The Galápagos Rift hydrothermal expedition

Jack Corliss and the Alvin team · 1977 CE · Earth

The Galápagos Rift hydrothermal expedition — Jack Corliss and the Alvin team · 1977 CE · Earth — Recorded expedition route · schematic map

Dive on the temperature anomalies found the year before and prove that hot water circulates through the ridge.

Historical context

Heat-flow measurements said the mid-ocean ridges were losing heat that conduction could not account for, and Corliss's analyses of ridge basalts said seawater was circulating through the hot rock; by the early 1970s hot springs on the sea floor were predicted, but no one had seen one. In February 1977 a National Science Foundation expedition of geologists and geochemists, with no biologist aboard, took the submersible Alvin to the Galápagos Rift. On 17 February its first dive found warm, shimmering water and, around it, white clams, brown mussels and crabs; later dives found red-plumed worms in white tubes. Ballard wrote that they had discovered something new upon Earth: animals that needed no sunlight at all.

The voyage, step by step

  1. Sailing from Panama

    8 February 1977

    On 8 February 1977, by Woods Hole's account, the research ship Knorr leaves Rodman Naval Base, at the Pacific entrance of the Panama Canal, towing Lulu, the catamaran that carries the submersible Alvin, for a rift some 640 kilometres west of the coast of Ecuador.

  2. Why the ridge should be hot

    1977 CE

    On the way south-west the tow is dropped and Knorr runs ahead. The idea she carries is simple: seawater must sink into the young crust, heat up near the magma below and come back out somewhere.

  3. The camera sled goes down

    15 February 1977

    On 15 February Knorr lowers the camera sled ANGUS into the rift valley and tows it a few metres above the lava. Partway through the run, a temperature spike lasting less than three minutes marks a target.

  4. Alvin on the rift

    17 February 1977

    At sunrise on 17 February 1977, on Alvin's dive 713, pilot Jack Donnelly takes the geochemist Jack Corliss and the geologist Tjeerd van Andel down to the lava floor of the rift, about 2,500 metres below.

  5. Clambake

    1977 CE

    Around the warm cracks lie white clams up to 30 centimetres long, brown mussels, many white crabs and a purple octopus, crowded into a patch about 50 metres across on otherwise barren lava.

  6. The Garden of Eden

    1977 CE

    Later in the cruise, at a vent the geologists name the Garden of Eden, white tubes stand in thickets, each tipped with a blood-red plume, in water measured at 17 degrees.

  7. Preserved in vodka

    1977 CE

    With no biologist aboard and no preservative planned, the first vent animals go into the little formaldehyde a student had brought, then into strong Russian vodka bought in Panama, and even that runs short.

Outcome

Warm springs found at about 2,500 metres on 17 February 1977, surrounded by dense animal communities that, the expedition reported in Science in 1979, draw their energy from chemosynthesis rather than sunlight.

Jack Corliss and the Alvin team

Geochemist who went looking for hot springs on the Galápagos Rift in 1977 and found, around them, animals that live without sunlight.

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