“Be ready for change,...the industry and geophysics will change dramatically.”

Biondo, let us begin by asking you tell us something about your educational qualifications and your work experience.

I got an Electrical Engineering degree in Milan at Politecnico di Milano, which is also my hometown, and then I came to Stanford University to get a Ph.D. in Geophysics. I got my Ph.D. in 1990, and after leaving Stanford I went to work for a company called Thinking Machines. Thinking Machines was a pioneer in the development of massively parallel computers. I went there because I felt that parallel computing was going to play a crucial role in seismic processing and imaging, and indeed I learned quite a bit. I left in ‘93 to start a company with a few colleagues. That company didn’t go anywhere. However, shortly after I co-founded a company that is still in business and growing, which is called 3DGeo Development. Slowly I got back working more and more with Stanford and here I am teaching full time at Stanford.

You got a masters degree in Electrical Engineering as you said from Milan, so how did you switch from Electrical Engineering to Geophysics? How did that decision come about?

To get a Master’s degree in Italy you need to have a thesis. My thesis advisor was Fabio Rocca. For the previous 10 years he had worked in seismic processing, and he got me excited about it – I did a thesis on seismic migration. Afew years earlier I had gone to Berkley for a summer session just to get an idea how American universities work, and I liked it. Putting the two things together I applied to Stanford for a Ph.D. in Geophysics. I was accepted and I went there.

Since you have come to the U.S., have you basically stayed at Stanford?

Stanford is a great place to work, and the Bay is a beautiful place to live. Also, my wife-to-be at the time didn’t want to leave the Bay area; we got married in ‘91. I went to Cambridge, Massachusetts for six months to work at Thinking Machines headquarters, and then came back to the Bay area.

Who have been some of your mentors?

I can think of three of them in different phases of my life. My dad was my first scientific mentor. He was a professor in bioengineering in Milan, and he showed me how interesting science could be, but also that it is always important to question authority, in science, as well as in life in general. Fabio Rocca was another important one. He taught me how much fun and enthusiasm you can have doing science. His enthusiasm and creativity are contagious and an example of the best way to get a young person excited with science.

The most important one is Jon Claerbout – as an advisor when I was a student, then as a supervisor when I started working back at Stanford, and now as a senior colleague. He taught me so many things, in Geophysics as well as in the general approach to research: paying attention to small details that may seem insignificant, but are often not; being open minded to what seismic data can teach us; really analyzing data without preconception and understanding what surprises data present and learning from them; being humble when looking at the real world and trying to learn from it. Those are things that are not obvious to students that don’t come from a geoscience background, like me.

What personal qualities do you think enabled you to achieve the professional status that you enjoy today? Is it hard work, ambition, or anything else? Do you also think you had a firm grounding in mathematical concepts that has kept you in good stead or is it something else?

Probably a lot of things together. Clearly, hard work is necessary; that is one thing that I am trying to teach my kids. It is not enough to be smart, or thinking to be smart, but you need to work hard and mostly work hard enhancing your skills because you can always learn, no matter how old or how successful you are. Never giving up is also important; in terms of both the bigger scale of a career and path in life or the smaller scale when there is something you were excited about that does not seem to work at first. For example, if one day you think about a new processing technique, but it does not work immediately. Don’t be taken aback – keep going and believe in what you are doing.

Another trait that probably helped me is being not afraid of trying new paths. I moved to a new country and I had no strong reason to leave the old country. I went from Electrical Engineering to Geophysics and then from Geophysics to work for a computer company. From there I started my own company and from that back to academia, so I think it is important to be open minded and try to catch opportunities in life when they come.

You mean the opportunity you got to work at Stanford, and with Jon Claerbout?

Certainly. You need to work hard in life but if you are not lucky you are not going to be successful. It was a unique chance to learn from Jon and to learn from all the fellow students. One of the wonderful things at Stanford is the environment among students and colleagues and there are so many great people to learn from and to grow while you learn.

As it is usually said, U.S. is the land of opportunities, newcomers arrive and are game for hard work. Do you think this is true in your case as well? When it comes to hard work, some individuals do believe that taking time off or holidaying is like a hurdle in their race against time. What is your belief on that?

