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problem with OFFREG module Link to this post

Dear Keleigh Jones,
I have a problem with the OFFREG module in my flow, I captured an image about it and I also sent you my job flow. Actually I knew the problem which is in shot id 220, there is just 3 live channels and OFFREG module cannot interpolate the trace spacing. I tried to solve the problem by reduce the NTR_INTERP from 5 to 3 and ORDER from 4 to 2, but it gave weird and not valuable result (like in one image).
Could you recommend me how to solve it and can make the job run ?
Thank you.

Re: problem with OFFREG module Link to this post

Hi Quang,

Unfortunately you will need to remove all low fold shots prior to OFFREG, and this probably generally just a good idea for the processing anyway, although worth confirming that the shots are lowfold during acquisition and not as a result of something processing related, although from the example dataset I have I think it''s likely to be as a consequence of the CDP binning defined in ADDGEOM.

Anyway I have attached an updated 03_QC_SP_DUSWELL_TAUPDecon flowto to the email I sent you, which has a RENUMBER/HDRMATH/IFNOT/TREMOVE/ENDIF loop to discard any lowfold shots present in the input data prior to OFFREG, I suspect I did not encounter this problem as I had rejected all of the shots before SP 404 as being recorded when the ship was transitting onto the line and the level of feather was extreme so were of no value to the processing, I would still strongly suggest that this is the best solution as any traces contributing to CDP's from these shots (1-404) will not behave hyperbolically in the CDP domain and will cause problems in the processing sequence.

So to reiterate for line 201 I would recommend only processing SP's 404 to 2804 inclusive as shots outside this range are showing extreme levels of feather from the boat transitting on and off the line.

Hope this helps.

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