Demo for SUVEL2DF   

Instructions for running the demo:

Type: 

Velsynti     to make synthetic anisotropic data and display the semblance plot.

(The synthetic data is made with "susynlvfti".)

The semblance plot is the contour map. To pick the horizontal
and NMO velocities, place the cursor on the peak of the ridge,
representing the region of maximum semblance and type the letter 's'
to save the picked value. Then type:  q   to quit the program.
The file:  picked.values  will contain two values of approximately:

 2184 2001

These numbers are the horizontal and NMO velocities respectively. 
We only have a single reflector in this example, but if you
had more reflectors, and estimated other values of horizontal
and NMO velocities from the same CMP then you could
build a vertical velocity model and determine the degree of
anisotropy  for anisotropic processing.

The parameter eta, which is a measure of anisotropy, is given by
eta=0.5*(Vh^2/Vnmo^2 - 1)= 0.96 in this case.
If you notice the forward modeling using susynlvfti, you will realize
that epsilon=0.1 and delta=0 and as a result the real model eta=0.1 and
it is close to the estimated one.  The relation between eta and 
epsilon is as follows: eta=(epsilon-delta)/(1+2 delta).
Because delta=0 in the model then eta should equal epsilon and it was
close difference 0.04.  Also, the estimated Vnmo=2001 m/s is
close to the modeled one of 2000 m/s.

John Stockwell	 | jstockwe@mines.edu
Center for Wave Phenomena (The Home of Seismic Un*x)
Colorado School of Mines
Golden, CO 80401 | http://www.cwp.mines.edu/cwpcodes
voice: (303) 273-3049  |    fax: (303) 273-3478.