Mine is slightly different in the sense that also I come from a different culture. Family and personal life are important, so I work very hard and am very focused, but nonetheless I find that you should never forget what maybe is the most important things in life, your family. And one must not forget to enjoy the one life you’ve got. This is one thing that is easy to say, but sometimes difficult to do in practice. My wife is professional as well, so we have two hard- charging professionals and finding the time and energy to enjoy family life can be a challenge, but it is crucial.

Tell us about Biondo the person, his likes, his dislikes, whatever you want to share with us?

Oh, I think that I am easy going, patient and open minded with respect to other people’s ideas, opinions and way of life. As I said, family is important to me. I do like sports, especially mountain biking. A t Stanford, we are lucky, there are beautiful hills. Have you ever been to Stanford?

No, I haven’t.

You should come and visit us. We don’t have high mountains as you have here, but the hills are much closer. They are only 5 minutes from my home. I can be up on a trail mountain biking and I do enjoy that. And when I get the time I enjoy reading. I am a fairly quiet person and simple. I like to explore, and that is probably one of the reasons why life brought me to America, so I like to go around the world. I like to travel, I mean with family and with work. That is one of the reasons why I am doing the DISC.

We are going to come to the DISC shortly. Tell us about your contributions to seismic imaging, as I know that this subject is very close to your heart.

In general terms I think that I helped the community to recognize that effective 3D prestack imaging can be substantially different than a simple generalization of 2D imaging methods. Because we acquire 3D data only on sparse and irregular geometries, the prestack imaging of 3D data presents different challenges and opportunities than the imaging of 2D data, which are usually recorded on more regular and complete geometries.

So far my two major contributions to seismic imaging have been the development of what is called azimuth move-out, or AMO, and that is a way of changing the acquisition geometry of the data. This does not make much sense on 2D data but it can be very useful for 3D data. Another contribution is common-azimuth migration, which is the first wave-equation migration that has been applied to large 3D data sets because it has a large (one or two orders of magnitude) advantage over more straightforward extensions of 2D methodologies. Again, you can only define common-azimuth migration in 3D.

More recently a student of mine, Paul Sava, and I have pushed the envelope on velocity estimation. We developed a practical method for using wavefield operators to update the velocity field instead of the conventional methods that use raytraced operators. The industrial application of this method is still some time in the future, but I believe that is coming. In the 80s Albert Tarantola in Paris and Bill Symes at Rice University had done some fundamental work on the use of wavefield operators for velocity estimation by developing the concepts of waveform inversion and differential semblance optimization. These methods stayed on the back burner for more than a decade, but now there are many other people in the community working on them. Hopefully, that will lead to major improvements in the imaging of data collected in complex areas.

What has been the most memorable moment in your professional life? Also, tell us about some of the successful landmarks in your geophysical career.

The most memorable moments are likely to be the private ones, such as when you know you are working on something important, and you begin to look at the first images coming out of the computer and they confirm what you had been hoping, maybe for months or years, and it actually works. As much as I enjoy the theoretical work, like manipulating equations, I get the real thrill from the application of the theory. I am an engineer at heart. I feel that ideas and theories are wonderful but I really get excited when science has an impact on the world.

Can you recall specific times that sort of thing happened?

Afew times when I was working on AMO and common azimuth migration, and also when I started working on wave-equation migration velocity analysis.

[Penny]: Can I ask one question? Dealing with students, do you think there is a difference between the students you would have from a science faculty than the ones from an engineering faculty?

Yes, absolutely. Our profession attracts a mix of the two kinds, and one of the wonderful things about our profession is that really you can be successful if you come from either side; contributions in our field can be very varied.

What are your aspirations for the future?

That is a tough one. As a teacher and a mentor, I hope I will succeed to help many more young students become professionals and help them to have a successful career and a fulfilled life. I cannot think of a better reward than doing that.

Of course, I have scientific aspirations as well. I hope that we will be able to get as nice images out of land data as we get out of marine data. This goal is strongly dependent on the data sampling and our ability to capture more of the propagating wavefield. The vast majority of the estimated world hydrocarbon reserves are on land. It would be great for our profession, and the future of the world energy supply, if we are able to get out of land data as much of the detail and information as we get out of marine data.

When it comes to the selection of a faculty member in a given department at the university, in your opinion what are the advantages/disadvantages of choosing an internal candidate over a candidate from outside? You have experienced this and so we would like your take on this.

