A new type of deep-sea robotic vehicle called Nereus has reached the deepest part of the world’s ocean—the Mariana Trench 6.8 miles below the surface in the western Pacific Ocean.
Nereus is a hybrid—an unmanned vehicle that can be remotely operated by pilots aboard a surface ship via a lightweight, micro-thin, fiber-optic tether or switched into a free-swimming, autonomous vehicle.
The first vehicle to explore the Mariana Trench since 1998, the Woods Hole Oceanographic Institution’s Nereus performed well during a two-week engineering test cruise on the University of Hawaiʻi’s R/V Kilo Moana.
UH geologist and co-chief scientist for the expedition, Patricia Fryer was on board to examine samples retrieved during each remotely operated dive along with colleagues from Woods Hole and Johns Hopkins University.
“The samples include sediment from the subducting and overriding tectonic plates that meet at the trench and, for the first time, rocks from deep exposures of Earth’s crust close to mantle depths south of the Challenger Deep,” says Fryer. Integrating laboratory analyses with new mapping data will “tell a story of plate collision in greater detail than ever before accomplished in the worlds oceans,” she adds.