Drilling deeper in search of life's origins

A ship that has spent decades trying to drill à nearer to the earth's mantle is preparing for a new voyage to uncover clues to how life began.

- Dominique Mosbergen

Two dozen geologists, microbiologists and other scientists will sail in April from Portugal aboard the Joides Resolution, a former oil drill ship turned research vessel, to the Atlantis Massif, a 14,000-foot underwater mountain rising from the floor of the Atlantic Ocean.

They plan to deepen a 4,640-foot hole drilled nearly 20 years ago to 6,750 feet. The hole won't be the longest in the seafloor, but it would push closer than ever to the mantle and plumb deeper layers of ocean crust that haven't been reached before. At the new depth, temperatures are expected to exceed 400 degrees Fahrenheit.

"It's going to get hot," said geologist Peter Blum, the expedition's project manager. "This is new territory."

Deepening the hole will be hard. Engineers on the ship plan to lower heavy drilling tools through about 5,400 feet of water to find a hole on the seafloor that is about 15 inches wide. Joides engineers compared the process to standing on a chair and trying to lower a pencil tied to the end of string into the mouth of a soda bottle with a fan blowing.

Adjacent to the mid-Atlantic Ridge, the Atlantis Massifis a tectonic window, where the tectonic plates spread apart and pull the earth's deeper layers to the surface. By drilling at tectonic windows, scientists can examine parts of the earth's inner structure that would otherwise be inaccessible.

"It's almost a way of cheating the system," said Jason Sylvan, a biological oceanographer at Texas A&M University.