Major Drilling Ship Back at Sea
JOIDES Resolution to Range from Bering Sea to Antarctic
After a major overhaul, one of the world’s two major scientific deep-sea drilling ships is back at sea. Much of the coming year’s research aboard the JOIDES Resolution will focus on sudden climate shifts and sea-level changes of the past--work that will help scientists understand how such phenomena may affect earth in the future.
Under the international Integrated Ocean Drilling Program, the United States and Japan operate two vessels--the JOIDES Resolution (known by scientists and crew as the JR) and the Chikyu—that drill out and remove cores from the ocean bottom. The cores are used by scientists around the globe to study earth’s climate and geological history. The Chikyu is relatively new, but the JR, converted to research use in 1984, has spent most of the last two years in a Singapore shipyard, as mechanics rebuilt it from bow to rig. The $130 million renovation was funded by the U.S. National Science Foundation (NSF). Two institutions supervise its scientific work: Texas A&M University, which catalogs the cores; and the Borehole Research Group at Columbia University’s Lamont-Doherty Earth Observatory, which develops and deploys instruments lowered into the cored holes to measure the natural properties of the rock and sediment.
The vessel is now running through test trials above the Ontong-Java Plateau in the Southwest Pacific. "It's comforting and exciting to know the JR has been refit and is out there," said geophysicist David Goldberg, head of the Lamont borehole group.
By early March the ship will set sail from Honolulu to spend four months drilling near the equator in the middle of the Pacific Ocean. With Lamont scientists Helen Evans, Alberto Malinverno and Trevor Williams on board, scientists will be searching for clues about temperatures on earth from about 55 million years ago, when modern-day mammals emerged during the warm Eocene, to 3 million years ago, when ice sheets covered parts of the earth. “From the greenhouse world to the ice-house world,” Williams calls the time frame.
Tiny plankton fossils buried in the ocean floor will help the scientists reconstruct sea temperatures from those times. The plankton thrived in the nutrient-rich water and sank to the bottom. By analyzing their shells, scientists can tell when the animals lived and what the climate was like.
The extreme warming and cooling that took place during that era may hold lessons for humanity in the future, said Williams. “We’re learning about how the earth operates in warmer conditions,” he said. “Once you know how the system works and its past extremes, it’s possible to find analogs to where we’re headed.”
|In its initial mission, the ship will drill eight Pacific Ocean sites north of the equator|
In July, the ship will sail north for climate research in colder waters: the Bering Sea, north of Japan. From there, the ship travels to the Shatsky Rise, a mountainous plateau of basalt near the coast of Japan, to study plate movement and magma formation. Its last two scheduled legs, in late 2009 and early 2010, will be in the Canterbury Basin off New Zealand, and Wilkes Land off Antarctica, where it will study changes in sea level.
A technical crew operates the drilling equipment, while a team of about 30 scientists analyzes the cores brought on deck, as well as data from the “downhole” instruments. The JR has drilled down as far as two kilometers below the sea floor, in up to six kilometers of water. Unlike a commercial oil rig, which is tethered to a platform while drilling, it travels freely. "It can go nearly anywhere," said Goldberg.
“The research pursuits of thousands of scientists around the globe will be enhanced in a major way by the future work,” said Robert Gagosian, who heads the Consortium for Ocean Leadership, the contractor hired by NSF to oversee financing of research projects aboard the ship.
“We are extremely pleased to see the JOIDES Resolution set sail once more for science – with a vastly improved capability for performing cutting-edge research into the secrets of earth's past climate, past ocean conditions, deep biosphere and interior,” says Tim Killeen, NSF assistant director for geosciences. “NSF congratulates all involved in the successful refit and modernization of this major research platform.”
- TAGS:Ocean Drilling