North of Norway: A Natural Lab
A seafloor mud volcano north of Norway is presenting researchers around
the globe with new and intriguing questions about Earth's underwater
world and about the potential for life on other planets.
Mud volcanoes, generally similar to regular volcanoes, erupt a watery or
gassy mud instead of hot, molten rock. The Haakon Mosby mud volcano (HMMV),
named for the famous Norwegian oceanographer, is considered especially unusual
because of its Arctic location, its development largely within glacial marine
sediments, and the presence of what appears to be methane hydrate within
the volcano's surface.
According to Peter Vogt, a Naval Research Laboratory scientist who has
studied HMMV extensively, the discovery of the mud volcano in 1989 was "as
much serendipity as science, since no one predicted its existence." The
structure's unique characteristics and the strange life forms living on
its surface captivated scientists, and a return trip to HMMV was scheduled
for 1996. The 1996 research team, supported by NSF's Office of Polar Programs,
comprised scientists and collaborators from various U.S., Norwegian and
The 1996 HMMV data revealed a warm center surrounded by mounds
and depressions, and encircled by a 200-meter-wide shallow moat.
Tubeworms lie on the volcano's outer flanks, apparently living
off of the methane within. HMMV is also home to numerous bottom
fish and almost 20 new species of organisms. According to Vogt,
the ecosystem is a scientist's dream come true, an "unexcelled
natural laboratory." He adds, "Ecosystems such as those
found on HMMV may be the most likely analogs to other life in
the solar system, possibly on the ice- and maybe ocean-covered
Jovian moon, Europa."
The vast reservoir of methane trapped within or below the oceans' widespread
hydrate-cemented sediment could become a major fossil fuel source. Also
known as "swamp gas," methane is a clean-burning fuel. If, however,
the methane releases from its hydrate "cage," the movement may
trigger submarine landslides. Because methane is also a powerful greenhouse
gas, it may be a major factor in future climate change.
Vogt is quick to point out that the presence of methane hydrate has introduced
many scientific mysteries, and that further research is critical. "Is
what we photographed actually methane hydrate or is it bacterial mats?" he
asks. "What are the shape and fluxes of the methane plumes we detected
in the ocean above? Can we use these plumes to model deep water dynamics?
And, finally, how can we make use of our knowledge? Could such hydrothermal
vents some day be used as 'gas stations' to refuel unmanned underwater vehicles?"
NSF may help fund another visit to HMMV, hopefully to find answers to these
questions. Once again uniting researchers from several countries, the planned
summer cruise is set for the MSTSLAV KELDYSH, with its two MIR submersibles
made famous in the movie "Titanic."