In late 2000, researchers aboard the submersible Alvin observed “strange snow-white deposits of ghostly beauty” on steep cliffs of the Atlantis Massif, a massive undersea mountain near 30°N on the Mid-Atlantic Ridge.
Those carbonate chimneys, now known as the Lost City Hydrothermal Field, towered some 60–70 meters above the seafloor, unlike any vent system seen before.
This clandestine find—a forest of towering white chimneys fueled by seawater-rock reactions—has intrigued scientists ever since as a possible analog for early life’s environment on ancient Earth.
Record-Breaking Drilling
In spring 2023, the international drilling ship JOIDES Resolution set out to probe the Atlantis Massif and shattered previous depth records.
Initially targeting about 200 meters, the team unexpectedly breached almost 1,268 meters (4,160 feet) into the mantle – more than five times deeper than any drill hole before.
The cores were retrieved at a feverish pace. Microbiologist Billy Brazelton recalls, “we were smashing rocks with a sledgehammer nearly 24 hours a day,” as the 51 scientists processed samples around the clock.
This historic haul of continuous mantle rock promises unprecedented insight into Earth’s inner workings.
Ancient Systems
Lost City rests atop the Atlantis Massif, an ultramafic oceanic core complex in the North Atlantic. Radiocarbon dating of its oldest carbonates indicates these alkaline vents have been active for over 120,000 years, making Lost City far older than any known volcanic “black smoker” site.
The massif itself – a mountain in the middle of the ocean – rises nearly 4,000 meters from the abyssal plain, roughly the height of Mt. Rainier.
Tectonic extension along the Mid-Atlantic Ridge has unroofed mantle rocks here, creating a unique natural laboratory where long-lived hydrothermal circulation persists and sustains unusual ecosystems.
Growing Pressures
Today, the Lost City ecosystem faces new threats. Mining companies covet hydrothermal vents for their rich deposits of metals like gold, copper and rare earth elements.
Conservationists warn that vent communities host extreme biodiversity: new research shows about 62 % of vent-specific mollusk species are now classified as threatened, largely due to proposed mining.
Lead author Elin Thomas cautions, “mining regulation matters” – species in protected areas are doing better than those in planned mining zones.
Without swift action, deep-sea mining could destroy vents that took hundreds of millennia to evolve, wiping out endemic life with no chance to recover.
Core Sample Revelation
Expedition 399’s success is revolutionizing geology and biology. “We did it,” exults co-researcher Frieder Klein of Woods Hole Oceanographic Institution.
The continuous 1,268 m core – a volcanic window into the mantle – arrived on deck intact, yielding “a treasure trove of rocks that will let us systematically study…processes relevant to the emergence of life,” Klein told reporters.
The lead author, Johan Lissenberg, likewise notes the achievement “could reveal secrets of the planet’s history”.
Early analyses show these peridotites have far more hydrogen and methane than expected, highlighting a subsurface “chemical kitchen” where water-rock reactions fuel complex chemistry.
Mid-Ocean Context
The drill site is a tectonic crossroads. It lies on the Atlantis Massif, about 15 km west of the spreading axis at 30° N latitude, where the African and American plates diverge.
Here, the crust is thinned by normal faults, exposing deep-seated peridotite. New crust forms nearby from molten upwelling, while seawater penetrates the lifted mantle.
Lost City sits atop a secluded peak on a 1.5-million-year-old seafloor, perched above its summit chimneys at roughly 800 meters depth.
This setting of slow seafloor spreading provides the ideal laboratory to study how deep rocks and fluids interact.
Human Element
For the scientists onboard, the mission has been grueling but exhilarating. When core barrels came onboard, a weary cadre of researchers rushed to work.
BMSIS communicator William Brazelton recalls that the high-recovery drilling “had everyone working long hours” and even support staff like him had to help with processing samples.
At one point, Brazelton quipped that geology grad students smashed rocks “24 hours a day for 2 months” to keep up with the flood of material.
