Elizabeth Oko smiling
Oko has spent more than four years studying the Vito oil field

For Elizabeth Oko it felt like it could be a defining moment in her career. It was the summer of 2017, and her team of geoscientists was predicting a large discovery of oil at the Vito field in the US Gulf of Mexico.

Given the cost of developing deep-water oil and gas projects, they knew they couldn’t afford a mistake.

In the past, during moments like these, it had been helpful to lean on her most senior colleagues, people like Brad Robison and Fred Diegel, two skilled geologists who had mentored her and were now comfortably retired.

The knowledge gained from decades of exploration that Robison and Diegel possessed could be vital in assessing whether the Vito oil field was worth the investment.

“When they retire, geologists and geophysicists go out at the top of their technical calibre,”  says Oko. “In our world, the more you’ve seen, the more you’ve been surprised – both good and bad – the more knowledge you have to apply when you interpret data on the next project.”

She decided to take a leap, and emailed the two men to invite them to join her team. “Remember me?” she asked in the subject line. They did. And they accepted her invitation.

Global skills gap

Shell is not alone in appealing to the older generation to return to the workplace, bringing their experience with them. Workforce analysts are reporting a global skills gap exacerbated in large part by the retirement of the baby boomer generation, born between the late 1940s and early 1960s. This expertise is not easily replaced.

So recruiters are advising companies to stay connected with their retirees through alumni networks and non-profit organisations, like AARP, which serves Americans age 50 and older, so that they are within reach for temporary work or consulting.

“Employers call us and say, ‘We’re looking for older workers, so can you help us find them?’” says Susan Weinstock, vice president of financial resilience for AARP. “At a time when we have labour shortages, your older workers can be a company’s best assets.”

Oko and her team had spent four years studying the Vito oil field to understand the size of the discovery, using advanced seismic imaging and calling on years of collective experience and rigorous training. They also had access to numerous experts within Shell.

But salt layers deep in the seabed of the Gulf of Mexico, created millions of years ago by the evaporation of sea water, were muffling the seismic signals sent back by ocean-floor sensors, and complicating the task.

It was when Oko grew concerned that the seismic processing might be unreliable that she thought back to a time when seismic data was less precise – and the expertise of the geologist was all-the-more critical to the decision on whether to drill, or not.

“This is the kind of thing that happened a lot in Brad and Fred’s time,” says Oko. “You had to rely more on geology – and geologists.” The old-school approach required a closer study of the rock layers beneath the ocean’s surface and whether they were likely to contain a large reservoir or a small one.

Deep-water data

Robison joined Shell in 1979 and Diegel in 1985. They saw the beginning of the deep-water industry Shell pioneered. As decade followed decade, the drilling went ever deeper and production techniques became ever-more advanced. When they retired – Diegel in 2016 and Robison in 2010, that experience went with them.

Then Oko’s emails arrived. In August 2017, Diegel and Robison flew to Houston to study the Vito team’s data and talk to them about how they arrived at their findings.

After three days, they were able to confirm what the Vito team believed they had found. If anything, they said, the Vito team’s estimates were slightly conservative.

These findings were an important verification to Oko and the project team, clearing an easier path for the project to move forward. Vito, which Shell is operating in a joint venture with Equinor, was given the go-ahead for funding in April and is currently scheduled to begin production in 2021.

“Elizabeth appreciated that our experience had some value, that we had seen a lot of stuff,” says Diegel. “We asked a lot of questions, and I think it gave them confidence to see they had the answers.”

There’s no knowing when Diegel and Robison might be called upon again. The wheels of the oil industry turn slowly.

But both retired geologists enjoyed their involvement in a project of the future. They also enjoyed seeing how the young workers they mentored years before had developed. “A lot of the people who were brand new when I left the company were now in charge of things,” laughs Robison.

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