The year could not have ended any more differently than it began for the Tuscaloosa Marine Shale and the companies developing the oil-rich formation.

At the time, a barrel of oil was fetching about $100. Energy firms, led by Goodrich Petroleum and its $300 million, 32-well drilling program, were beefing up exploration programs. As many as 60 wells might be drilled by all the energy companies working in the formation.

Analysts believed drillers were on the cusp of solving the production riddle in the shale, where the oil-bearing rock frequently closed off fractures and slowed the flow of crude. Drillers also were moving to reduce the cost of wells — the most expensive among U.S. shale formations — and make working in the TMS more profitable. The formation stretches across Louisiana and into Mississippi. Access to the TMS mother lode, estimated at anywhere from 7 billion to 20 billion barrels of oil, had never looked closer.

“2014 will be a very big year for the TMS … if plans materialize as expected,” Goodrich President Robert Turnham said in February.

In June, with oil prices above $100 a barrel, private equity firm Apollo Global agreed to invest as much $400 million to develop Halcón Resources Group’s Tuscaloosa acreage. The deal was expected to help drive development in the formation. Halcón also said it planned to develop an oil-handling facility in Natchez, Mississippi, to help handle production.

But oil prices began slipping that month and the slide has yet to end. The price of crude spent Christmas week at less than $60 a barrel, reaching a five-year low of $55.25.

As oil prices dropped, Goodrich, Halcón and other major players in the Tuscaloosa saw their stock prices, and their 2015 drilling budgets, take a beating. Goodrich plummeted from nearly $30 a share in June to less than $5 in December. Halcón peaked at $7.42 a share in July and fell to less than $2 in December.

As share and oil prices fell, drillers began hacking major chunks from their drilling programs.

The Tuscaloosa, where analysts say $80 oil is needed to break even, was one of the first casualties.

Goodrich announced it would spend $150 million to $200 million to drill in 2015, with almost all of that in the TMS. Halcón cut its drilling budget by $200 million to $750 million, but the company said it didn’t plan to spend any of that money in the Tuscaloosa. Sanchez Energy also said it was taking a step back from the Tuscaloosa.

On the plus side, the formation is still in such an early stage of development that a slowdown doesn’t have much economic impact. But the Tuscaloosa could generate an economic boom that would dwarf that of the natural gas-rich Haynesville Shale in northwest Louisiana.

Economists, local officials and industry members have said the Tuscaloosa could generate thousands of high-paying jobs as well as revenue and jobs for businesses that will service the oilfield workers.