Their tireless effort paid off: each section of mantle rock pulled from the sea floor carries potential clues to Earth’s deep past.
Chemical Factory
At Lost City, rock meets seawater in an ongoing giant chemistry set. As Otto Brunner (OIST) explains, serpentinization reactions turn olivine-rich mantle into serpentinite, releasing hydrogen and methane.
The submerged mountain is a vast chemical factory: cold seawater seeps into cracks, reacts with peridotite, and bubbles out of white carbonate vents saturated with H₂ and CH₄. Johan Lissenberg aptly calls it a “kind of chemical kitchen” in the massif’s subsurface.
In that caustic brew – alkaline and warm – microbes feast on hydrogen, powering entire ecosystems without sunlight.
Towering Structures
The vents themselves form ghostly towers. Poseidon, the Lost City’s flagship chimney, rises about 60 meters (200 ft) high from the seafloor.
The field hosts dozens of conical carbonate mounds and chimneys – many taller than a modern 18-story building – built from precipitated calcium carbonate.
These white towers, shaped like ancient columns, continually grow as vent fluids deposit minerals. Tiny cave-like chambers and flanges in the chimneys foster thick biofilms of bacteria, which in turn nourish worms, mussels and other creatures that form a rainforest-like community under the sea. At Lost City, fragile carbonate cathedrals are home to life.
Astrobiological Connection
Discoveries here ignite imaginations beyond Earth. Astrobiologists note that if serpentinization can power life on Earth’s ocean floor, similar processes might operate in icy moons.
As University of Utah astrobiologist Sheri McGonigle observes, Lost City’s ecosystem “is based around rock and water,” suggesting that “similar environments are a good place to look for life on other planets”.
Graduate student Sheri Motamedi adds excitement: “We found microbes [in the rocks]. … If serpentinization is happening under the surface of Europa or Enceladus, we might find life there as well”. Indeed, NASA’s planned Europa Clipper mission is partly inspired by these very events.
Scientific Frustration
Abiogenesis – life from non-life – has long puzzled scientists. Lost City’s vents provide a concrete setting for resolving that enigma. The vent fluids here churn out organics abiotically. Sea water–rock reactions at Lost City produce 10–100 times more hydrogen and methane than typical vents.
As lead author Giora Proskurowski emphasizes: “The generation of hydrocarbons was the very first step, otherwise Earth would have remained lifeless”.
His team even detected simple organic acids (acetate, formate) from purely geological sources – “possible evidence in our quest to understand the origin of life”.
These findings lend weight to theories that life’s first sparks ignited in cold, alkaline vent systems like Lost City.
International Collaboration
Such a feat required a global effort. Expedition 399 brought together 51 scientists and technicians from across the world, all focused on one goal: explore Lost City and its summit rocks.
Geologists, chemists and biologists from countries on six continents sailed from Portugal to the Atlantic. From planning through drilling to lab analysis, tasks were divided internationally.
For example, cores will be archived in Bremen, Germany, but studied by teams from Japan, the UK, the USA, India and beyond. This unprecedented sample has already become a shared resource and symbol of scientific cooperation.
Strategic Recovery
The recovered cores are now curated for all to use. By expedition rules, the pristine 1.27 km suite will be stored at the IODP core repository in Bremen, Germany.
After a brief one-year moratorium on new work, the sections will be openly available to any researcher.
The Atlantis Massif core becomes a reference collection for decades. All shipboard data – geochemistry, microbiology, imaging – are likewise being released. “Open international access is an exemplary feature of IODP,” notes co-chief Andrew McCaig; the goal is to let scientists worldwide dissect the sample’s secrets.
Expert Outlook
Oceanic core complexes like Atlantis are ecological hot spots on the deep seafloor. Even though they cover only a few square kilometers in total, each OCC harbors highly specialized life.
