Tracing the Industry

How I got involved in the seismic industry

So many people have such interesting pathways leading into and through the seismic industry. I am also pleased to share these stories with the RECORDER readers. If you would like to share your story, get in touch! This month I have the pleasure of sharing the story of one of the RECORDER’s Technical Editors, Rob Holt.

The ups and downs of the life of a geophysicist – Rob Holt

Much as a seismic trace is composed of a series of peaks and troughs, so is the life of a geophysicist.

My story begins in the southeast corner of England, in a mid-sized Saxon town called Guildford, which is located about half way between London and Brighton. Guildford is known for William the Conqueror’s ruined castle and its cobbled pedestrianized high street that slopes fairly steeply down to the River Wey. From the age of 11 to 18, I attended the all boys Royal Grammar School, which was established by King Edward VI in 1552. My headmaster told us to “work hard, play hard” during every assembly, and I have since adopted his motto as my own. It was quite an old-fashioned educational experience, so much so that I was the secretary of the school’s rifle club in the upper sixth, and we enjoyed touring the nearby public schools at weekends for various shooting competitions.

At 18, I left home to study physics at the University of Birmingham, where I played hard and worked just hard enough. This was a fun time for me as Birmingham, home of Iron Maiden, had some great rock clubs and an excellent music scene. During my third year, I took geophysics as an optional course, and it resonated with me. After finishing my degree, I took what is euphemistically called a “gap year” in the UK. At the time the economy was in recession, and jobs were few and far between. This, coupled with the fact that taking a pure science degree didn’t lead directly to a job, resulted in only a few interviews, and no offers. Notably, this was the last time someone ever said to me “you look too young” for a job. Eventually I sought the assistance of a career guidance councillor, and she gave me the best advice I’ve ever been given – “Do what you are good at and enjoy doing”.

Soon thereafter, I moved “up north” to take the Masters in Exploration Geophysics course at the University of Leeds. In those days, a master’s degree was crammed into one year. We spent the first 7 months or so in the classroom, from 8am to 5pm, plus evenings, studying and taking exams. Then we did our independent research project. I was lucky enough to do my project with Lasmo (now part of Eni), looking at seismic and velocity data from the South China Sea, offshore Vietnam.

A taste for travel made me apply for a geophysics Ph.D. at University College London, and the following spring I was on my way to Sabah, N.E. Borneo, to complete the gravity coverage of the region. My Ph.D. supervisor, Dr. John Milsom, and I were accompanied by a member of the Geological Survey of Malaysia and a driver, as we toured around Sabah – across the mountains of the Crocker Range and through the virgin rain forest. When we were close to the coast, we stayed in the nearest town, otherwise we stayed anywhere we could – options, electricity and restaurants were usually very limited. I’ll never forget being followed around the small villages by the local kids who had never seen “orang puteh” before. Back at the university I merged the new gravity data set with the existing onshore data and newly-released offshore satellite data. Interpretation followed, and I spent the last 8 months of my time in London frantically writing my thesis. By this time I had perfected the “work hard” part of my old headmaster’s motto, and I managed to finish my PhD 38 months after starting it, just as my money ran out.

I was on a plane to Houston literally the day after I submitted my bound thesis for examination. The job market had finally picked up, and a few months earlier I had successfully applied for a seismic processing job with Veritas in Houston. It was time for me to leave academia, and I did so with one suitcase, a very old wardrobe and an empty bank account. I started work on a Friday and proudly walked into the office wearing my new suit and tie, only to be told that I was over-dressed as it was casual Friday. The following Monday I wore the same suit and tie to work and was told that “only managers dress that smartly”. By Tuesday, I had it figured out.

With a Ph.D. behind me, I was thrown in at the deep end. My first project was the processing centre’s first 3D post-stack depth migration of a smallish 3D from southern Texas, and this was immediately followed by a pre-stack depth migration of the same survey. I almost sunk. With no background in the software, and minimal help, I worked night and day to squeeze out the best result I possibly could. I’d rate it a B- performance today. It was only after I moved to the Gulf of Mexico marine spec processing team, and was introduced to the art of writing C-shell scripts to efficiently submit, monitor and QC the hundreds to thousands of processing jobs that made up a seismic processing project at the time, that I began to flourish. A couple of promotions followed fairly rapidly. There were a lot of good people in the Veritas processing team, we hung out together after work, and life was great.

