# Gaussian packet migration
# ~~~~~~~~~~~~~~~~~~~~~~~~~
#
# Calculating source-receiver coordinates, ray parameters
  MODEL='mar-mod.dat' 
  SRC='mgp-src.out'   REC='mgp-rec.out'   RPAR='mgp-rpa.out'
  X1SRC=8.   X2SRC=0. X3SRC=0.
  X1REC=12.  X2REC=0. X3REC=0.
  OSRC=3000. DSRC=25. OXRINI=425.  KOLPAR=2
  gprpar:

# Ray tracing from a given source
  SRC='mgp-src.out'  REC=' '              DCRT='mgp-crt1.dat'
  CODE='codep.dat'   RPAR='mgp-crt1.dat'  WRIT='mgp-wri.dat'
  CRTLOG='mgp-log.out'
  INIPAR=2  CRTSCRO='GP'
  crt:

# Calculating travel times and amplitudes of the incident wave field
# N1=751  N2=2301        D1=4   D2=4
  N1=151  N2=461   N3=1  D1=20  D2=20
 #N1=121  N2=369   N3=1  D1=25  D2=25
  NUM='mtt-num.out'  MTT='mtt-tt.out'
  AMP='mtt-apr.out'  AMP2D3=1.0
  mtt:

# Back-propagation of the wavefield from receivers 
# and computation of migrated sections
  SRC='mgp-rec.out'  DCRT='mgp-crt2.dat'  RPAR='mgp-rpa.out'
  INIPAR=3  INIE2=1.570796327
  crt:

# Discretization steps of the decomposed wavefield
  NX=96  DX=25. OX=0.  NT=750 DT=0.004 OT=0.
# Parameters
 #KAPPA=1.253314137  RELAMP=0.01  DTRAY=0.05 
  KAPPA=2.           RELAMP=0.1   DTRAY=0.05 
  N1MAX=751 N2MAX=2301  IXTZU=1 IXTZD=151 IXTZL=1 IXTZR=461
  gpmig:

# Plotting migrated sections
  N1=2301  N2=751  N3=1
  VREF=0.  CREF=0.166667  VMIN=-999999000000.0
  grdps: