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Scientists are drilling into the ocean’s ‘Lost City’ to find the origins of life — take a look

August 22, 20240
The ocean drilling vessel JOIDES Resolution recovered the mantle rock in spring 2023.

Thomas Ronge

Not far from the underwater mountain range the Mid-Atlantic Ridge, Lang watched a team of experts drill over a kilometer below the surface on the research vessel JOIDES Resolution.

“They made magic happen,” Lang said. Up to that point, people had only drilled into this type of rock to a depth of about 200 meters (0.12 miles), Lang said.

When Lang and the team surpassed 200 meters they were already extremely excited, but then the drill just kept going.

“Within a day we were at like 275 meters. And then three days later we were at like 500,” Lang said. They kept drilling until they reached a record depth of 1,268 meters.

Researchers obtained a record-breaking sample of mantle rocks.
The Lost City hydrothermal field includes carbonate towers that vent hydrogen and methane.

Susan Lang/U. of SC; NSF; ROV Jason; 2018 © WHOI

The researchers could have drilled just about anywhere on the seafloor, but they chose a site near the Lost City because its conditions may echo the environment present when life started forming.

The Lost City has what are known as carbonate towers made of limestone that stream out fluid between about 59 degrees to 239 degrees Fahrenheit, Lang said.

These fluids have high amounts of hydrogen. “Hydrogen is a really good fuel source, and so microorganisms can use it to fuel their metabolisms,” Lang said.

Perhaps it was crucial to early life forms, too.

If you want to know about Earth’s early days, you need to dig deep.
Johan Lissenberg and colleagues examining cores recovered from the Mid-Atlantic Ridge.

Lesley Anderson

The research team collected an over 4,000-foot core of a dense igneous rock called peridotite.

Because Lang and the team were working with samples that had never been exposed to the surface, it was important to preserve their subsurface conditions.

To do so, the team kept some rocks from being exposed to oxygen.

These samples from the deep give the researchers a better chance of seeing how molecules formed before photosynthesis started on Earth 3.5 billion years ago, Lang said.

Researchers want to grow microorganisms based on the rock samples
Researchers are continuing to study the recovered cores to look for clues about how life may have formed on Earth.

Lesley Anderson; Exp. 399; JRSO/IODP

The pathway to life may have started with hydrogen from a deep-sea vent. It created small organic compounds by mixing with carbon dioxide and water. More reactions led to longer organic acids and then amino acids, according to Lang. Eventually, the first microbes formed.

The research team is focused on the early steps in the process. “We are looking for the presence of a lot of these small organic molecules that we would expect are those first steps,” Lang said.

It’s still the early stages of the search for these molecules, but the researchers published their early results about the mantle’s chemical makeup in the journal Science.