Washington, D.C. ? Government scientists believe Alaska’s North slope has huge deposits of frozen natural gas that current technology could extract, according to an Interior Department report.

The study by scientists at Interior’s U.S. Geological Survey estimates that more than 85 trillion cubic feet of natural gas in the form of gas hydrates – methane gas locked in water as an ice-like solid – eventually may be recoverable from Alaska’s North Slope, both on shore and in coastal waters.

The abundance of methane hydrates in nature, both in the Arctic region and in ocean sediment, has been known for decades. The study released Wednesday is the first assessment of the largest U.S. technically recoverable concentration of gas hydrates.

The report cautioned, however, that further research including long-term production tests will be needed to determine whether such development will be economical.

Scientists also are uncertain about what impact the disruption of the frozen methane gas may have on global warming.