CORVALLIS - An international team of researchers has discovered a deposit of methane gas hydrates on the seafloor off Newport, Ore.
Although the material looks like snow or ice, it is so packed with methane, it can be set on fire, said Robert Collier, an Oregon State University associate professor of oceanic and atmospheric sciences, who helped identify the substance as it was hauled from the sea.
The finding is important, scientists say, with implications in the areas of energy development, global warming, and the marine food chain.
"This is a rare find," Collier said. "You can virtually count on one hand all of the people in the world who have ever seen this much material."
Undersea methane hydrate is significant as a possible future fuel source. As it decomposes, undersea methane could also add an energy source for undersea microorganisms, and, finally work its way out of the water and into the atmosphere, accelerating global warming.
German, U.S. and Canadian scientists discovered the deposits during a project to study fluids and gases which are being squeezed from sediments on the seafloor off the Pacific Northwest and Alaska. The expulsion, active along the plate collision boundaries of the earth, results from the compression of the water-rich sediments carried on the moving oceanic plates that are diving below the continents.
The joint project is coordinated by GEOMAR, Research Center for Marine Geoscience at the University of Kiel, Germany. GEOMAR director, Erwin Suess, a former OSU oceanographer, was chief scientist during the expedition.
A giant, TV-guided robotic "claw" working from the German research vessel Sonne 50 miles west of Newport retrieved more than 100 pounds of the material from the seafloor. The hydrates were formed in the sea under conditions of high pressure and low temperatures, Collier said. They begin to decompose as soon as they are removed from the seafloor, within hours leaving scientists with only a smelly puddle of water.
The fact that methane hydrates are only stable under narrow temperature and pressure conditions and are generally buried deep beneath the seafloor may limit potential commercial uses of the compound. But the study of these methane hydrates also has enormous implications in other fields, Collier pointed out.
Some researchers believe that global warming - which is expected to be most severe in polar regions where vast quantities of shallow gas hydrates are present -could lead to the catastrophic decay of these deposits. Decomposition of the hydrates could release more methane and cause further global warming, scientists warn.
Scientists from OSU's College of Oceanic and Atmospheric Sciences and the University of Victoria in British Columbia participated in the recovery and analysis of the gas hydrates.
Gary Klinkhammer, an OSU geochemist and associate professor of oceanic and atmospheric sciences, said the discovery of this large methane hydrate field is only the first step in what may be a series of important research projects.
"This site presents an incredible opportunity," Klinkhammer said. "Located less than 50 miles off Newport, this could be a natural laboratory to study the behavior of this unique and globally significant material."
Samples from this new site will give the first accurate estimates of the layering and proportions of hydrate and sediment that generate seismic reflections from below the seafloor, Collier said. From those seismic readings, scientists surmise that there are vast deposits of the hydrates located throughout the world.
Although its potential as a viable fossil fuel resource is unknown, Japan recently announced a $50 million effort to commercially produce methane from the sea surrounding Hokkaido.
"We need eyes on the deep-sea floor to further advance marine science," Suess said. "Discoveries of such a basic nature in deep-sea research are only made possible by the application of new technologies including remotely operated, autonomous, and manned submersibles.
"When these and other TV-guided instrumentation are supported by state-of-the-art remote sensing and analysis from surface ships and shore-based laboratories," Suess added, "we are capable of making incredible progress in understanding critical scientific and environmental issues."