Dr. Arthur B. Weglein holds the Hugh Roy and Lillie Cranz Cullen Distinguished University Chair in Physics at the University of Houston. He is a professor in the Department of Physics and the Department of Earth and Atmospheric Sciences. Prof. Weglein is the Director of the Mission-Oriented Seismic Research Program, a research consortium supported by the major oil and service companies in the world. Dr. Arthur B. Weglein served as the SEG Distinguished Lecturer in 2003, and was awarded the SEG’s Reginald Fessenden award in 2010. In 2008 he received the Distinguished Townsend Harris Medal from the City College of the City University of New York for his contributions to exploration seismology. He is also the co-author( with Bob Stolt) of a two volume graduate textbook on “Seismic Imaging and Inversion” published in 2012 by Cambridge University Press. In 2016, Weglein received the Maurice Ewing Medal, the SEG’s highest honor and award.

Arthur Weglein selected as Co-Editor-in-Chief of the Journal of Seismic Exploration

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Dear Colleagues and Friends,

I hope that this note finds you very well.

For your possible interest , please find two presentations in the link below.

The shorter one is   “A Keynote address at the SEG/KOC Workshop in Kuwait on November 28-30, 2023”and the longer video presentation is titled ” A Perspective on Advances and Challenges in Seismic Exploration(2024)” .

There are different topics in the shorter and longer video presentations that (taken together)I hope you find informative, interesting, and worthwhile.

http://mosrp.uh.edu/news/weglein-a-perspective-on-advances-and-challenges-in-seismic-exploration-2024

The link above also contains the slides of these two video recordings and the papers cited therein.

The longer presentation provides “ A Big Picture” with a more detailed and comprehensive seismic perspective.  I look forward to staying in touch.

Warmest best wishes for the Winter Holiday Season and for the New Year,

As ever,

Arthur

Below please find links to the individual presentations. Thanks.

The Shorter presentation is the one given at the SEG/KOC Workshop on November 28, 2023, in Kuwait city, Kuwait.

https://www.youtube-nocookie.com/embed/ryK3jRcWTio?playlist=ryK3jRcWTio&autoplay=1&iv_load_policy=3&loop=1&start=

Below please find the Longer presentation, that complements and goes beyond the Keynote address (above), for a more detailed and comprehensive perspective- including a very

succinct view of where we have been, where we are and where we might be soon ( twenty years from now).

https://www.youtube-nocookie.com/embed/Kca8BpT39pk?playlist=Kca8BpT39pk&autoplay=1&iv_load_policy=3&loop=1&start=

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Weglein invitation as the Keynote Speaker for the 2022 SEG Post-convention Workshop

https://uh.edu/nsm/physics/news-events/stories/2022/0420-seg-keynote.php

Dear Colleagues and Friends,

I hope that this note finds you very well. I look forward to staying in touch.

Warmest best wishes,

Arthur

http://www.mosrp.uh.edu/people/faculty/arthur-weglein

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Dear Colleagues and Friends,

I hope that this note finds you very well. All is well on this end: very busy and very happy.

In the first link below, please find a small selection of recent Keynote Addresses ( without ads) at International Conferences and Workshops.

• A small selection of M-OSRP videos without ads

The second link (below) contains a broader set of publications and invited International Keynote presentations.

http://www.mosrp.uh.edu/people/faculty/arthur-weglein

And the last item in the Featured Links section in the link above is a note ( please see the link below)sent to our stakeholders, and sponsors,

and the M-OSRP Advisory Board ( in 2013).

• M-OSRP update: For your possible interest, resending a 2013 note to the M-OSRP Advisory Board

I hope that you find these items to be interesting, informative, and worthwhile. I look forward to staying in touch.

Warmest best regards,

Arthur B. Weglein

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Dear Colleagues and Friends,

For your possible interest, please find in the two links below, soon to appear publications, with associated key-note presentations and a sampling of recent progress and advances. I look forward to staying in touch.

Link 1: http://www.mosrp.uh.edu/news/two-papers-to-appear-in-jse-in-february-2022

Link 2: http://www.mosrp.uh.edu/news/m-osrp-a-sample-of-recent-advances-and-progress-february-2022

Warmest and very best regards,

Art

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Dear Sponsors, Colleagues and Friends,

I hope that this note finds you very well.
Below for your possible interest, please find the Abstract for a presentation at the

82nd EAGE Conference & Exhibition 2020 8-11June 2020, Amsterdam, The Netherlands- post-convention Workshop on Multiples, Abstract for an Invited Presentation

Warmest best wishes for the New Year,
Arthur

Multiples: towards a toolbox perspective on assumptions, challenges and options (an Invited Presentation)
Arthur B. Weglein1, Jing Wu2, Frederico Xavier de Melo2 1M-OSRP/Physics Department/University of Houston 2WesternGeco/Schlumberger

Introduction

All seismic methods make assumptions; when the assumptions are satisfied, methods are effective, and when assumptions are violated, the methods can have difficulty and can fail. Seismic challenges arise when the assumptions behind the algorithm are violated. The three links provided at the end of this Abstract provide: (1) a more extensive and detailed version of this Abstract with a context, motivation and perspective (and the references cited within this abstract) and (2) the various types of assumptions behind seismic processing algorithms.

They are all important. For example, a seismic processing method is not an isolated entity, but rather a link in a sequence of processing steps. All the earlier steps in the chain, are important assumptions, prerequisites and requirements for the effectiveness of later steps.

