“I still enjoy the physics aspects of geophysics the most…”

An interview with Steve Jensen

Coordinated by: Satinder Chopra | Photos courtesy: Vince Law
Steve Jensen

Steve Jensen is the senior-most geophysicist with Nexen Petroleum International Ltd. and has spent more than three decades in this profession, experiencing the changing winds of boom times and bust times. His long pursuit of exploration activities both domestic and international have enabled him to understand the interplay between exploration strategies and the tools of exploration. When approached for this interview, he agreed enthusiastically. Satinder Chopra and Jason Noble had a very interesting and engaging discussion with Steve.

[Satinder]: Steve, tell us about your educational background and work experience?

I began as a physicist. I got a Bachelor’s degree at University of Denver and then I went to University of Wyoming for my Ph.D. work. At that time my intention was to be a solid state physicist. But it turned out that I was among the first big group of physicists graduating after the Russian satellite successes. There was quite a flood of us and we got our degrees during a recession. That was the time when physicists were driving cabs. I decided I should find something more in demand than solid state physics, so I went into the geophysics program at Wyoming. I did my thesis work in rock magnetism, which was fairly new and trendy at the time, and I got my degree in 1972. I spent two years as a Killam Fellow at Dalhousie University doing more rock magnetism. Still there were no jobs. I was actually considering applying for retraining as a welder. But after 75 letters of rejection, I received a job offer fro m Shell in 1974. I worked for Shell for 10 years in a variety of endeavours: marine and land processing, data acquisition, and interpretation in the Deep Basin and on Mannville plays. I spent a fair amount of time in the special projects group working for Tai Ng. I remember working on Shell Canada’s first colour amplitude display program for seismic, which involved overlaying very expensive colour films on a wiggle display. I also spent 4 years as uranium geophysicist in the minerals department, with Mel Best as the geophysics manager.

In 1984 I moved to Canadian Occidental, which at the time was small but rapidly growing. The merger with Cities Service had just taken place. They were still merging staff and activities when I joined. I started as supervisor of their southern geophysics group, which had southern Alberta and parts of Saskatchewan. Barb McClary had the northern group, and Hank Geerlof was our geophysics manager. We had inherited a huge land base from Cities, so we were very active for some years, doing quick evaluations of these properties before they expired. My areas of responsibility included the southeast Saskatchewan Mississippian edge plays, Jurassic prospects in the Grand Forks area, the Carrot Creek Cardium play, Mannville prospects in eastern Alberta, and some foothills acreage.

Steve Jensen
Satinder Chopra and Jason Noble in conversation with Steve Jensen.

In approximately 1987, we got into the international arena in a big way in Yemen. We were essentially told to go into Yemen by our then parent company, Occidental. South Yemen at the time was a Russian satellite, and Oxy, as an American company, was not welcome. They wanted to pick up a block there. We were sent as Oxy’s strong left wing, so to speak, picked up a block, and had a major success. Simultaneously with this, the company shut down Canadian activities for a time, as there was not enough money to fund both programs. I switched to international and became Chief Geophysicist in 1991, reporting to Keith Peterson. In this job I had quite a variety of experiences in a lot of different locations. One particular project comes to mind: we did a gravity survey in Kalimantan (Indonesian Borneo) using the then-new GPS system, without any cut line. We relied on paths connecting the hill rice farms that covered the area. When the meter readers got within 100m or so of a nominal station, as determined by GPS, they called it good and took a reading. We did the survey for a fraction of the initial quoted cost.

In 1994 I requested a transfer back to project work and was assigned to offshore Vietnam, where I shot and interpreted 2D and 3D programs. We drilled a couple of non-commercial gas discoveries on the block. I was then transferred to the Australia group, where I was team leader for nearly 5 years, working on the Northwest Shelf, including our Buffalo field. Now I am in the new ventures group, having just finished work on a 3D survey in one of our Yemen blocks.

[Satinder]: So you had a different ambition while growing up but switched to geophysics for obvious reasons?

That’s correct. Of course geophysics was not really a separate field of study when I was a kid. There were few independent geophysics programs or departments. I enjoyed the physics. I switched to geophysics for employment opportunities and because of my academic interest in rock magnetism and sea floor spreading, and got into seismic exploration after that.

[Satinder]: So you became a marine processor?

I did. I helped process Shell’s data in Hudson’s Bay and then some of their early offshore lines in Newfoundland.

[Satinder]: Did you find it challenging, coming from physics and doing marine seismic data processing?

It was quite a bit of a change and I had quite a bit to learn at the time. Of course processing was a simpler thing in those days; but yes, it was a challenge.

[Satinder]: Could you tell us about some projects that really fascinated you?

Well, Shell was shooting in Hudson’s Bay, which as you know is a multiple- prone area with shallow water. They had invented a super-long airgun array, which succeeded in attenuating the multiples. I was involved in processing that data. They had made a quantum leap in data quality over previous vintages.

[Satinder]: What was the uranium geophysics about?

