Energy companies used to avoid methane hydrates no matter what. Now the industry may be drilling right into danger.
BP, Transocean and Halliburton are placing the blame for the disaster on each other.
The rush to produce more oil has led companies to take more risks, including drilling in areas with methane hydrates.
Methane hydrates could make the seafloor unstable, or turn into methane gas and ignite the rig.
The blame-game has reached hurricane force.
On Capitol Hill, executives from BP, Transocean and Halliburton are pointing fingers at each other, while in Louisiana, Coast Guard officials are grilling lower-level managers from the same companies. But the rush to figure out went went wrong from an engineering perspective misses the bigger picture, experts say.
The decision by BP and many other energy companies to drill through areas of unusual ice-like crystals -- called methane hydrates -- is a risky one fraught with huge consequences for failure.
"Methane hydrates are a geological hazard, and it's been well established for decades that they are dangerous," said Richard Charter, head of the Defenders of Wildlife marine program and member of the Department of Energy's methane hydrates advisory panel. "Until 10 or 15 years ago, the industry would avoid them no matter what."
Now, Charter said, the rush to produce more oil for domestic consumption has forced companies like BP to take bigger risks by drilling in deep waters that are a breeding ground of hydrates. And they worry that a new drilling push into the Arctic Ocean -- which President Barack Obama has authorized to begin next month -- could expose a fragile and remote environment to additional risks from catastrophic oil spills.
Methane hydrates only exist in cold water -- just above or below freezing -- and at the undersea pressures found in deep water off the continental shelf. "It's a lot like ice," said William Dillon, a retired marine geologist with the U.S. Geological Survey in Woods Hole, Mass. "The conditions that form them exist at the seafloor and in the sediments below."
This slushy mixture of sea water and methane gas makes drilling more complicated. For one, the presence of methane hydrates in sediment makes the seafloor unstable. That's why BP was using a high-tech drilling rig that was positioned like a helicopter on the surface.
And if hydrates are warmed by oil moving through pipes, they can turn into methane gas (known as "kicks" to drillers) that can shoot back up the drilling pipe and ignite the rig. Investigators are already focused on that scenario as a possible cause of the blast aboard the Deepwater Horizon rig on April 20.
Several marine geologists told Discovery News that the location of methane hydrate fields are well-mapped by petroleum companies and the Minerals Management Service, which regulates the industry. Researchers aboard scientific drilling ships say they avoid methane hydrate fields because of the inherent risks.
In 2003, Unocal abandoned plans to drill in the deep water off Indonesia for the same reason. China has delayed plans for offshore oil development after finding large hydrate fields, but many industry officials say they can engineer proper safeguards.
Arthur Johnson heads up Hydrate Energy International, a firm dedicated to exploiting the potential energy source of hydrates based in Kenner, La. He doesn't believe that they caused the blast.
"Based on everything I've seen, there's no way naturally-occurring hydrates had anything to do with loss of the well," Johnson said.
Methane hydrates only exist 3,000 to 5,000 feet below the seafloor, Johnson said. The BP drill went down to 18,000 feet.
Robert Bea, a civil engineering professor at the University of California, Berkeley, and oil industry consultant, disagrees. He's been interviewing workers who were aboard the rig before it blew and said the BP platform shut down several weeks before the accident because of hydrate problems.
"Whether it was either methane hydrate or gas, it doesn't really make a difference," Bea said. "It has unanticipated, undesirable effects. Based on my interviews and investigation, (methane) hydrate seeped into the core."
Bea and others say the industry's drilling and spill cleanup technology hasn't caught up with the economic imperative to produce more oil.
In June, Shell Oil plans a series of exploratory wells in the Beaufort and Chukchi Seas north of Alaska. That region is remote and lacks the kind of spill gear that is being deployed in the Gulf of Mexico. While the White House has delayed plans for oil drilling off the coasts of California and Virginia, the Alaska project is still on for now.
Eric Niiler is a freelance writer based in Washington, D.C.