The statistics, released by the U.S. Geological Survey on Tuesday, were eye-popping: 20 billion barrels of oil, just sitting there, trapped in a layer cake of rock under a vast swath of West Texas.

That’s almost three times the amount of recoverable oil that the agency said there is in the Bakken-Three Forks formations, which have been the center of North Dakota’s recent energy boom. As of Wednesday, that amount of oil would’ve been worth roughly $900 billion.

The West Texas formation, known as the Wolfcamp shale, is also the biggest continuous oil accumulation ever assessed in the country, the USGS says.

But experts say the news is less a eureka moment than it is confirmation of what many have long guessed.

“It’s not a new discovery,” said Michael Plante, a senior economist with the Federal Reserve Bank of Dallas who focuses on energy. “The estimate is just a reflection of what a lot of the companies [drilling] out there already suspected.”

Still, the findings point to what experts say is a shifting reality for American energy producers -- one in which deeply ingrained worries about a dwindling oil supply have become almost moot.

“We will never run out of oil,” said Bernard Weinstein, associate director of the Maguire Energy Institute at Southern Methodist University.

The Wolfcamp shale formation is in the Midland area of the Permian Basin, which is the most prolific oil and gas field in the continental U.S., Weinstein said.

The Permian Basin was first developed in the 1920s, when the only way to access oil there was through what’s now described as “conventional” vertical drilling.

With the advent of horizontal drilling and hydraulic fracturing, though, oil that’s distributed throughout shale rock is technically possible to extract.

That evolution in technology, as well as improved technology for extrapolating how much recoverable oil is in a given area, has prompted the USGS to take second looks at oil fields around the United States and offshore.

“It just so happens that the Wolfcamp is what we just finished,” said Chris Schenk, who heads oil and gas assessment for the agency. “We do prioritize the bigger areas, but we are responsible for the larger U.S.”

Source: U.S. Geological Survey (Laurie Joseph / Staff Artist)

Next up, he said, is the Delaware Basin, which is also part of the Permian.

Schenk said it’s tough to say how the Wolfcamp shale numbers will stack up against other formations, as the agency revisits other basins -- though it’s hardly a secret that there’s oil to be had there.

Right now, Schenk said, there are about 3,000 wells drilled into the Wolfcamp shale.

The Permian Basin, including the Wolfcamp shale, has been a singularly powerful magnet for oil producers since well before the USGS released its assessment.

A U.S. Energy Information Administration report also released Tuesday showed that the Permian dominates the country’s oil drilling activity. Its number of weekly active drilling rigs has in recent months almost reached the number in the rest of the U.S.

Energy companies are scrambling to buy up acreage in the area, spending billions to purchase land assets.

And its oil production has climbed since 2007 -- hitting just over 2 million barrels a day this year -- even as other oil-producing regions such as South Texas’ Eagle Ford and the Bakken have dropped off following the oil price plunge.

Todd Staples, president of the Texas Oil & Gas Association, said in a statement that the trade group saw “massive opportunity” in the Wolfcamp formation and the Permian.

“Texas is already the No. 1 oil and natural gas producer in America and the staggering potential of the Permian Basin will cement that spot at the top, strengthening our economy, our environment and our future,” he said.

Plante, of the Dallas Fed, cautioned that energy is an industry full of ups and downs, and drilling that’s profitable today may not be tomorrow.

“Oil has been a weight on the Texas economy itself, but the Permian seems to have turned a corner,” he said. “In some regards people know it’s boom-bust, but in other regards, I’m not sure there is a way to deal with it.”

Plante said he didn’t anticipate Tuesday’s announcement would affect oil prices much -- only “insofar as it’s new information.”

Weinstein said that the USGS’ assessments in recent years have consistently turned up oil and natural gas estimates that are much higher than previously thought.

“Last time they revised offshore estimates it was like a 200 percent increase,” he said. “There are huge reserves in the Gulf of Mexico ... on federal lands -- there’s stuff everywhere.”

That means that, even if the oil stays far below ground, the U.S. is in a much different position when it comes to energy than it has been in past decades.

“Long term, it clearly enhances America’s energy security, knowing we have that much more we can tap,” Weinstein said. “It does give us a lot more leverage in the geopolitical arena, if we’re the No. 1 oil and gas producing country in the world.”

But that doesn’t necessarily mean we’re in for a return to an exclusively fossil fuel-powered nation. It just underscores the weight of policy decisions.

For instance, Weinstein said he didn't expect federal subsidies for alternative energy sources to dry up, even under a Trump administration that has leaned into claims that human-caused climate change is a hoax.

Ending existing tax credit programs for wind or solar energy is “easy to say, but politically harder to do,” he said, because, “Where are the wind farms? Red states: Iowa, Kansas, Nebraska.”