Marine biologists warn these “small islands” can be as biodiversity-rich as tropical rainforests. Because so few OCCs have been explored, many scientists compare vent ecosystems to tropical paradises under the waves – densely populated with endemic species.
The rarity of these habitats means any loss (through mining or otherwise) is irreplaceable. Experts stress that OCCs are the planet’s rarest real estate for chemosynthetic life.
Future Implications
The mantle core findings promise paradigm shifts. By revealing how inorganic rock chemistry yields H₂, CH₄ and organics, researchers may fundamentally rewrite our origin-of-life models.
Frieder Klein notes that these processes “might have implications beyond life on Earth”.
Andrew McCaig adds that Lost City itself is a blueprint: many hypothesize that life’s first spark might have struck in a Lost City–like setting on early Earth.
This work could guide astrobiology: if life arose here from chemistry alone, then any icy ocean world with rock-water interaction becomes a potential cradle for biology.
Policy Stakes
The new insights raise urgent governance questions. Conservationists argue that regulators must act now to protect vent fields.
Policy analysts point out that damage to vents is effectively irreversible – an ecosystem millions of years in the making would not regenerate on human timescales.
OIST’s Otis Brunner highlights the urgency: their connectivity maps “could help policymakers and mining companies decide which sites should be protected from mining”. In practice,
nations are under pressure to designate marine preserves around vents. Brunner warns, because many species are endemic, destroying a vent means species-wide extinction: “if you remove or severely damage their ecosystem, … you’ve lost that species entirely”.
Global Monitoring
Around 600 hydrothermal vent fields have now been located worldwide. Most are tiny (often <0.1 km² each) and many lie in international waters. This presents a challenge: no single country can unilaterally protect or study them all.
The International Seabed Authority (ISA) oversees mineral rights in the high seas and must balance mining interests against conservation.
To date, the ISA has granted dozens of exploration contracts, but global scientists insist that precautionary management is crucial. Some vent fields already lie within marine protected areas, but the majority do not.
Increasingly, oceanographers are cataloging vent locations and advocating for a science-informed approach to stewardship.
Legal Framework
Legal experts warn deep-sea mining could clash with international law and biodiversity treaties. U.S. lawyer Duncan Currie cautions that reckless mining policies “throw out the rule book,” risking violations of the U.N. Convention on the Law of the Sea.
Environmental lawyers argue that wrecking unique deep-sea communities may breach the UN Convention on Biological Diversity’s spirit, if not its letter.
Meanwhile, newly discovered species already sit on the brink: for instance, the newly found Dracogyra “Dragon Snail” of the Cayman vent is only known from one site under an active exploration license, and is already listed as Critically Endangered.
Lead researcher Elin Thomas warns its entire genus could vanish: “the Dragon Snail is the only known member of the genus … there is a chance the entire group could go extinct”.
Cultural Shift
Lost City challenges our surface-centric view of life. It shows that some of Earth’s richest ecosystems flourish in perpetual darkness, fueled not by sunlight but by rock-derived chemistry.
As UW oceanographer Deborah Kelley notes, this research is “really important” and “lays a foundation for new understanding” of life’s possibilities.
Where biology textbooks once emphasized photosynthesis, Lost City reminds us that chemosynthesis in vents can power complex communities.
It’s a radical shift: life’s story need not begin on beaches or tides, but potentially deep beneath the sea in hidden chemical gardens.
Planetary Perspective
Ultimately, the story becomes cosmic. The Lost City discovery reframes life as a universal chemical saga: where there is rock, water and energy, life can start.
“If rock and water can give rise to living systems here,” reflects Sheri Motamedi, “we might find life [on Europa or Enceladus] as well”.
Biology may not be a sun-powered rarity but a common outcome wherever serpentinization occurs. From our vantage, Lost City expands the searchlight for life: icy ocean worlds and even other planets become prime candidates.
What began with a few white chimneys in the Atlantic now points to life as a cosmic process writ large.