Posted on July 01, 2019
I hope that this note finds you very well. All is well on this end: very busy and very happy.
There is a three day SEG/KOC Workshop: “Seismic Multiples –the challenges and the way forward” to be held Dec. 3-5, 2019 in Kuwait City Kuwait.
I am deeply honored to have received an invitation (from the SEG/KOC workshop Chair Dr. Adel El-Emam of the Kuwait Oil Company on behalf of the Workshop Organizing Committee) as a Workshop participant and a Key-note presenter. Please see the links below.
Given this wonderful opportunity, I thought to share a few items and ideas that are relevant to this Workshop topic and hopefully you will find interesting and worthwhile.
I have divided this note below into three sections: Part I a new, clarifying and comprehensive perspective on primaries and multiples, -and then within that new comprehensive framework, what is the resulting priority and recent progress and open issues in Part II on multiples, and Part III on primaries.
I look forward to staying in touch. Warmest and very best regards,
For the new and clarifying perspective , please see the paper in the first attachment and the video presentation in the link below . That paper and video presentation resulted from an invitation received from Ecopetrol to write a journal article and to present a key-note address for the special event: Science, Technology and Future (CT& F) Special Edition on Seismic Migration and Inversion of the CT&F Journal on December 9, 2018 in Bogota Colombia.
The title of the attached article and the video presentation is :
‘Direct and indirect inversion and a new and comprehensive perspective
on the role of primaries and multiples in seismic data processing for structure determination and amplitude analysis’ .
I hope that you find the attached article, and the video presentation to be worthwhile, informative and interesting. The video begins by asking ‘Why do we need a new perspective?’ ‘What exactly is new?’ ‘And what are the practical benefits and value -and resource allocation consequence, and seismic E&P research strategy implications ?’
(1) The key business driver behind M-OSRP sponsorship
(2) The three pronged strategy and processing advances needed for effective on-shore and OBS multiple removal.
(3) On shore separate prediction of reflection data and ground roll , without filtering, without FWI, without damaging either the ground roll or reflection data, and without any subsurface information.
(4) A comparison of SRME and ISS free surface multiple elimination(FSME) - and when each is the appropriate tool box choice and when the ISS FSME is needed.
(5) A new embryonic concept and candidate criteria for adaptive subtraction , when free surface multiples interfere with other events and the energy minimization criteria in invalid. In our view ( even when in principle the predictor is an eliminator, with the correct time and amplitude) an adaptive subtraction step recognizes that our physics is never complete, and that its useful to provide a channel for the difference between the real world of the seismic experiment and the assumptions behind our assumed physical models and methods. The adaptive criteria ought to derive as a property of the prediction algorithm, always aligns with the latter , while allowing a channel for beyond the assumed physics and assumptions within algorithms.
(6) A multi-D ISS ( inverse scattering series) internal multiple elimination- and a comparison with the ISS internal multiple attenuator plus adaptive subtraction- and separately , accommodating primaries and internal multiples as input in the distinct ISSIMA and ISS IME algorithms.
In the third attachment ( for your possible interest) please find the slides of a key-note presentation in December 2018 at the SEG/KOC Workshop focusing on “Defining and Addressing On-Shore Challenges” .
In the first link below there is a menu to select videos with synced slides on these topics and other projects within our program e.g. Q compensation without knowing , estimating or determining Q( the latter topic belongs in Part III). The second link complements the first link, proving added perspective and documenting program delivery and plans. There are also five attachments with one for each of the above five topics related to multiples. Details and background and tutorials for part II and part III can be found in the these two links
The four attachments and the two links below provide a sample of progress and advances in processing primaries-the two links contain documents and videos providing tutorials, detailed technical discussion, differential added value and impact.
Ecopetrol invited paper for Special Issue on Seismic Migration and Inversion-ABWeglein-19-01-09.pdf
ISSIMA_2 accommodating primaries and internal multiples in ISS IMA.pdf
Weglein_etal_SEG2016_The first migration method that is equally effective for all acquired frequencies for imaging and inverting at the target and reservoir.pdf