Shell had a minerals department. Most oil companies did at that time. Its mandate was principally hard rock exploration for base metals; there was a separate coal subsidiary. The market price for uranium was quite good, and Shell decided this was something they would like to pursue. I was responsible for pretty much all aspects of uranium geophysics, including rental of equipment and contracting of services; I did a great deal of actual surveying myself in the north, most of it EM and potential field. Shell gave us a cheque book and put us on a plane with some equipment; when we had our maps made, we came back.

[Satinder]: It must have been challenging in that adequate care has to be taken to deal with radioactive materials.

That’s true, but it is seldom that this affects the geophysicist. You do not often find dangerously rich samples on the surface, although some of the underground deposits in northern Saskatchewan are in fact too rich to mine safely. We did, however, occasionally pick up enough traces of pitchblende to interest others. We once did a field trip to the Pickering nuclear power plant in Ontario and triggered their security. Geologists were going through the screening area with their field packs, and there was enough pitch on them to be picked up.

[Jason]: It seems you’ve had an incredibly varied career. What did you find the most interesting?

I still enjoy the physics aspects of geophysics the most. I am fascinated by the recent developments in pre-stack inversion and the use of attributes to characterize reservoirs. But there is a tendency to farm out that kind of work to speciality companies, since it is hard for an interpreter to stay current with advances. Geophysics has become a very big field.

[Satinder]: I would like to get your comments on heavy oil exploration in Alberta. Tell us about its interpretation on seismic data?

My own work was in exploration. It was a matter of identifying channel sands and traps, looking for differential compaction and, sometimes, associated gas, almost always on 2D data. We spent a lot of effort trying to increase bandwidth. Today, there is a lot of development work. I think that Canadian companies are the state-of-the-art where 4D seismic and reservoir characterization in enhanced recovery projects are concerned. Certainly, Nexen is putting a lot of effort into this sort of thing.

[Satinder]: Why did you quit Shell to join CanOxy, now Nexen?

Shell at the time was a great place to begin a career, since the training for a new geophysicist was superb. But for such a big company, there was a great deal of the Canadian patch that was not of economic interest. Just before I left, the chief geophysicist of the day had called the explorationists to a meeting and indicated that Shell had not found anything of material interest in the plains for some years; they had decided to phase out the plains operations. But they had conducted a review and had concluded that money was still to be made in the plains; they were going to give it a few more years. I took it as an advance warning that there probably would be a lean future there for plains geophysicists. And so it turned out.

Steve Jensen

[Satinder]: What differences in work culture did you notice between the two companies?

CanOxy at the time was still a small company. They were less specialized internally and more active; the effort was to drill up the land base before it expired. There was great pressure to get locations quickly and to get them drilled, whereas at Shell it was a slow process to get wells approved. So, this was a much faster-paced company than Shell was.

[Satinder]: I think now you are at a similar juncture at Nexen, as it was at Shell, where the domestic is not such a growth area or a high profit area and you focus more on international?

That is true, although we are placing large fraction of our capital into heavy oil and tar sands projects. I would say it is probably true that conventional oil in Canada is being de-emphasized. But in terms of capital expenditure, Canada is right up there .

[Satinder]: Apart from heavy oil in Canada, what are other areas where Nexen has been active?

We have had success in the Gulf of Mexico. Of course, we have done well in extending our Yemen fields. We have had production at various times in the North Sea, Ecuador, and Australia; and we are active producers and explorers in Colombia and Nigeria. We have not yet found a second Yemen, but a discovery like that does not come along every day.

[Jason]: How has that gone, as a relatively small Canadian company competing with majors and super majors?

I think fairly well. Of course we don’t have the data base that they have or the regional mapping. But we focus on areas we think are of interest and try to build expertise.

[Jason]: Has your experience in Yemen helped in that respect?

Yes and no. It has provided much of our income, and it allowed us to gain experience in international operations and in dealing with foreign governments. Also, it provided us with an exploration model, as a virgin area which we knew from regional geology had grabens and, probably, source rock. On the other hand, it has led to the desire to repeat the big hit. We wanted to find another billion barrel field, and the effort to do so has at times led us into risky plays. So it has worked both ways.

[Satinder]: When you look back on your geophysical career, what were some of the successful landmarks?

My experience in minerals was a very definite landmark. Mining geophysics is very interesting, because there is a wide suite of tools and techniques, not just seismic; and we got a chance to do it all ourselves. I thought it was a very broadening experience; the first wrench fault and flower structure I ever interpreted was on a refraction survey acquired for Shell Minerals. That was definitely an experience! Another success, at Shell, was mapping a Leduc pinnacle near Simonette on noisy old 6-fold trade data; Shell eventually drilled it. And I very much enjoyed working on Australian projects. In the end, most of our prospects did not match the company’s portfolio criteria. But we did a lot of good work and had a lot of fun. We made a net profit in Australia, and our Buffalo field is still producing.

[Satinder]: Who were some of your mentors?

One of the first was Mel Best. He was my boss at Shell Minerals and subsequently went to the GSC as director of research in Bedford and, later, in Victoria. Also Tai Ng, who was my supervisor in Special Projects at Shell and who later went on to a distinguished career at Canadian Hunter.

