UNIF2 - generate a 2-D UNIFormly sampled velocity profile from a layered
model. In each layer, velocity is a linear function of position.
unif2 < infile > outfile [parameters]
Required parameters:
none
Optional Parameters:
ninf=5 number of interfaces
nx=100 number of x samples (2nd dimension)
nz=100 number of z samples (1st dimension)
dx=10 x sampling interval
dz=10 z sampling interval
npmax=201 maximum number of points on interfaces
fx=0.0 first x sample
fz=0.0 first z sample
x0=0.0,0.0,..., distance x at which v00 is specified
z0=0.0,0.0,..., depth z at which v00 is specified
v00=1500,2000,2500..., velocity at each x0,z0 (m/sec)
dvdx=0.0 derivative of velocity with distance x (dv/dx)
dvdz=0.0 derivative of velocity with depth z (dv/dz)
method=linear for linear interpolation of interface
=mono for monotonic cubic interpolation of interface
=akima for Akima's cubic interpolation of interface
=spline for cubic spline interpolation of interface
tfile= =testfilename if set, a sample input dataset is
output to "testfilename".
Notes:
The input file is an ASCII file containing x z values representing a
piecewise continuous velocity model with a flat surface on top. The surface
and each successive boundary between media are represented by a list of
selected x z pairs written column form. The first and last x values must
be the same for all boundaries. Use the entry 1.0 -99999 to separate
entries for successive boundaries. No boundary may cross another. Note
that the choice of the method of interpolation may cause boundaries
to cross that do not appear to cross in the input data file.
The number of interfaces is specified by the parameter "ninf". This
number does not include the top surface of the model. The input data
format is the same as a CSHOT model file with all comments removed.
Example using test input file generating feature:
unif2 tfile=testfilename produces a 5 interface demonstration model
unif2 < testfilename | psimage n1=100 n2=100 d1=10 d2=10 | ...
Credits:
CWP: Zhenyue Liu, 1994
CWP: John Stockwell, 1994, added demonstration model stuff.