CHICAGO, (Reuters) – As much as 1 million times the  normal level of methane gas has been found in some regions near  the Gulf of Mexico oil spill, enough to potentially deplete  oxygen and create a dead zone, U.S. scientists said yesterday.

Texas A&M University oceanography professor John Kessler,  just back from a 10-day research expedition near the BP Plc oil  spill in the gulf, says methane gas levels in some areas are  “astonishingly high.”Kessler’s crew took measurements of both surface and deep  water within a 5-mile (8 kilometer) radius of BP’s broken  wellhead.“There is an incredible amount of methane in there,”  Kessler told reporters in a telephone briefing.

In some areas, the crew of 12 scientists found  concentrations that were 100,000 times higher than normal.

“We saw them approach a million times above background  concentrations” in some areas, Kessler said.

The scientists were looking for signs that the methane gas  had depleted levels of oxygen dissolved in the water needed to  sustain marine life.

“At some locations, we saw depletions of up to 30 percent  of oxygen based on its natural concentration in the waters. At  other places, we saw no depletion of oxygen in the waters. We  need to determine why that is,” he told the briefing.

Methane occurs naturally in sea water, but high  concentrations can encourage the growth of microbes that gobble  up oxygen needed by marine life.

Kessler said oxygen depletions have not reached a critical  level yet, but the oil is still spilling into the Gulf, now at  a rate of as much as 60,000 barrels a day, according to U.S.  government estimates.