A critically important assumption for a given link in the chain is the need for subsurface information. The industry trend to deep and complex offshore and onshore plays made the need for adequate subsurface information increasingly difficult or impossible to satisfy, and that inability r emains the situation today. That reality drove the interest in developing methods that did not need to know, to estimate or to determine subsurface information.

Removing the need for subsurface information.

G. Berkhout (1985) and E. Verschuur (1991), pioneered and developed SRME , an algorithm that provided an approximate prediction of the phase and amplitude of free surface multiples, without subsurface information, and independent of earth model type. To address the approximate nature of its prediction it called upon an energy minimization adaptive subtraction to remove the multiples. It is the method of choice for removing free surface multiples that are isolated and not proximal to, or interfering with, other events.

The inverse scattering series (ISS) free surface multiple elimination ( ISS FSME) (Carvalho et al. 1992) algorithm and the ISS internal multiple attenuation (ISS IMA) (Weglein et al. 2003) and ISS internal multiple elimination (ISS IME) (Zou et al. 2019) algorithms taken together, represent the high water mark of current multiple removal capability. They remove all multiples, and can automatically accommodate specular and non-specular reflectors, i nc l u di n g curved reflectors, diffractive reflectors, and pinch-outs, without (knowing, estimating or determining) any subsurface information, or any knowledge of the generators of the multiples. They are the only methods with that set of capabilities. The ISS FSME is the method of choice when a free surface multiple is proximal to or interfering with another event, Chao Ma et al (2018). SRME for FS multiples and ISS IMA have become industry standards for the following two reasons – they do not require any subsurface information or interpreter intervention. Figure 1 (from Zou et al., 2019) shows a comparison of ISS IMA and ISS IME for a model where the base salt primary interferes with an internal multiple generated at the water bottom. The ISS IMA plus adaptive damaged the base salt primary, whereas the ISS IME removed the internal multiple without damaging the base salt primary.

Marchenko-based methods towards internal multiple removal have received substantial and positive interest over the recent years. There are various approaches within the Marchenko portfolio, each with a different set of features and requirements that may suit a given multiple contamination problem, if their assumptions are met.

From two different and important representative Marchenko approaches presented at the recent SEG/KOC Workshop on Multiples Dec. 3-5, 2019, by Wapenaar et al. (2019) and Dukalski et al (2019), we understand that when a full re-datuming of source and receivers is part of the method, a smooth migration like velocity model is needed. Alternatively, when the method is performed from the seismic experiment recording surface, a virtual boundary defining the multiple generating formations and target ones is required. Although the boundary is virtual, it is required to reside beneath a known and well located physical reflector, requiring prior knowledge and information about the subsurface. This requirement can be loosely interpreted as a generalized form of the Jakubowicz (1998) method and relates to early internal multiple removal concepts by Berkhout. For any choice of virtual boundary, certain multiples will be removable and others will not. The paper by Zhang et al. (2019) is an advance within the Marchenko umbrella, that does not require a virtual surface, showed encouraging results, and explicitly points out several assumptions made in the method. Among the assumptions pointed out is that the data and the multiples are assumed to arise from a reflectivity model of the subsurface, a specular reflection model, valid for planar reflectors and will not accommodate curved and diffractive multiple generators. Another assumption is that later-arriving primaries are coming from deeper depths. We know that shallow primary events can have a longer arrival time than a deeper primary, especially at far offset ranges. In such cases, the method assumption is not met, leading to a need of complementary methods to help address the internal multiple contamination issue at far offset. The distinct ISS methods for eliminating free surface multiples, and for attenuating or eliminating internal multiples make none of the assumptions described above for Marchenko methods.

Many factors go into deciding the appropriate toolbox choice for a given play. No method is the cost- effective choice under all circumstances. When a method like, e.g., Radon de-multiple, (that assumes a one-D earth, and requires sufficient move-out differences and a velocity model) is effective, it can be the cost-effective toolbox choice. We encourage collaborative research to understand under what circumstances, e.g., the Marchenko approaches and ISS methods might be the indicated and appropriate toolbox choice for removing multiples. In our view, the function of research is to increase the options in the seismic tool box, providing: (1) effectiveness under a broader set of circumstances, and (2) a guide for when a particular method would be the cost-effective and appropriate choice.

For dealing with onshore challenges, Weglein (2013) proposed a three-pronged strategy. The development of new onshore preprocessing and processing methods that do not need near surface information would be an important step and advance towards realizing that strategy. In this presentation we will cover: (1) a recent advance in the removal of the need for near surface information, (Weglein 2020a) and (2) a new and first multi-D ISS algorithm for eliminating higher order internal multiples (Weglein 2020b).

Acknowledgements

We thank the M-OSRP sponsors for their encouragement and support and Schlumberger for their support and permission to publish. And we thank Dr Jim Mayhan for his assist in preparing this abstract. We thank the organizers of the 2020 EAGE Workshop on Multiples for the invitation to present.

An extended and more detailed version of this 2020 EAGE Abstract, including references, is available in the two links below

http://www.mosrp.uh.edu/news/m-osrp-news-2020-eage-workshop-on-multiples-invited-talk , https://bit.ly/3byirFZ

Also relevant for context and perspective is the video below of the key-note address that Weglein presented at the 2019 SEG/KOC workshop on Multiples in Kuwait

“A New Perspective on Removing and Using Multiples”, Pre-recorded keynote address for the SEG/KOC Workshop Seismic Multiples – the Challenges and Way Forward. ( https://youtu.be/sD89_418h1A )

http://www.mosrp.uh.edu/news/m-osrp-news-2020-eage-workshop-on-multiples-invited-talk