The Neil Armstrong research vessel team extracts a core from the bottom of the Puerto Rico Trench

A team of scientists, engineers and crew on the research vessel Neil Armstrong operated by the Woods Hole Oceanographic Institution (WHOI) recently collected a 38-foot-long cylindrical sediment sample from the deepest part of the Puerto Rico Trench, nearly 5 miles below the surface. The sample core breaks records as the deepest core ever collected from the Atlantic Ocean, and possibly the deepest core collected from any ocean.

The event took place aboard a collaborative cruise in Puerto Rico between February and March 2022. The group responsible for the core collection was led by Professor Steven D’Hondt and Dr Robert Pockalny from the Graduate School of Oceanography and included researchers and technicians from WHOI, University of Rhode Island, University of California San Diego, Oregon State University, University of Washington, University of Puerto Rico Mayagüez and University of Munich.

Long sediment cores are usually collected by letting a central tube with a lead weight on top fall through the water and into the soft sediment that collects on the seabed over long periods of time. When the pipe is pulled from the seabed and brought up to the ship, the sediment recovered inside can be used to study environmental conditions and Earth’s climate dating back tens or hundreds of thousands, or even millions of years. years.

Scientists are also interested in understanding the genetic traits that allow microscopic organisms to survive in seafloor sediments. The main objective of this expedition was to better understand how microbes at different depths below the seafloor have adapted to very different environmental conditions present throughout the depth range of the trench. During three weeks at sea, the team collected core from a water depth of approximately 50 meters (165 ft) to the maximum depth of the trench of approximately 8,385 meters (27,510 ft) .

“We took these nuclei to learn how the microbes that live below the seafloor respond to pressure,” D’Hondt said. “Our ultimate goal is to improve understanding of how organisms in extreme environments engage with the world around them.” Our team’s success in extracting this core from the deepest part of the Atlantic Ocean will allow us to make a considerable advance in our understanding of this little-known part of life on Earth. »

The base collections were made possible by the long base system originally developed at WHOI in 2007 by then-research specialist Jim Broda for the research vessel. Knorr. After the ship’s retirement, the system was adapted to fit the slightly shorter ship Neil Armstrong. After this expedition, the long corer will be transferred to the OSU Marine Sediment Sampling Group, which is funded by the U.S. National Science Foundation and supports coring operations throughout the U.S. University Research Fleet, so that it can be put available to the entire oceanographic community.

“This achievement was only possible because of the phenomenal teamwork of everyone involved, including those who helped develop the Long Core Corer nearly 20 years ago,” said Rick Murray, Deputy Director of OMSI and vice president of science and engineering. “The fact that the long corer will pass into the capable hands of our friends and colleagues at Oregon State University means that it will have many more years of use by the ocean science community to help advance knowledge of our planet.”

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Material provided by Woods Hole Oceanographic Institute. Note: Content may be edited for style and length.