The internal candidate must be able to convince people that he or she is the right person, more than an outsider. There is always a kind of prejudice about internal people, which is perfectly appropriate to avoid some kind of easy way in. I think it is crucial to have good quality control; large research universities like Stanford have stringent quality control mechanisms like public searches and extensive peer reviewing by outsiders. In my personal case, in 1999 there was a search for my position with a large number of applicants from the outside, some of them very strong ones. One of the dangers of coming from inside is to carry on in a “business as usual” mode. Again, in my specific case, the Stanford Exploration Project has been successful for about 35 years. However, to measure up to these past success, we need to adapt to the changing times in the way we operate, the way that we attract students, and the way that we ensure support from the industry, but at the same time we must maintain our traditional basic values and strengths. For example, we have many more students coming from outside North America and Europe than in the past. More of our current sponsoring companies are also not based in North America and Europe. The size of the companies is also changing. We had to live through the extensive restructuring and merging in the industry that happened five to ten years ago. In that period we were losing a couple of sponsors every year because of mergers. Now, our sponsors are not only geographically diverse, but also heterogeneous in size. We have a few smallish but fastgrowing high technology companies as well the more conventional big oil companies and big geophysical contractors.

In sports, people have a certain level of expectation from star players. When they don’t come up to that level the fans are disappointed. Going with that analogy, for a researcher or group that has contributed very effectively in the past, the expectations are high. When the contributions don’t come frequently, do you think the geophysical community is disappointed? I would like to hear your take on this. Do you think this happens in our field? What is required to keep meaningful contributions coming more often?

I like the sport analogy, but I see us, professors, being more like coaches than athletes. I think that we are successful as long as we teach our students to strive and try hard to come up with the next great idea. If they come out of Stanford with that mentality, even if they do not make their big contribution while they are at Stanford, then we are successful. Whereas the athlete that doesn’t score for half a season might feel that he has not accomplished anything, we can steadily contribute to the education of geophysicists. This goal can be achieved with fewer ups and downs, if you have the right students and provide them with the right environment. So a lot of my energy is dedicated to those two areas: to build and maintain a great environment and do my best to attract students with talent and will; then, I am almost tempted to say, the rest comes by itself.

You have the position of Associate Professor of Geophysics at Stanford University and you are also the codirector of the Stanford Exploration Project. Please tell us about the type of work that is being done in SEP and how many people are engaged in doing that.

At the moment there are about fourteen or fifteen students at SEP, two faculty members (Jon Claerbout and myself), and one senior research engineer, Bob Clapp. We develop and test new algorithms for processing and imaging seismic data. One crucial component of a SEP Ph.D. thesis is the testing of the main idea on 3D field data, because new ideas and insights come from testing your methods on field data. This focus on field-data verification lets us be more relevant to the practical application of imaging than most academic groups. On the other hands, it puts the burden on us to maintain a substantial computational facility because 3D seismic data, as we all know, is bulky and advanced imaging algorithms tend to be extremely computationally intensive. Students get trained not only in Mathematics and Geophysics but also in Computer Science. The development of these computational skills has proven to be extremely helpful to students’ careers when they join the seismic industry or academia.

Apart from Stanford, where is research on seismic imaging being carried out?

The good news recently is that oil companies are now back doing imaging research. At the end of the 90s research had became almost a bad word in oil companies. This attitude has changed. Large and medium-sized oil companies, large and small geophysical contractors, carry out research. There are also several academic groups that conduct first-rate research in seismic imaging. Successful academic consortia working on seismic are active at the Colorado School of Mines, University of Utah, CREWES here in Calgary and Delft in Holland. There are also smaller groups that are centres of excellence on some specific research topics. For example, here in Canada I would like to mention Mauricio Sacchi’s group at the University of Alberta in Edmonton, and Felix Hermann’s at the University of British Columbia.

At what point in their career do most students get interested in specialization – signal processing, imaging, or whatever the case may be?

I am afraid I am going to give you a partial answer because unfortunately at Stanford we have no undergrads in Geophysics. We do have, however, a large graduatestudent body in Geophysics of about 60 or 70, but no undergrads.

So none of them come from Stanford in the first place?

A few do. For example, I have now students that graduated in Physics from Stanford, but that is more the exception than the rule.

