Prestack time migration using focus

[RRM]

Hi,

What are the steps to perform pre-stack time migration after NMO in focus software( Paradigm)?

Following are the steps I have followed till NMO:
1.Time gathers loading
2.Band pass filtering
3.Muting
4.Band limited spiking deconvolution
5.Velocity determination
6.NMO

Any kind of help is highly appreciated.

[GuyM]

If you want software specific help ask the software helpdesk...

If you want to know about seismic data processing sequences then I can help you there.

So - to start with

1. are you talking about land or marine data ?
2. when you say "time gathers" what is the full processing sequence applied so far ?

If this is land data - STATICS are key
If its marine data - DEMULTIPLE is key

You might also need to address things like coherent noise (ground roll, refractions, other linear noise) and random noise.
You also don't talk about amplitude recovery...

The critical thing with PreSTM is that you can form the data into offset planes (or cubes) that are reasonably complete and don't have too many gaps. That might mean offset regularization and so on (I've only used GeoDepth, but that has the preSTM, included)

I work through a complete 2D marine processing sequence here :
http://seismicreflections.globeclaritas ... ample.html

I'm working up land processing tutorial along the same lines at the moment - hopefully that will become a new blog series as well before too long.