By the year 2000, the time had come for me to make a decision – whether to settle down permanently in Houston, or to move somewhere else. Pat McKenny let me know of a three month temporary position helping Veritas’ Calgary office expand its marine processing team, and before you knew it I was there (here). Three years later, I was still in Calgary, married to my beautiful Canadian wife and busy working on a family. A pickup truck had replaced the red convertible Ford Mustang GT I drove up from Houston. By that time, it was clear to me that our industry has a strong onshore focus, and I was lucky enough to be able to engineer a move within Veritas to Rob Vestrum and Jon Gittins’ land anisotropic depth imaging group. I had quite a shock the day my first client told me, fairly gently, that he couldn’t see his exploration target on my PSDM stack. I had done such a thorough cleaning job on his seismic after migration to make it look like the marine seismic data that I was familiar with, that I had destroyed his beach barrier bars. Luckily they were easily restored. Lesson learnt – always know what the goal of the processing is when you start a new project, and QC horizon slices at the target level at different stages in the processing workflow!

In 2005, I moved to WesternGeco to replace John Mathewson and run their depth imaging team. Working with great clients like Sylvestre Charles of Talisman (at the time) and Husky enabled me to grow my depth imaging team from 3 to 9 people over the following three years, and work on some really cool imaging projects – foothills depth imaging, reef hunting, and large marine projects. In one project, we were able to dial in the anisotropy parameters by adjusting them until the fault plane reflections lined up with the reflector terminations. Depth errors in this project were remarkably low, despite only having one depth calibration well.

Itchy feet, perhaps, and a new opportunity saw me move to Shell in 2008, just before the gas price crash. I swear the recruitment door slammed shut just behind me. First, I worked in the imaging team, running a couple of production imaging projects to learn the software. Every senior Shell processor has to work on the Waterton PSDM project, and I had fun adding anisotropy to the model and playing with the frequencies in the data. Then I moved to the Technical Services team to extract azimuthal signals from 3D seismic data, and to try to relate these signals to the properties of the natural fracture network. Back in the day, this was the flavour of the month. About this time, I started teaching “geophysics for unconventionals” within Shell. It wasn’t long before I started my second, related, research project, the goal being to improve the quality of the seismic data so we could extract higher quality azimuthal attributes. Whilst I don’t believe we can reliably predict the properties of natural fracture networks from the azimuthal variations observed in our seismic data, I was able to quite dramatically improve the pre-stack and post-stack imaging of low reflectivity intervals, such as the Montney, using some novel processing workflows that I had developed. This had spin-off benefits, such as imaging some of the more subtle faults for drilling hazard studies.

I moved to my final position at Shell, subject matter expert and senior seismologist in the Technology Excellence and Deployment (TED) team, in 2013. This was a broadening assignment – quite how much of a broadening assignment it was wasn’t clear to me until November 5th of last year. Despite this, working in the TED team was an excellent experience. It’s not often you get to run your own research project surrounded by technical experts from so many other disciplines including petrophysics, geology, geomechanics and engineering. With hindsight, it’s too bad that economists were not also on the team. I built a brand new quantitative reservoir characterization workflow for unconventional plays, adapted from some externally published papers, that enabled us to predict mineral fractions from elastic rock properties at the well log and seismic scale (see my paper with Bill Westwood, in the February 2016 CSEG RECORDER, page 22-26). We can use these mineral predictions to estimate petrophysical and geomechanical properties, microseismic behaviour and completion pressures.

Currently I am seeking my next position – check out my resume at www.linkedin.com/in/raholt. Through my career to date, I have been quite lucky and have experienced far more ups than downs. Thanks Carmen for asking me to write this article. Also, many thanks to the multitude of highly talented industry professionals I have had the pleasure of working with up to now. My career path has been shaped by many excellent mentors, and credit for the success that I have had is shared with the people I was working with at the time.