Is there a Geology undergraduate program?

Yes, there is a Geology undergraduate program, though it doesn’t feed into Geophysics much. In particular, the kind of Geophysics we do at SEP is more quantitative than most geologists are ready to take on.

That might explain why the Stanford graduate Geophysics program is more computationally focused rather than some others that also involve Geology more with Geophysics.

I think that is fair to say that. Another thing to keep in mind is that in our Department there is a strong non-industry-oriented component, that is, research that aims at improving our understanding of the Earth. The applied Geophysics is the minority. Counting the number of faculty members, we are less than forty percent of the Department. On the other hand, the majority of students in the department are in applied Geophysics.

But not seismology?

There are at least three academic seismologists in the department: one global seismologist, one expert in earthquake source mechanisms and one crustal reflection seismologist. We have collaborated with all of them. I encourage students that have interests outside of exploration seismology to take on projects that are not strictly in main SEP areas, for example using teleseismic data to image the subsurface. We also collaborate with other departments in the University, like the department of Petroleum Engineering and the Math Department.

You must be excited about your DISC tour. I believe you have just started. Could you comment on that?

The DISC tour is a wonderful opportunity and I have been fully enjoying it. I already have given seven of them, so tomorrow is the 8th. I am about 25% done. It is a great opportunity to meet colleagues around the world and to contribute in helping professionals and students to get more acquainted with modern imaging technologies. In all the cities I go, whenever practical, I try to visit a local university or a local company. For example, when I was in Beijing I went to visit Beijing University, where I gave a lecture to a large group of bright and eager students. When I visit companies I get the chance of looking at their seismic data and learning about the challenges to image their data. When I was in Southeast Asia last month, I was fortunate to visit three companies and learn a lot about seismic imaging problems in that region and I am looking forward to doing the same in other parts of the world. I see the DISC as a chance to learn as much to teach.

I think that the SEG and EAGE should support more of these kinds of activities. Almost everywhere I went I heard from the local membership that they would like to see more programs like the DISC. The Regional Distinguished Lectures program that SEG recently introduced is a move in the right direction. As we become much more global, these kinds of activities do really help.

[Penny]: I am going to put a plug in here. I hope you are going to tell the remaining 75% of your tour that the CSEG website has quite a few 45 minute or so speeches, which I think Satinder partly pioneered.

At the website we currently have more than 20 different webcast presentations, luncheon presentations, special sections presentations.

Do you have PowerPoint slides?

Well, if you look at the webcast, you will see the PowerPoint slides and a small video insert as well.

In 2004 you were given the SEG Reginald Fessenden Award for the development of the AMO. For the benefit of our members, I was going to ask you if you could just elaborate a little more on what AMO is and what is its importance?

AMO stands for “azimuth move-out” and is really a generalization of DMO to a case where you can synthesize prestack data from prestack data recorded with a different geometry. Whereas I initially envisioned AMO as a way of reducing the computational cost of 3D pre-stack imaging by reducing the amount of data before migration, now it is more used for improving the results of prestack imaging rather than for decreasing its cost. We can apply AMO to interpolate prestack data and regularize the acquisition geometry, or to extrapolate the data to extend the acquisition geometry, like along the cross- line offset for marine data. This kind of data extension has been successfully applied to improve the attenuation of challenging multiples in marine data.

AMO has its limitations like DMO has, that derive from the assumptions used in its derivations. It is important to keep that in mind so as not to ask it to perform tasks that it cannot do accurately.

Seismic imaging methods fall into two types: the integral Kirchhoff methods and the wavefieldcontinuation methods. While the former are intuitively easy to understand, the wavefieldcontinuation methods yield more accurate images of the complex subsurface structures. Having said this, please tell us, from a practical standpoint, which method is suited for which purpose?

