Re: Surface Attributes from 2D seismic
I beleive your problem is, your using a surface. Surfaces only can be used in 3D cubes, while interpretation horizons can be used for attribute extraction on 2D lines. (the naming of the process and error message in P2009 is a little misleading).
So run the surface attribute extraction using the interpreted horizon (from your interpretatin folder in your seismics folder). Make sure you select the vintage you did the interpetation on and is the same as the seismic vintage you are extracting from. No run it and it adds an attribute to the specific interpretation horizons vintage.
Make a surface using this vintage (should have high peaks and look like a dissaster, but don';t worry). Now use the calculator to appoint this data set to a new attribute on the origianl surface created from the interpreted horizon (the one containing TWT)..
that's all... Hope this is clear, don;t hesitate to ask more details.