Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scripps Graduate Students Discover Methane Seep Ecosystem

30.07.2012
During a recent oceanographic expedition off San Diego, graduate student researchers from Scripps Institution of Oceanography at UC San Diego discovered convincing evidence of a deep-sea site where methane is likely seeping out of the seafloor, the first such finding off San Diego County.

Such "methane seeps" are fascinating environments because of their extraordinary chemical features and often bizarre marine life. The area of interest, roughly 20 miles west of Del Mar, is centered on a fault zone known as the San Diego Trough Fault zone. Methane, a clear, highly combustible gas, exists in the earth's crust under the seafloor along many of the world's continental margins. Faults can provide a pathway for methane to "seep" upward toward the seafloor.

The Scripps graduate students made the discovery during the recent San Diego Coastal Expedition (bit.ly/sdcoastex), a multidisciplinary voyage conceived and executed by Scripps graduate students. The cruise was funded by the University of California Ship Funds Program, which supports student research at sea and provides seagoing leadership opportunities.

While conducting surveys in search of methane seeps aboard Scripps' research vessel Melville, the graduate students mapped a distinct mound on the seafloor at 1,036 meters depth (3,400 feet), spanning the size of a city block and rising to the height of a two-story building. The area had been recommended by Jamie Conrad, Holly Ryan (U.S. Geological Survey) and Charles Paull (Monterey Bay Aquarium Research Institute), who surveyed the faults in 2010.

"Below the mound," described Scripps geosciences graduate student Jillian Maloney, "we observed a disruption in subsurface sediment layers indicative of fluid seepage."

The Scripps researchers then deployed instruments to collect sediment cores, gathering further evidence such as seep-dwelling animals, sulfidic-smelling black mud and carbonate nodules. These samples are currently being analyzed in Scripps laboratories for chemical clues and other telling elements of the environment.

Organisms collected from the site include thread-like tubeworms called siboglinids and several clams. Siboglinids lack a mouth and digestive system and gain nutrition via a symbiotic relationship with bacteria living inside them, while many clams at seeps get some of their food from sulfide-loving bacteria living on their gills.

While food is scarce in much of the cold, dark ocean depths, it is abundant at seeps due to the bacteria that proliferate around the methane source. Microbes there are eaten by worms, snails, crabs and clams, leading to a rich and productive community that helps sustain the surrounding deep-sea ecosystem.

"These chemosynthetic ecosystems are considered 'hot spots' of life on the seafloor in an otherwise desert-like landscape," said San Diego Coastal Expedition team member Alexis Pasulka, a Scripps biological oceanography graduate student. "New forms of life are continuously being discovered in these environments. Therefore, it is important to study these ecosystems not only to further appreciate the diversity of life in our oceans, but also so that we can better understand how these ecosystems contribute to overall ocean productivity and the carbon cycle."

Methane is a potent greenhouse gas, and researchers don't yet fully understand the magnitude to which seeping methane in the ocean contributes additional carbon to the atmosphere. Moreover, on many continental margins, frozen methane hydrates could represent a future energy source. Along the West Coast, methane seeps are known to exist off Oregon, California (near Eureka, Monterey Bay, Point Conception and Santa Monica), in the Gulf of California and off Costa Rica.

"This is a significant and exciting discovery in part because of the possibilities for future research at Scripps," said biological oceanography graduate student Benjamin Grupe, a member of the seep contingent on the San Diego Coastal Expedition. "The existence of a methane seep just a few hours from San Diego should allow Scripps scientists to visit frequently, studying how this dynamic ecosystem changes over days, months and years. Such regular data collection is difficult at most cold seeps, which rarely occur so close to ports or research institutions."

Grupe will lead a follow-up cruise in December that will revisit the newly discovered seep to collect additional samples and learn more about this ecosystem. The team of graduate students hopes to raise funds to employ technologies such as video-driven coring instruments and towed video cameras that will give them an up-close look at the methane seep.

The search for local seeps was one focus area of the multidisciplinary San Diego Coastal Expedition, which included teams of students investigating the oceanography and marine ecosystems off San Diego and led by chief scientist Christina Frieder. In addition to Grupe, Pasulka and Maloney, other members of the seep team included geophysics graduate students Valerie Sahakian and Rachel Marcuson.

R/V Melville, the oldest ship in the U.S. academic fleet, is owned by the U.S. Navy and has been operated by Scripps Oceanography for all of its 41 years.

"The students should be congratulated on their hard work and perseverance leading to this exciting find," said Lisa Levin, a Scripps professor who has studied methane seep ecosystems in most of the world's oceans. "Other scientists have suspected that methane seeps were present in the San Diego region, but these new data and samples provide the first convincing evidence. We know very little about what lives in deep waters-the planet's largest ecosystem-so it is not unexpected to find surprises on the deep-sea floor right in our own backyard. Having a 'local' seep should be a great boon to deep-sea research, education and public outreach at Scripps."

UC San Diego News on the web at: http://ucsdnews.ucsd.edu

Mario Aguilera | Newswise Science News
Further information:
http://www.ucsd.edu

More articles from Ecology, The Environment and Conservation:

nachricht Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen

nachricht A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

Im Focus: Silencing bacteria

HZI researchers pave the way for new agents that render hospital pathogens mute

Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...

Im Focus: Artificial Enzymes for Hydrogen Conversion

Scientists from the MPI for Chemical Energy Conversion report in the first issue of the new journal JOULE.

Cell Press has just released the first issue of Joule, a new journal dedicated to sustainable energy research. In this issue James Birrell, Olaf Rüdiger,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

IVAM’s LaserForum visits the Swiss canton of St. Gallen with the topic ultrashort pulse lasers

06.09.2017 | Event News

 
Latest News

Robust and functional – surface finishing by suspension spraying

19.09.2017 | Materials Sciences

The Wadden Sea and the Elbe Studied with Zeppelin, Drones and Research Ships

19.09.2017 | Earth Sciences

Digging sensors out of an efficiency hole

19.09.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>