When Samson Resources Corp. filed this year's biggest energy-related bankruptcy in September, the oil and gas company said it had a deal to emerge from Chapter 11 protection by year-end. Just a few weeks later, plunging gas prices had left the deal in tatters.

Samson joins about a half dozen troubled energy producers that have sought court protection from creditors this year and discovered asset values have evaporated or that a restructuring plan has unraveled as commodity prices plunge, according to a Dec. 1 report.

Bankers, lawyers and advisers involved in the cases blame the steep drop in energy prices and the industry's huge need for constant, capital-intensive drilling and exploring to sustain production.

In the past 16 months, the price of oil has sunk to around $40 per barrel from about $100, ending years of elevated crude prices that fueled oil companies' debt-financed expansion.

"It can be a really tough spot especially when you have the bottom drop out," said Michael Cuda, a bankruptcy lawyer with Squire Patton Boggs in Dallas, who represents a lender in the Samson case.

"A lot of assets suddenly become valueless," he said, speaking of energy companies generally.

Samson declined to comment.

Many of the energy companies now in Chapter 11 are among the weakest players, but their experience serves as a warning that the dozens of their peers struggling to remain afloat may find their assets quickly depleted in bankruptcy, dishing out heavy losses to investors.

Bankruptcy is supposed to be a relatively brief refuge while a company works out a turnaround.

Quicksilver Resources Inc. (OTC: KWKAQ) entered bankruptcy in March and in September presented creditors a turnaround plan, according to court documents. Yet two weeks later the oil-and-gas producer changed course, saying rapidly dwindling assets forced it to sell its business.

Quicksilver did not immediately respond to a request for comment.

Fire-Sale Prices

Energy companies Dune Energy Inc., American Eagle Energy Corp. (OTC: AMZGQ) and BPZ Resources Inc. (OTC: BPZRQ) all filed for bankruptcy this year and have sold their assets at fire-sale prices. Another energy producer, Endeavour International Corp. (OTC: ENDRQ) filed last year, but suffered the same fate.

"Without access to new capital, the business deteriorates and literally eats itself," Samson's lawyer, Joshua Sussberg, said at Samson's first U.S. Bankruptcy Court hearing.

Businesses always lose value in bankruptcy, but the declines in energy have been striking.

KKR & Co. led a buyout of Samson in 2011 for $7.2 billion. The company estimated its value at less than $1.5 billion for its prearranged bankruptcy plan.

Dune Energy valued its assets, including about 15.52 million barrels of oil equivalent of reserves, at $229 million in September 2014. The company auctioned them during its bankruptcy for $19 million in July.

Houston-based BPZ Resources fetched less than $10 million for its assets in July, which included licenses to explore for oil and gas covering 1.9 million acres (7,690 square kilometers) in Peru. Last year it valued the assets at $291 million.

Dune and BPZ did not immediately respond to requests for comment.

William Snyder of Deloitte CRG, who advised Dune Energy, said stakeholders and professionals running these cases have been blindsided by tumbling asset values.

"When energy and production companies run out of money, they get really ugly," he said. One problem is the loss of veteran employees, who take with them key know-how. "The assets get tainted. They go to auction, and it's like, how could that happen?"

Prior to bankruptcy, companies borrowed heavily against their assets, which means steep losses for creditors when the assets are sold for pennies in bankruptcy.

American Eagle Energy, which explores for energy in North Dakota, issued $175 million in bonds in August 2014. The company filed for bankruptcy in May, estimating its assets were worth $211 million. It sold them in October for under $37 million.

American Eagle declined to comment.

Adding to energy companies struggles are battles among creditors.

When prices stabilized earlier this year, hedge funds that seek to profit by investing in deeply troubled companies swooped into the energy sector. Many suffered when commodity prices resumed their decline.

"People who invested early got crushed," said Emanuel Grillo, a bankruptcy attorney at Baker Botts.

Many of those distressed investors are now nursing big losses when the companies only have enough value to pay the creditors ahead of them. As a result, many of the energy bankruptcies involve battles not just between the company and its creditors, but also fights between lenders and bondholders.

In the Samson Resources case, junior bondholders say the lenders have lost the right to get repaid ahead of them because their collateral no longer has value, drawing a major battle line in the case.

Becky Roof of AlixPartners, who advises distressed energy companies, said the experience with energy bankruptcies so far partly reflects the type of companies filing: weak, with far too much debt. She said stronger companies will fail next year if energy prices remain low.

Not all energy-related companies have languished in bankruptcy. Oil services firm Hercules Offshore Inc. (NASDAQ: HERO) and exploration company Milagro Oil & Gas Inc. were both in and out of bankruptcy in weeks to seal deals negotiated prior to filing.

"Hercules, they were really smart," said Roof. "They filed while they still had liquidity and that is going to serve them really well."