Subseafloor Observatories Installed to Run Dynamic Experiments

2016-06-29T10:44:14+00:00 September 7, 2010|

(Click to enlarge) A welder works on a “reentry cone,” which is used to guide drill pipe into the ocean floor. (Credit: IODP)

Scientists will study fluid flow, chemistry, and life off British Columbia Coast

Victoria, Canada – An international team of scientists has just returned from two months at sea near British Columbia, Canada, where they installed two observatories in the ocean floor to run innovative experiments at the bottom of the sea.

The Integrated Ocean Drilling Program (IODP) “Juan de Fuca Ridge-Flank Hydrogeology” Expedition left Victoria July 9 and returned September 5. Using the scientific research vessel JOIDES Resolution, the team drilled boreholes nearly 530 meters deep (nearly 1,800 feet) into the ocean floor to install the observatories.

“The ocean crust is the largest aquifer on the planet. We know it’s made up of many sections, but we have no idea how these parts connect or how they interact with one another,” says co-chief scientist Dr. Andy Fisher of the University of California at Santa Cruz.

(Click to enlarge) Engineer Bob Aduddell (IODP-USIO/ Texas A&M University) and geochemists Samuel Hulme (University of Hawaii at Manoa) and Geoff Wheat (University of Alaska Fairbanks) work on the deck of the JOIDES Resolution to prepare a CORK observatory before deployment into the ocean floor. (Credit: IODP)

The observatories, known as “CORKs” (because they are used to seal boreholes), were installed 200 kilometers (125 miles) west of Vancouver Island, Canada. Each CORK is packed with scientific instruments that collect samples and data at multiple depths to learn more about the water, pressures, temperatures, chemistry, and microbiology within the rocks and sediments of the ocean crust. The CORKs are being used as part of a sampling and monitoring network to allow scientists to determine the properties of the ocean crust, and to better understand how water, heat, and chemicals are transported across vast distances below the bottom of the ocean.

The volume of salt water in the ocean crust is comparable to the volume of fresh water in Earth’s ice caps and glaciers – about 20-30 million cubic kilometers. For comparison, this is about 2000 times greater than the global fresh water supply, and about a half million times greater than annual fresh water usage in the U.S.

Like fresh water on land, the salt water below the seafloor is in motion, moving rapidly from place to place. Until now, scientists have never been able to “tag” water in one place below the seafloor and determine where it flows. Experiments begun during the IODP Juan de Fuca Ridge-Flank Hydrogeology Expedition will provide the first direct evidence of active flow pathways and rates in the ocean crust.

(Click to enlarge) Beth Orcutt (Microbiologist/Organic Geochemist, Aarhus Universitet, Denmark) presents CORK microbiology experiments to colleagues at a science meeting during the expedition. (Credit: IODP)

Researchers used the boreholes to run experiments during the expedition. In one experiment, they injected benign tracers into the ocean floor to track the directions, rates, and patterns of fluid flow within the seafloor.

In another experiment, microbiologists placed chips of rocks and minerals in the CORKs to identify microorganisms living in the seafloor. “It’s like lowering an empty hotel into the borehole,” explains co-chief scientist Takeshi Tsuji of Kyoto University, Japan. “When the chips are recovered in a few years, we will learn who moved in.” Scientists estimate that a large fraction of life on Earth thrives in the “subsurface biosphere.” Once identified, the microorganisms from the CORKs will be matched to pressure and temperature data to determine the physical conditions that are most favorable to life at different depths.

(Click to enlarge) One of the CORKs on the rig floor of the JOIDES Resolution, ready to be deployed. (Credit: IODP)

Fisher and his team will recover CORK samples and data and run additional experiments next summer and in later years. “Through monitoring and experiments with CORKS, we will learn how microorganisms may have developed on Earth, which offers insight into how life may develop on other planets. We’ll also learn how carbon is transported and might be stored within deep reservoirs,” he says.

Three educators, an engineering student, a computer graphics animator, and an artist from the U.S. and France joined the expedition to develop tools to share the expedition’s goals with non-academic audiences. The team created written, photographic, audio and visual logs of expedition activities, participated in video conferences with museums and schools, and wrote classroom activities and experiments for students on shore.

Canadian Scientist Leads Next Expedition

(Click to enlarge) The IODP Juan de Fuca Ridge-Flank Hydrogeology expedition was led by co-chief scientists Takeshi Tsuji (Kyoto University, Japan) (left) and Andy Fisher (University of California, Santa Cruz) (right) and Expedition Project Manager Katerina Petronotis (IODP-USIO/Texas A&M University) (center). (Credit: IODP)

The JOIDES Resolution embarks on its next expedition on September 9. Led by Dr. Earl Davis of Canada’s Pacific Geoscience Center, the “Cascadia ACORK” expedition will install a new CORK observatory in the Cascadia subduction zone, about 75 km off the coast of Vancouver Island to monitor changes in pressure associated with this seismically active setting, and to understand the formation of gas hydrates – ice-like deposits of gas commonly found below the ocean floor.  In a year, the new CORK will be connected to the NEPTUNE-Canada deep-ocean cable network, which will provide power and real-time data collection over the coming decades. An onboard education program, “School of Rock,” will teach 20 educators about marine geoscience. Davis and colleagues will return to Victoria on September 19, 2010.

About IODP

(Click to enlarge) IODP Expedition 327 map. (Credit: IODP)

The Integrated Ocean Drilling Program (IODP) is an international research program dedicated to advancing scientific understanding of the Earth through drilling, coring, and monitoring the subseafloor. The JOIDES Resolution is a scientific research vessel managed by the U.S. Implementing Organization of IODP (USIO). Together, Texas A&M University, Lamont-Doherty Earth Observatory of Columbia University, and the Consortium for Ocean Leadership comprise the USIO.  IODP is supported by two lead agencies: the U.S. National Science Foundation (NSF) and Japan’s Ministry of Education, Culture, Sports, Science, and Technology. Additional program support comes from the European Consortium for Ocean Research Drilling (ECORD), the Australian-New Zealand IODP Consortium (ANZIC), India’s Ministry of Earth Sciences, the People’s Republic of China (Ministry of Science and Technology), and the Korea Institute of Geoscience and Mineral Resources.

Useful Websites

For more information about IODP Expedition 327 – Juan de Fuca Ridge-Flank Hydrogeology, visit http://iodp.tamu.edu/scienceops/expeditions/juan_de_fuca.html

To view a video of a CORK and its different components, visit http://www.youtube.com/watch?v=KbZTVIeRX2A

For more information about the JOIDES Resolution, visit www.joidesresolution.org.

For more information about the Integrated Ocean Drilling Program, visit www.iodp.org.

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Media Contacts:

Kris Ludwig
Consortium for Ocean Leadership
kludwig@oceanleadership.org

1-202-448-1254 / 1-206-293-5384 (mobile)

Miyuki Otomo
Integrated Ocean Drilling Program Management International, Inc. (IODP-MI)
motomo@iodp.org

+81-3-6701-3188