Hydrothermal Venting

Assembled from 23 blocks · 3 evidence · 8 related

1. Story
2. Seawater percolating into fractured young oceanic crust is heated by underlying magma, leaches metals and sulphides, and returns to the seafloor as hot, chemically reduced fluid. First observed directly at the Galapagos Rift in February 1977. The chemistry matters more than the heat: chemosynthetic bacteria oxidise reduced compounds such as hydrogen sulphide in the vent fluid and turn that energy into biomass, supporting dense animal communities. This was the first known ecosystem on Earth whose base is not photosynthesis. Venting is a process, not a place - it occurs wherever the right geology exists along mid-ocean ridges, back-arc basins and seamounts.
3. Knowledge
4. Hydrothermal Venting
5. Giant Tube Worm (Riftia pachyptila)
6. Galapagos Rift
7. Connections
8. Galapagos Rift
9. Giant Tube Worm (Riftia pachyptila)
10. Alvin finds hydrothermal vents on the Galapagos Rift
11. Submarine thermal springs on the Galapagos Rift published in Science
12. Chemoautotrophic symbionts identified in Riftia pachyptila
13. Hydrothermal Venting
14. Alvin finds hydrothermal vents on the Galapagos Rift
15. Submarine thermal springs on the Galapagos Rift published in Science
16. Hydrothermal Venting
17. Bathypelagic Zone (Midnight Zone)
18. Alvin finds hydrothermal vents on the Galapagos Rift
19. Chemoautotrophic symbionts identified in Riftia pachyptila
20. Evidence
21. Direct submersible observation in February 1977 documented hydrothermal venting on the Galapagos Rift and dense associated animal communities including clams, mussels and large tube worms, in permanent darkness.
22. Riftia pachyptila houses sulphur-oxidising chemoautotrophic bacteria in the trophosome; the adult worm lacks a mouth and functional gut and depends on carbon fixed by these symbionts.
23. The Galapagos Hydrothermal Expedition, funded by the US National Science Foundation, sailed on R/V Knorr from 8 February 1977; Alvin dives revealed vent communities of giant clams, mussels and metre-long tube worms - the first known ecosystem not based on photosynthesis.