• black smokers and 350 degrees Celsius water found (super hot)
• where first hydrothermal vents were found (1977)
• lots of benthic life: ex) tube worms 

• Dr. David A. Ross of Woods Hole
• Oceanographic institution examines a sediment core collected in the Red Sea during a 1965 expedition on board R/V Chain

1. hotter waters in the red sea

2. metal-rich sediments

3. unusual rocks

4. ophiolites

5. missing heat

• RED SEA
• found by the russians first (1880) Vitaz, temperature samples warmer than projected
• 1960s DR. DAVID ROSS saw abnormal core samples/ temperature probe indicated a warmer temperature than expected 

E2: Metal Rich Sediments 

[image]

• stratified layers by different types of metals in cores 
• indicate a chemical reaction is occurring
• usually cores are dissolved/mixed 
• the Deep Sea Drilling Project (1963-83) drilling vessel Glomar Challenger to collect cores all over the world

E3: Unusual Rocks

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• most rocks from the mid-ocean ridge are black in color, with some white and pale green crystals
• but then--scientist found mid-ocean ridge seafloor rocks with unusual shades of green, orange, and brown
• colors could only come from chemical reactions involving hot water

E4: Ophiolites

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ocean crust on land

• copper mine in Cyprus
• stratified sediments caused by heat 

E5 Missing Heat

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• Abnormal heat distribution: different from theoretical heat distribution
• difference between theoretical line/measured line
• this indicates a chemical process that is changing the temperature of ocean water 

• 1977
• Discoverer: Bob Ballard 
• a group of geologists found using alvin
• research on hydrothermal vents
• bacteria/archaea might have originated at hydrothermal vents 

• vehicle used to look for hydrothermal vents
• found whole new biosphere

hot 

oxygenated 

black minerals precipate 

variable structure (from heat) 

not as hot

silica and anhydrite precipitates

common structural organization

1. cold seawater sinks down through the cracks in the crust

2. oxygen and potassium are removed from the seawater

3. calcium, sulfate, and magnesium are removed from the fluid

4. sodium, calcium, and potassium from the surrounding crust enter the fluid

5. the fluids have reached their highest temps. copper, zinc, iron, and sulfur from the crust dissolve in the fluids

6. hot fluids carrying dissolved metals rise up through the crust

7. the hydrothermal fluids mix with cold, oxygen-rich seawater. metals and sulfur combine to form black metal-sulfide minerals. (metal sulfides come out of the hydrothermal vent which drives primary production)

• primary production w/o light
• uses chemical energy instead of solar energy
• performed by microscopic Archaea 

1977, the galapagos rift

• H2O + CO2 + H2S + O2 --> CH2O + H2SO4
• water + carbon dioxide + hydrogen sulfide + oxygen --> carbohydrates + sulfuric acid

tube worms

[image]

• plume filters oxygen, hydrogen sulfide and CO2 from seawater
• plume contains hemoglobin (that's why it's red)
• blood transports chemicals to bacteria in the cavity
• bacteria produces sugar and tube worms use some of it (symbiosis)

• dead whale hypothesis (stepping stones)
• following deep currents

• discovered in 1984
• high salinity
• normal temp
• H2S-rich water seeps
• support bacterial groups

• observed in 1984
• hydrogen sulfide and methane as energy sources
• not dependent on plate activity 

• suggested by Edward Forbes in the 19th century
• no life below 550 m
• no sunlight
• no food
• enormous pressure
• proved to be false by the challenger expedition

whale fall stage 1

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a mobile scavenger stage, lasting ~4 months to > 1.5 years

whale fall stage 2

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the opportunistic macro fauna leaves and bacteria and small invertebrates start to dominate the diversity

whale fall stage 3

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• scarce food sources: hydrothermal vents, whale fall
• high pressure
• caustic chemicals
• chemosynthesis