An expedition from Woods Hole An expedition from Woods Hole Oceanographic Institution using Oceanographic Institution using ALVIN,ALVIN, discovered communities of discovered communities of animals living around deep animals living around deep hydrothermal vents off the hydrothermal vents off the Galapagos IslandsGalapagos Islands

Named – The Rose GardensNamed – The Rose Gardens

Depths of 8000 – 8500 feetDepths of 8000 – 8500 feet

What We Know TodayWhat We Know Today

Hydrothermal vent activity is known Hydrothermal vent activity is known to occur at seafloor-spreading to occur at seafloor-spreading centers worldwide. centers worldwide.

These communities are found These communities are found between 9between 9° and 21°N latitude along ° and 21°N latitude along the East Pacific Rise, N. Fiji Basin, the East Pacific Rise, N. Fiji Basin, Mid-Atlantic Ridge, and Gorda and Mid-Atlantic Ridge, and Gorda and Juan de Fuca Ridges in the NE. PacificJuan de Fuca Ridges in the NE. Pacific

High water temperatures (68 -High water temperatures (68 -752752°F)°F)

High PressureHigh Pressure High Concentrations of SulfidesHigh Concentrations of Sulfides Lack of OxygenLack of Oxygen Acidic pH LevelsAcidic pH Levels Absence of lightAbsence of light Located 100-1000 meters below Located 100-1000 meters below

surfacesurface

Geysers of heated water from Geysers of heated water from beneath the ocean surfacebeneath the ocean surface

Generally found at the mid-ocean Generally found at the mid-ocean ridges or spreading platesridges or spreading plates

Seawater seeps down through Seawater seeps down through cracks in the ridges to depths of cracks in the ridges to depths of 1.25 to 2mi1.25 to 2mi About halfway through the About halfway through the

thickness of the oceanic crustthickness of the oceanic crust

The water is super-heated to The water is super-heated to 400-450400-450°C °C (750-840(750-840°F)°F)

This superheated water then re-This superheated water then re-ascends to the center of the mid ascends to the center of the mid ocean ridge and emerges as a ocean ridge and emerges as a fast jet about 350°C. fast jet about 350°C.

As it mixes with cold ocean As it mixes with cold ocean water (34-36°C), hydrogen water (34-36°C), hydrogen sulfide precipitates instantly sulfide precipitates instantly often coloring the jet black.often coloring the jet black.

Black SmokersBlack Smokers White SmokersWhite Smokers Warm Water VentsWarm Water Vents

Hottest of all vents (+350Hottest of all vents (+350°C)°C) Emits high concentration of sulfideEmits high concentration of sulfide Hydrogen Sulfide is usually toxic to Hydrogen Sulfide is usually toxic to

life, but the specialized life, but the specialized communities around the black communities around the black smokers could not survive without smokers could not survive without itit

Forms the largest chimneysForms the largest chimneys

Cooler temperature of water Cooler temperature of water released (300released (300°c vs. 350°C)°c vs. 350°C)

Lower sulfide concentrationLower sulfide concentration Barium, calcium and silicone Barium, calcium and silicone

released forming white released forming white precipitateprecipitate

Low ion content as compared Low ion content as compared with black and white smokerswith black and white smokers

Cool water temperatures (20-Cool water temperatures (20-4040°C)°C)

Above Ground – Yellowstone Old Above Ground – Yellowstone Old FaithfulFaithful

““An oasis in the deep” An oasis in the deep” containing an astonishing containing an astonishing assemblage of benthic assemblage of benthic organismsorganisms

More than 400 different species More than 400 different species identified in vent communitiesidentified in vent communities

Fastest Growing Marine Invertebrate