[Satinder]: What one quality would you attribute your professional success to?

Flexibility. I remember a retirement party for Doug Sheier, the exploration vice president at CanOxy, just as we were shifting our effort to Yemen. We asked him for his advice; he said, “Adapt or perish.” That is certainly the name of the game.

[Satinder]: You have been in the industry for more than 3 decades. Tell us about how you saw the technological changes shaping our seismic industry?

The most significant change was computerization in interpretation; anyone would say that. It would be impossible to do the things we now do, like AVO analysis, seismic attributes, or interpretation of large 3D’s, on paper sections. Another thing is the tremendous improvement in seismic processing. It is amazing what can be done to bring signal out of noise. Of course, I am thinking of advances over several decades, but the improvements haven’t reached a plateau yet. The nearly universal use of 3D has been a great change.

One other major advance, more important in international work than in western Canada, is the use of sequence (and seismic) stratigraphy. It provides a paradigm of how to begin interpretation in an area where data is sparse.

[Satinder]: What do you think is the trick for surviving in this industry?

It seems to me that if you are going to work for an oil company as a geophysicist, rather than for a contractor, you have to have a broad knowledge of pretty well all parts of the business. That includes drilling, economics, risk, geochemistry, and reservoir engineering, as well as geophysics and geology. Then you ought to have some sort of technical specialty and be in touch with contractors working in that specialty. We all like to do high-tech work, but the reality of staffing and deadlines means that often this kind of work must be contracted out to consulting firms. When I joined the industry, big companies did everything in-house. Acquisition and processing were the first specialties that were contracted out. Now bits and pieces of the interpretation process are being sent out.

Steve Jensen

[Satinder]: I am wondering if you could say a few words about what you are doing now and where your career is going?

Currently, I am in the new ventures group, and will probably be there for some time. I have fairly broad experience, which is useful in new ventures. And I am reasonably familiar with our different areas of interest. But I don’t want to do that for ever; in new ventures, one mostly flies around the world and looks at other people’s work. Too much of that makes a geophysicist obsolete; it’s important to do hands-on work. I’ll stay with it as long as it is interesting. I still have another decade to go.

[Jason]: You still look forward to coming to work every morning?

Most days.

[Satinder]: Tell us where Nexen is engaged in exploration within and outside Canada?

Within Canada, we are largely focused on the North; but most of the capital, as I have mentioned, is going into the Long Lake tar sands/ heavy oil project. We are active in the US Gulf Coast, including deepwater plays, where we have had significant success. We are still very interested in Yemen, and are actively exploring our blocks there. We have a block in Equatorial Guinea, three blocks in Nigeria, and producing properties in Colombia.

[Satinder]: How about the North Sea?

We currently aren’t doing much in the North Sea. We had a number of blocks in the past, with production. These were sold; the company felt there were better growth opportunities elsewhere. Currently, we have no property in the North Sea.

[Satinder]: Could you tell us about some of the new technology ideas you have been adopting in your interpretation of seismic data.

Not necessarily new, but increasingly important, is seismic stratigraphy. Especially in areas where there is little well control, it is the essential initial approach in interpretation. I have, over the last six to eight years, spent a fair amount of effort trying to become proficient at it. We follow in large measure the techniques and approaches of Ward Abbott, who was the chief stratigrapher at Occidental for years and who has been our mentor in this field. As well, we have John Wagner in our Dallas office, who is a noted authority in the field; he has conducted courses and field trips for us. Another promising technology is the use of pre-stack inversion for lithology prediction. I have had some success with it, but it is difficult to use where there is sparse well control. I use Coherence Cube data for fault interpretation on 3D data.

[Satinder]: Do you like to volunteer your services to a professional society like the CSEG?

I haven’t done much along that line. In terms of professional service work, I have had summer students from time to time.

[Satinder]: Would you like to do volunteer work given a chance?

Yes, I might like to do that.

[Jason]: Be careful, that is a loaded question!

That’s why I qualified my answer!

[Satinder]: Tell us about some of your recreational activities?

I am very fond of outdoor activities like backpacking, hunting, and back country skiing. As for indoor pursuits, I am an avid reader and enjoy classical music.

[Satinder]: Just to finish up, what would you say as a message to our young members, who have just taken geophysics as a profession?

I would say to look around widely in search of a career. Possible career paths are more varied than they were 30 years ago. I think it is desirable to have processed for a time, which is training that new interpreters don’t get much of any more; and there is usually a good market for career processors. Although I think there will be conventional exploration in Canada for quite some time, I’d say the growth field in Canada is development geophysics. The long term future for exploration geophysics will increasingly mean international work. I would also encourage young geophysics graduates to consider minerals geophysics, and also environmental geophysics, most especially related to g round water. It is not often realized how rapidly water resources are becoming critically short, and I think geophysics has a role in dealing with that problem.

[Satinder]: Thank you very much for giving us this opportunity to come and talk.

I hope it’s been of some interest.


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