 1500 1 end
   fno 250 lno 250  ntrcs 1 secs 3.0 tva 0.50 2000 1  1.0 2500 1 end
   fno 251 lno 300  ntrcs 1 secs 3.0 tva 3.1 1500 1 end
end                    

filter
    pass 10 20 end
end

diskoa
    opath impulsevlat.segy
    fon 1
  end
end

fdfmod
   nx 302 bpad 1 epad 1 
   opad no maxsam 751
   dx 25 maxdip .001 
   path scratch 
   fno 1   tsteps 3.00 .100 vtp 1500 0.500 2000 1.000 2500 1.500
3000 3.0 end
   fno 100 tsteps 3.00 .100 vtp 1500 0.500 2000 1.000 2500 1.500
3000 3.0 end
   fno 110 tsteps 3.00 .100 vtp 1500 0.250 2000 0.750 2500 1.250 
3000 3.0 end
   fno 200 tsteps 3.00 .100 vtp 1500 0.250 2000 0.750 2500 1.250 
3000 3.0 end
   fno 210 tsteps 3.00 .100 vtp 2000 0.500 2500 1.000 3000 3.000 end
   fno 300 tsteps 3.00 .100 vtp 2000 0.500 2500 1.000 3000 3.000 end
end

prout
  fno 1 lno 99999 ftr 1 ltr 99999
  end
end

diskob
  opath impulsevlat.fdfmod fon 1
  end
end

end
eof





3) c_rms.fddiff:  Generate a hyperbola with rms velocity

sioseis << eof
procs syn filter diskoa fdfmod prout diskob end

syn
   fno  1 lno 49  ntrcs 1 secs 3.0 tva 3.1 1500 1 end
   fno 50 lno 50  ntrcs 1 secs 3.0 tva .5 1500 1  1.0 2000 1 1.5 2500 1 2.0 2750 1 end
   fno 51 lno 100 ntrcs 1 secs 3.0 tva 3.1 1500 1 end
end                    

filter
    pass 10 20 end
end

diskoa
    opath impulserms.segy
    fon 1
  end
end

fdfmod
   nx 102 bpad 1 epad 1 
   opad no maxsam 751
   dx 25 maxdip .001 
   path scratch
   vtp  1500 0.500 2000 1.000 2500 1.500  2750 2.00
   3000 3.00 
   tsteps 3.00 .100                           
   end
end

prout
  fno 1 lno 99999 ftr 1 ltr 99999
  end
end

diskob
  opath impulserms.fdfmod fon 1
  end
end

end
eof




4) /c_mod.dip.refl:  Generate a hyperbola with dip.

sioseis << eof
procs syn filter diskoa fdfmod prout diskob end

syn
   fno  1 lno 35   ntrcs 1 secs 2.000 tva 2.100 1500 1 end
   fno 36 lno 36   ntrcs 1 secs 2.000 tva 1.260 1500 1 end
   fno 37 lno 37   ntrcs 1 secs 2.000 tva 1.268 1500 1 end
   fno 38 lno 38   ntrcs 1 secs 2.000 tva 1.276 1500 1 end
   fno 39 lno 39   ntrcs 1 secs 2.000 tva 1.284 1500 1 end
   fno 40 lno 40   ntrcs 1 secs 2.000 tva 1.292 1500 1 end
   fno 41 lno 41   ntrcs 1 secs 2.000 tva 1.300 1500 1 end
   fno 42 lno 42   ntrcs 1 secs 2.000 tva 1.308 1500 1 end
   fno 43 lno 43   ntrcs 1 secs 2.000 tva 1.316 1500 1 end
   fno 44 lno 44   ntrcs 1 secs 2.000 tva 1.324 1500 1 end
   fno 45 lno 45   ntrcs 1 secs 2.000 tva 1.332 1500 1 end
   fno 46 lno 46   ntrcs 1 secs 2.000 tva 1.340 1500 1 end
   fno 47 lno 47   ntrcs 1 secs 2.000 tva 1.348 1500 1 end
   fno 48 lno 48   ntrcs 1 secs 2.000 tva 1.356 1500 1 end
   fno 49 lno 49   ntrcs 1 secs 2.000 tva 1.364 1500 1 end
   fno 50 lno 50   ntrcs 1 secs 2.000 tva 1.372 1500 1 end
   fno 51 lno 51   ntrcs 1 secs 2.000 tva 1.380 1500 1 end
   fno 52 lno 52   ntrcs 1 secs 2.000 tva 1.388 1500 1 end
   fno 53 lno 53   ntrcs 1 secs 2.000 tva 1.396 1500 1 end
   fno 54 lno 54   ntrcs 1 secs 2.000 tva 1.404 1500 1 end
   fno 55 lno 55   ntrcs 1 secs 2.000 tva 1.412 1500 1 end
   fno 56 lno 56   ntrcs 1 secs 2.000 tva 1.420 1500 1 end
   fno 57 lno 57   ntrcs 1 secs 2.000 tva 1.428 1500 1 end
   fno 58 lno 58   ntrcs 1 secs 2.000 tva 1.436 1500 1 end
   fno 59 lno 59   ntrcs 1 secs 2.000 tva 1.444 1500 1 end
   fno 60 lno 60   ntrcs 1 secs 2.000 tva 1.452 1500 1 end
   fno 61 lno 61   ntrcs 1 secs 2.000 tva 1.460 1500 1 end
   fno 62 lno 62   ntrcs 1 secs 2.000 tva 1.468 1500 1 end
   fno 63 lno 63   ntrcs 1 secs 2.000 tva 1.476 1500 1 end
   fno 64 lno 64   ntrcs 1 secs 2.000 tva 1.484 1500 1 end
   fno 65 lno 65   ntrcs 1 secs 2.000 tva 1.492 1500 1 end
   fno 66 lno 100  ntrcs 1 secs 2.000 tva 2.100 1500 1 end
end                    

filter
    pass 10 45 end
end

diskoa
    opath diprefl.segy
    fon 1
  end
end

fdfmod
   nx 102 bpad 1 epad 1 
   opad no
   dx 25 maxdip .001 
   path scratch
   vtp 1500 0.0 1500 2.0
   tsteps 2.00 0.10
   end
end

prout
  fno 1 lno 99999 ftr 1 ltr 99999
  end
end

diskob
  opath diprefl.fdfmod fon 1
  end
end

end
eof