If oil prices hold above $50 a barrel, the fledging comeback in U.S. drilling could crescendo into another oil boom over the next two years.

In a report Tuesday, the Energy Information Administration said it believes a second burst of shale drilling could bring U.S. oil production close to an all-time record by the end of 2018. That analysis, if correct, would mark a swift turnaround for an industry devastated by low oil prices in recent years, and challenge OPEC's efforts to rein in the global oil glut.

"OPEC knew the likelihood of U.S. shale picking up, but what they didn't know - and what none of us know - is how strong it will come back," said Neil Atkinson, head of the oil markets division of the International Energy Agency.

The EIA projected the nation's output could vault above 10 million barrels a day by the fourth quarter next year, an increase of 1.2 million from current levels. A surge of that size would put U.S. oil production within 30,000 barrels a day of the nation's record, set in November 1970.

One big reason the EIA expects output to climb is that companies are shelling out more money to pump oil. Forty-four U.S. oil producers hiked spending in the fourth quarter by a combined 72 percent, or nearly $5 billion, compared with the same period the year before.

Another reason is that shale drillers have likely already seen the worst of the sharp oil production declines that come with drilling wells into dense, stubborn shale rock.

Typically, shale oil production drops sharply after a well has been actively pumping for a year or two. But because U.S. drilling fell off dramatically in 2015 and 2016, the shale industry's oil production declines have largely played out.

"It's more stable now," said John Staub, director for the office of petroleum, natural gas and biofuels analysis at the EIA. "They're not fighting as hard against production declines, and they're ramping up with new wells."

The EIA believes that burst of oil could weigh on oil prices. It expects U.S. oil prices to average $52.24 a barrel this year. That figure is down 2.3 percent from the projection it made last month. On Tuesday, crude oil rose 32 cents to $53.40 a barrel in New York.

Around the world, oil production could rise to more than 100 million barrels a day by the end of next year, with most of that output coming from countries outside the Organization of the Petroleum Exporting Countries.

In the United States, the drilling surge has already begun. Last month, the number of new U.S. drilling permits issued by Texas, California, Oklahoma, Colorado and other states surged by nearly 4,000, the largest monthly increase in 18 months, according to data compiled by investment bank Evercore ISI.

"The U.S. is now a bigger actor in the world," said R.T. Dukes, an analyst at energy research firm Wood Mackenzie in Houston. "And these companies want to get back to growth."