SUKDMIG2D - Kirchhoff Depth Migration of 2D poststack/prestack data

sukdmig2d infile= outfile= [parameters]

Required parameters:
infile=stdin file for input seismic traces
outfile=stdout file for common offset migration output
ttfile file for input traveltime tables
The following 9 parameters describe traveltime tables:
fzt first depth sample in traveltime table
nzt number of depth samples in traveltime table
dzt depth interval in traveltime table
fxt first lateral sample in traveltime table
nxt number of lateral samples in traveltime table
dxt lateral interval in traveltime table
fs x-coordinate of first source
ns number of sources
ds x-coordinate increment of sources

Optional Parameters:
dt= or from header (dt) time sampling interval of input data
ft= or from header (ft) first time sample of input data
dxm= or from header (d2) sampling interval of midpoints
fzo=fzt z-coordinate of first point in output trace
dzo=0.2*dzt vertical spacing of output trace
nzo=5*(nzt-1)+1 number of points in output trace ",
fxo=fxt x-coordinate of first output trace
dxo=0.5*dxt horizontal spacing of output trace
nxo=2*(nxt-1)+1 number of output traces ",
off0=0 first offest in output
doff=99999 offset increment in output
noff=1 number of offsets in output ",
fmax=0.25/dt frequency-highcut for input traces
offmax=99999 maximum absolute offset allowed in migration
aperx=nxt*dxt/2 migration lateral aperature
angmax=60 migration angle aperature from vertical
v0=1500(m/s) reference velocity value at surface ",
dvz=0.0 reference velocity vertical gradient
ls=1 flag for line source
jpfile=stderr job print file name
mtr=100 print verbal information at every mtr traces
ntr=100000 maximum number of input traces to be migrated
npv=0 flag of computing quantities for velocity analysis
...if npv>0 specify the following three files:
tvfile=tvfile input file of traveltime variation tables
tv[ns][nxt][nzt]
csfile=csfile input file of cosine tables cs[ns][nxt][nzt]
dataout1=dataout1 file containning additional migration output
with extra amplitude

Notes:
1. Traveltime tables were generated by program rayt2d (or other ones)
on relatively coarse grids, with dimension ns*nxt*nzt. In the
migration process, traveltimes are interpolated into shot/gephone
positions and output grids.
2. Input seismic traces must be SU format and can be any type of
gathers (common shot, common offset, common CDP, and so on). ",
3. Migrated traces are output in CDP gathers if velocity analysis
is required, with dimension nxo*noff*nzo. ",
4. If the offset value of an input trace is not in the offset array
of output, the nearest one in the array is chosen.
5. Memory requirement for this program is about
[ns*nxt*nzt+noff*nxo*nzo+4*nr*nzt+5*nxt*nzt+npa*(2*ns*nxt*nzt
+noff*nxo*nzo+4*nxt*nzt)]*4 bytes
where nr = 1+min(nxt*dxt,0.5*offmax+aperx)/dxo.
6. Amplitudes are computed using the reference velocity profile, v(z),
specified by the parameters v0= and dvz=.
7. Input traces must specify source and receiver positions via the header
fields tr.sx and tr.gx. Offset is computed automatically.


Author: Zhenyue Liu, 03/01/95, Colorado School of Mines

Trace header fields accessed: ns, dt, delrt, d2
Trace header fields modified: sx, gx