NSF PR 02-73 - September 10, 2002
Scientists Explore Large Gas Hydrate Field off
Details emerge of possible new energy source
Ocean Drilling Program (ODP) scientists have completed
a two-month expedition off the coast of Oregon to
investigate the origin and distribution of frozen
deposits of natural gas known as "gas hydrates." Funded
largely by the National Science Foundation (NSF),
their research could identify locations and quantify
amounts of this potential natural resource, which
may eventually serve as a major new worldwide energy
Among the most surprising findings of the recent offshore
drilling was the fast rate at which gas hydrate is
forming. When hydrate forms rapidly, the salts in
the surrounding seafloor sediments do not have time
to diffuse and the water in the sediment becomes saltier
than seawater. Scientist Marta Torres of Oregon State
University explained, "We observed high concentrations
of sea salts in the upper 10-15 meters of sediment,
indicating that hydrate is forming very rapidly below
the seafloor in this region."
Although scientists know that gas hydrates are common
in the seafloor on the margins of continents around
the world, they do not know how much hydrate is present.
Scientists onboard the research vessel JOIDES Resolution
studied the deposits in an area known as Hydrate Ridge
to determine how much gas hydrate is present beneath
According to Paul Dauphin, ODP program director at
the National Science Foundation, "Gas hydrates have
been known to scientists for some time, but were previously
avoided because of potential safety problems. Through
a better understanding of how to drill in such environments,
ODP is developing tools and strategies to discover
the full extent of gas hydrate deposits."
Anne Trehu of Oregon State University (USA), a co-chief
scientist on the cruise, said, "Measurements made
during this cruise will allow us to update estimates
of the volume and flux of methane and other hydrocarbon
gases trapped in the sediments on the Oregon continental
margin and, by extension, in other regions."
Ocean drilling plays a critical role in addressing
questions about hydrates because it provides the only
means available of directly sampling the material
and the sediments that host them deep beneath the
seafloor. In 1995, ODP researchers drilled into gas
hydrates in a relatively stable area off the U.S.
east coast. Scientists have estimated that area could
contain enough methane to supply U.S. energy needs
for more than 100 years. They also found evidence
suggesting that hydrates are involved in the global
climate cycle, and that they can cause massive landslides.
On the recent cruise, scientists also gained an understanding
of the importance of sediment composition and grain
size in the distribution of hydrates within the sediments,
which may provide clues to their locations.
ODP is an international partnership of scientists and
research institutions organized to study the evolution
and structure of the Earth. While ODP is funded primarily
by the US National Science Foundation and its international
partners, the US Department of Energy and the European
Commission played important roles in funding much
of the innovative technology used on this expedition.
The Joint Oceanographic Institutions manages the program.
Texas A & M University is responsible for science
operations, and Lamont-Doherty Earth Observatory of
Columbia University is responsible for logging services.
Photographs from the expedition off the coast of Oregon
are available on the web at: http://www-odp.tamu.edu/public/life/leg204.html