National Oceanic and
Atmospheric Administration
United States Department of Commerce

What's New

Methane hydrate deposit and gas
June 06, 2018

EOI scientists aboard E/V Nautilus June 12-29 used multibeam sonar and a remotely operated vehicle to more fully document and characterize the undersea methane sites from Northern California to Washington.  Up until a few years ago, only 100 methane “seep sites” had been identified primarily by fisherman using their fish-finders observing the acoustic reflections of the gas bubbles.  Beginning in 2016, EOI scientists began a more systematic mapping of the seeps using new sonar technology on the E/V Nautilus, owned and operated by the Ocean Exploration Trust.  About 25 percent of the potential methane seep water column area has now been mapped and analyzed. This year, EOI researchers embarked again on the Nautilus to continue surveying additional methane sites by night.  During the day a remotely operated vehicle (ROV) colleted samples of gas, methane hydrate, seep water, fauna and rocks at these sites.  Analyzing these samples in conjunction with a more complete inventory of sites will help scientists understand the origin of the seeping methane and its impact on the ocean environment.

More information about the Cascadia Margin expedition:

More information about the methane research and expedition can be found at:

NOAA PMEL EOI Program Methane Studies:

Oregon State University Press Release:

Research Sites

Axial Seamount

Cascadia Margin


Lau Basin

Kermadec Arc

Explorer Ridge

Ring of Fire

Youtube channel  EOI Channel


NOAA's Team Player of the Month: EOI's Susan Merle! See NOAA-PMEL's awards site

2016 NOAA-OAR Outstanding Scientific Paper Award: EOI's Resing, J.A., P.N. Sedwick, C.R. German, W.J. Jenkins, J.W. Moffett, B.M. Sohst, and A. Tagliabue (2015). Basin-scale transport of hydrothermal dissolved metals across the South Pacific OceanNature 523, 200–203