Falling oil prices could speed the departure of onshore drilling rigs from the state, particularly in the still-developing Tuscaloosa Marine Shale, which underlies parts of southeast Louisiana.

But experts say it will take a longer downturn to slow deepwater activity in the Gulf of Mexico, where the rig count is expected to jump 50 percent by 2016.

“Basically, lower prices will hurt all plays, but the Tuscaloosa Marine Shale, being so expensive, will be impacted the most,” said Kirk Barrell, chief executive officer of Amelia Resources LLC and author of the Tuscaloosa Trend blog. “It’s unfortunate timing because we continue to see excellent results.”

In the past month, the U.S. benchmark price of crude has fallen about 20 percent and stood Friday at $82.75 per barrel.

A price sustained that low will delay development of what economist Loren Scott described as the country’s “most vulnerable” shale formation. That’s because the break-even oil price for drilling a well in Louisiana’s piece of the Tuscaloosa is estimated at $92 a barrel, Scott said. In other shale formations around the country and in the deep waters of the Gulf of Mexico, the break-even point is more like $50, making those areas more attractive to oil and gas companies.

There were 19 rigs drilling for oil onshore in Louisiana last week, according to Baker Hughes. A year ago, there were 26. That compares to 209 rigs in the Eagle Ford Shale in Texas and 181 in the Bakken Shale in North Dakota, where companies can make money on oil priced as low $49 and $50, respectively.

Because of falling oil prices, two of the biggest players in the Tuscaloosa Marine Shale —Goodrich Petroleum Corp. and Halcon Resources Corp. — have seen their stock prices plunge nearly 40 percent. Encana Corp., a company with less exposure in the Tuscaloosa Marine Shale, is down 17 percent.

Both Goodrich and Encana believe they can reduce the break-even cost in the TMS to around $50 a barrel, although Encana says that will require reaching full commercial development. The company is still working out the formula to consistently drill high-producing wells.

Development in the Tuscaloosa Marine Shale — which stretches through the midsection of Louisiana into Mississippi — is still young. Oil companies have worked methodically in recent years to adapt to some of the formation’s geological complexities not found elsewhere.

Goodrich is the most active driller there with three rigs.

Since there’s so little drilling in the Tuscaloosa Marine Shale, lagging exploration won’t affect the Baton Rouge-area economy in the short term, Scott, the economist, said.

But the price drop will push back the anticipated economic boom from the Tuscaloosa, thought to hold 9 billion barrels of oil that could mean potentially thousands of high-paying jobs.

“You’re talking about billions of barrels of reserves. If it really started blowing and going, it would probably make the Haynesville Shale look like child’s play,” said Gifford Briggs, vice president of the Louisiana Oil and Gas Association.

In 2009, the Haynesville — a natural gas formation in northwest Louisiana — generated close to 57,000 jobs, and drilling companies dumped $10.6 billion into north Louisiana’s economy.

Briggs said the Tuscaloosa’s impact could be comparable to that of the Bakken in North Dakota or the Eagle Ford in Texas.

In 2013, the Eagle Ford had an economic impact of $87 billion and supported 155,000 jobs, according to the University of Texas at San Antonio.

“You’re talking about an incredible amount of investment, incredible amount of severance tax generation for local communities, royalties,” Briggs said.

For now, the deepwater Gulf remains far more important to Louisiana’s economy.

The firms drilling there think long term, seven to 10 years out, Scott said. The production from those wells is so great that if oil falls to $80 or even $70 a barrel, it’s not a problem.

Still, Nicolette Nye, spokeswoman for the National Ocean Industries Association, said lower prices may mean less money will be available for exploration, with fewer leases purchased and wells drilled.

“There will be efforts to economize and decrease costs associated with each barrel of oil. But the industry has seen the cyclic oil price pogo stick before, so don’t expect activity to grind to a halt,” Nye said.

David Welch, CEO of Lafayette-based Stone Energy, said deepwater Gulf projects have a break-even price around $50, so lower prices won’t force his firm to curtail drilling as much as companies in higher-cost shale formations.

Stone Energy, like most energy companies, has taken steps to protect itself from volatile prices.

The big questions are how far the price of oil will fall and how long the downturn will last, he said. Over the past 20 or 30 years, downturns have lasted anywhere from one to eight years.

In the past few months, both the U.S. and international benchmark prices have fallen close to 25 percent. Kuwait Oil Minister Ali al-Omair has said the international oil benchmark, which trades at a higher price than U.S. crude, may stabilize at $76 to $77 a barrel.

Banking giant Credit Suisse has said the price could fall to $71, while Charles Ebinger, of the Brookings Institution, said he expects prices to fall to $60 to $70 before stabilizing.

David Dismukes, executive director of the LSU Center for Energy Studies, said a correction in the crude price was to be expected.

U.S. oil production jumped from 5 million barrels of oil per day in 2008 to 8.5 million in 2013.

Commodities markets have ignored the increase in shale production in the United States even as the barrels stacked up at refineries. Analysts kept saying Third World economic growth, particularly in China, would increase oil consumption. But with Europe’s recovery slipping and the economies of Asia and China growing much more slowly than expected, that mind-set has changed.

“Now they’re saying, ‘Well, wait a minute. Hmm. Maybe we do have enough crude oil out in the market. Maybe these prices are too high,’ ” Dismukes said.

Still, Dismukes said he would be surprised to see crude prices fall below $75 a barrel, and “very, very surprised” if prices dropped below $70.

While the finding cost for a barrel of oil in Saudi Arabia is a fraction of that in the United States, the break-even price is similar.

“They need $70, $80, $90 to keep their governments running. That’s their break-even price,” Dismukes said. “So I suspect there will be some OPEC reaction before too terribly long.”

OPEC is a cartel made up of 12 oil-producing countries that works to maintain production quotas among its members to help control prices.

Scott said Saudi Arabia’s impatience with other members of the Organization of Petroleum Exporting Countries has played a part in oil’s declining price.

OPEC produces about 30 percent of the world’s oil. Members prop up the price by limiting their production, he said. But right now, Libya is cheating on its quota “like crazy,” and so are a couple other OPEC members.

Saudi Arabia traditionally cuts its production to offset the cheaters. But the kingdom recently upped its production to bring the other members in line, and that resulted in the sudden price drop.

If the Saudis succeed, the low prices will be short-lived, Scott said. If not, Credit Suisse’s projection of $71 per barrel may be correct, and that will be a longer-term problem.

The International Energy Agency told Bloomberg News that OPEC was trying to find out how much of a price drop North American producers can bear.

Reuters described it differently. Saudi Arabia, the news agency said, has effectively started a “global price war.”

But Briggs said OPEC’s statements about oil prices are just political posturing.

OPEC has far less influence over the price than members want the world to believe, he said.

Chris John, president of the Louisiana Mid-Continent Oil and Gas Association, said the current oil price shows how big an impact the increase in U.S. production is having.

In the past, any one of the recent conflicts globally, whether Israel-Hamas, the Islamic State in Iraq or Russia-Ukraine, would have been enough to cause an enormous spike in oil prices, he said. But even with all those conflicts, the price of crude continues to fall.

The U.S. is producing record levels of oil and nearing the long-stated goal of energy security, he said. The country also is much closer to seeing exports of U.S. oil, which have been banned since the energy crisis of the 1970s.

“I think you’re going to see a major push by a lot of folks to start opening that up,” John said. “We just can’t handle all the oil that we’re producing.”

Brookings estimates if exports were allowed, the U.S. would immediately begin shipping 1.7 million to 2.5 million barrels per day, and that would further drive down prices.

Follow Ted Griggs on Twitter, @tedgriggsbr.