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My geophysical toolbox, circa 1973

I pulled up in front of the old Esso building in Calgary, adjusted my tie, gulped, and walked in. After a bit of an orientation, I was introduced to my first boss. My training assignment would be the Canadian Arctic, where Esso was actively drilling onshore and offshore. Eager to make an impression as a worldly wise professional, I asked, ‘Will I get to work on Prudhoe Bay?’ My new boss exhaled, leaned back, and said, ‘No. That’s in Alaska.’

There was only one way to go from that auspicious start, and that was up.

New graduates will find 1973 technology hard to imagine. No cell phones, no computers, crude calculators. Seismic interpretation was done on big rolls of paper on long tables using coloured pencils and a large box of erasers. We each had a big draftsman’s brush to remove eraser debris. Interpreters had stiff necks from leaning over the table to look sideways at the section: it was the only way to change the horizontal scale.

We had to be creative. I remember one geophysicist using a razor blade to cut his section into individual traces, then gluing it back together flattened on a reflector. Don’t laugh! That method found a new Zama Reef pool in northern Alberta. 

There’s more than one way to flatten a section though, and there were some very innovative individuals at Esso in this analog age. One built a special camera for flattening. It was crude but effective: a geophysicist hand-picked a reflector on a film, which was run slowly through a large camera on a movable platform. The operator tracked the horizon, using a mechanical lever to keep it centered in the view-finder. Voilà — a flattened section!

Filtering was a special challenge. Ernie Shaw and Jack Hogg devised a laser imaging system that split the reflection of a seismic image through a fluid with a precise refractive index. It was then fed through a crude filter cut from a sheet of tin, which blanked out some of the spectral components, then back through a reversal of the set-up. The result: the first analog f-k filtered sections. 

Once complete, interpretation times were carefully measured with a pair of dividers, then painstakingly transferred from paper sections to basemaps, one shotpoint at a time. Often, even the basemaps had to be hand-drawn, and a single map could take weeks to produce. Of course, all contouring was done by hand. Once a map was deemed final, it was sent to the drafting department to be reproduced.

I was told that I was lucky to be living in modern times — we had 24-channel systems shooting up to six fold! In the old days, the veterans reminisced, a geophysicist accompanied the acquisition crew and made maps from picking shot records. This seems crazy, but most of the oil in Alberta was found that way.

Despite everything, my first well was a giant discovery, Issugnak. A great way to start! Except that it’s still sitting there with a net present value of zero, and that won’t change until the Mackenzie Valley pipeline is built. It transpired that Wes Hatlelid had mapped it a few years before me, but Esso had lost it! We spent two years searching for the field before we discovered it again, right where we’d left it.

How did this happen? Remember, this was way before GPS; we barely had satellites. Near-shore surveying was done by triangulation from shore-based transponders. I have painful memories of hauling 12-volt batteries on my back up to those stations, all located on the highest hills we could find. It turned out that one of the transponders was giving spurious readings, so the survey for that summer’s shooting was wrong. Take nothing for granted when you look at old data.

Biostratigraphy at a distance

Biostratigraphy at a distance