SUINVZCO3D - Seismic INVersion of Common Offset data with V(Z) velocity
function in 3D
suinvzco3d outfile [optional parameters]
Required Parameters:
vfile file containing velocity array v[nz]
nz= number of z samples (1st dimension) in velocity
nxm= number of midpoints of input traces
ny= number of lines
Optional Parameters:
dt= or from header (dt) time sampling interval of input data
offs= or from header (offset) source-receiver offset
dxm= or from header (d2) sampling interval of midpoints
fxm=0 first midpoint in input trace
nxd=5 skipped number of midpoints (see note)
dx=50.0 x sampling interval of velocity
fx=0.0 first x sample of velocity
dz=50.0 z sampling interval of velocity
nxb=nx/2 band centered at midpoints (see note)
fxo=0.0 x-coordinate of first output trace
dxo=15.0 horizontal spacing of output trace
nxo=101 number of output traces ",
fyo=0.0 y-coordinate of first output trace
dyo=15.0 y-coordinate spacing of output trace
nyo=101 number of output traces in y-direction
fzo=0.0 z-coordinate of first point in output trace
dzo=15.0 vertical spacing of output trace
nzo=101 number of points in output trace ",
fmax=0.25/dt Maximum frequency set for operator antialiasing
ang=180 Maximum dip angle allowed in the image
verbose=1 =1 to print some useful information
Notes:
This algorithm is based on formula (50) in Geophysics Vol. 51,
1552-1558, by Cohen, J., Hagin, F., and Bleistein, N.
Traveltime and amplitude are calculated by ray tracing.
Interpolation is used to calculate traveltime and amplitude. ",
For each midpoint, traveltime and amplitude are calculated in the
horizontal range of (xm-nxb*dx, xm+nxb*dx). Velocity is changed by
linear interpolation in two upper trianglar corners whose width is
nxc*dx and height is nzc*dz. ",
Eikonal equation will fail to solve if there is a polar turned ray.
In this case, the program shows the related geometric information.
Offsets are signed - may be positive or negative. ",