# SeismicUnix - Finite Difference Migration [closed]

I'm trying to apply sumigfd on simple.su data which is used in the John Stockwell course in geophysical image processing - in the Migration chapter on page 85. I have not had any success because the vfile was not set up well. Even when I created a new vfile the problem persisits.

surange < simple.su

80 traces:

tracl    1 80 (1 - 80)
cdp      1 80 (1 - 80)
trid     1
ns       501
dt       4000


After this information I created a vfile using the instructions,

 makevel nx=80 nz=501 > cr
transp < cr n1=80 > ce

• Hi Liath, welcome to ES. At the moment it is very difficult to understand the question. Please refer to the help center to gain a better understanding of what constitutes a good question on this site in order to increase the chances it gets answered. Mar 1, 2016 at 9:00
• In addition to following the guidelines from the Earth Science help centre, you can improve your question by including the essential information for any question about software problems, i.e. detailed and unambiguous explanations of (1) what you did, (2) what you expected to happen, and (3) what actually did happen.
– Pont
Mar 8, 2016 at 19:02