Changing cultures to attract millennials will be key to oil and gas employment strategy.

Millennials make up the biggest age grouping in American history, at 80 million. That means that whether the world is ready for the personality traits associated with them, millennials are about to comprise the majority of the workforce.

In the oil and gas industry, that change is going to happen sooner rather than later, a phenomenon many in the business call "The Great Crew Change."

After the oil bust in the 1980s, millions of jobs were cut from the industry. Few college students were entering energy-related fields and the number of new hires stagnated. Had they been hired, those people would now be in leadership positions. Instead, the age range for oil and gas employees is a U-shaped curve. There are many oil and gas employees near retirement age – and many millennials.

"Half the workforce is going to retire within a decade," said Sarah Sandberg, chief operating officer at the Colorado Oil and Gas Association, in an interview with local news outlet the Greeley Tribune. "So there's a really fast approaching challenge of transferring knowledge to millennials … and that gap between the old and new workers needs to be filled in as quickly and effectively and efficiently as possible."

Sandberg said to do that requires a proactive approach now, rather than once the retirements begin. The way to do that is to embrace millennials, she said, and to look at the generation's traits as opportunities rather than challenges.

Millennials look for more flexible work environments and better benefits packages. These things require companies to make culture shifts and find the funds to do it, but they're things that benefit all employees, she said.

And since Millennials are known for a desire for instant gratification, Sandberg said the opportunity to solve problems — and solve them fast — is huge.

Sandberg said there's a lot of environmentally-conscious efforts, research-driven development and a culture of innovation in the oil and gas industry now that does align with millennials' desire to do right by the planet.

Another opportunity for the industry is to increase and foster a culture of diversity. While millennials are the largest generation to date, they're also the most diverse, according to the American Petroleum Institute.

Energy information analysis company IHS projects that through 2035, nearly 1.9 million jobs will be available in oil and natural gas, and nearly 1 million of those will be filled by African-American, Hispanic or female employees.

The biggest obstacle to diversity in the oil and gas workforce as it currently stands is opportunity for STEM, or science, technology, engineering and mathematics, education opportunities to women and minorities. Rebecca Winkel, economic policy adviser at the API, said the biggest thing the oil and gas industry can do is to ensure equal opportunities to education.

"We want to attract and retain the best available talent, and that means encouraging more women and more minorities to pursue STEM fields," she said.