I agree with your characterization. In my class tomorrow I will introduce migration using Kirchhoff methods because they are much more intuitive and then I will move on to the wavefield- continuation method. I think that a good criterion to keep in mind when choosing a migration method is not to use a method that is more complex than what the data and the velocity model require. For many datasets Kirchhoff methods can be substantially cheaper than wavefieldcontinuation methods and thus they are more effective. However, wavefield- continuation methods provide better images when the complexity of the overburden causes multipathing of the propagating wavefield. In these cases, we would be fools if we were to image our seismic data, which are so expensive to acquire, with sub-standard methods just to save a little computational cost. It is also important to remember that the wavefield-continuation migrations that we currently use, which are based on downward-continuation of the wavefields, are challenged when the goal is to image steeply dipping or overhanging reflectors. Kirchhoff methods may actually image these reflectors more accurately than downward-continuation methods. This limitation is the main reason why a lot of research effort these days is directed to the development of methods that propagate the wavefields using the two-way wave equation or the one-way wave equation in modified coordinate systems (e.g. tilted or elliptical coordinates).

What are the challenges that face us in the world of 3D seismic imaging? How do you think we will see them overcome?

We already discussed the challenges of land data. Another one is learning how to attenuate, or even better, use multiple reflections; not only surface related multiples but also internal multiples of different kinds, for example prismatic waves – events we see around salt bodies with complex geometries. At the research level we are making progress in identifying these events and conceptualizing imaging strategies, like the growing interest in interferometric imaging. However, we are very much at the beginning of that development and we are still very far from being able to use to our advantage all the events we record. Similarly, we are learning how to deal with imaging the elastic component of the wave-field. I think that it has been more than 20 years that useful imaging of elastic waves has been “just around the corner”, but in reality it has yielded useful results only in particular cases and geological conditions. There is still a lot of progress that can be done in the area of elastic imaging.

What problems or challenges are you working on currently?

I am mostly working on acoustic imaging in complex areas where the estimation of the velocity model is still “the” big problem. This is partially because of data quality and complex wave propagation but also because of the fundamental problem that the data do not contain sufficient information to define the velocity model. This limitation requires that we geophysicists work with the geologists to fill in the information gaps that the data have. This cooperation is a challenge both in the academic and R&D world as well as in daily processing of seismic data.

You have written a book on 3D imaging – it was published last year - so I was going to ask you, what drew you to book writing?

I fell into it slowly, one step at the time. It started by putting together a set of lecture notes that I wrote for my classes at Stanford. Then, as I had been warned, I found out that going from lecture notes to a book is much more work than it seems at first. The main goal was to make the document more than a teaching tool but something that could be helpful for the whole community as a reference - a tool for professionals out there to stay updated with important progress in seismic imaging as well as for young people entering the profession to learn the basic concepts and some of the more advanced methods. And then there is also a personal reward: writing a book helps you, or forces you, to clarify your own thinking. It forces you to be more precise and to scratch below the surface of your current understanding of the basic concepts and of the crucial details. Usually, new ideas spring out of this kind of effort.

What are your other interests, apart from the science that you practice or teach?

On the intellectual level I am actually quite interested in economics and political sciences. Whenever I want to distract myself I go and read in the fields of science, economics, or politics. At the personal level family is central to my life. I have two young kids, nine and seven, and spending time with them and my wife is clearly a priority. I enjoy practicing sports. Unfortunately with age and limited time the number of sports I practice are greatly reduced. I re g ularly go mountain biking in the hills behind Stanford and I go skiing in season. I like traveling and discovering different ways of living and thinking in new countries. The DISC is exciting for me in that respect. It is even better if I can travel with the family. We went to Japan together, and it is great to visit a country you have never been to before and discover it through more innocent eyes, or better, less biased eyes, the ones of your kids.

What would be your message to young entrants who have just taken up Geophysics as a profession?

Be ready for change. The profession has changed since I got here and is going to change even more in the future. So I feel that what is important is to spend your time and energy where you think that you are learning and don’t be too concerned about the immediate return on what you are doing; the payback will come, just be confident. Spend time enriching your skills and then you will be ready for whatever happens, because nobody can predict what is going to happen. Hopefully you will have a productive career that spans 30 – 40 years, and clearly in the next 30 – 40 years the industry and Geophysics will change dramatically. I feel that the skills you learn now will be very useful, both in terms of the more specific technical skills but even more the general problem-solving skills that use modern computational and mathematical methods to solve engineering and science problems.

One last question, did I miss out on any question that you expected me to ask and I didn’t cover?

No, you did a great job.

Well, Biondo thank you very much for giving us this opportunity to sit down and talk to you and get your views on some of these topics that we touched on. It has been a pleasure.

It was great talking both of you, I enjoyed it, and thanks for spending the time and hosting me.