Page 88 - Super Earth Encyclopedia

AT A GLANCE LOCATION On mid-ocean ridges, such as the East Pacific Rise and Mid-Atlantic Ridge DEPTH Average 6,890 ft (2,100 m) below waves SIZE A black smoker chimney may be more than 130 ft (40 m) high FORMATION Chimneys built of minerals dissolved from ocean-floor rocks GROWTH RATE A black smoker Water spurting can grow at a from the smokers rapid rate of 12 in can be as hot as (30 cm) a day. 867ºF (464ºC). VENT FIELDS The largest vent The deepest known field, known as black smokers lie TAG, is the

• • • • TEMPERATURE SUPER DEEP LIFE IN THE DARK Most animals rely on food made by plants and algae using solar energy, but black smokers erupt in the deep ocean, where there is no sunlight. The extraordinary animals living around these vents rely on food made by bacteria. While the crabs eat the bacteria, other animals such as the Pacific giant tubeworms have colonies of bacteria inside their bodies and live on the food they make.

Minerals dissolved in the hot water turn to sooty particles when they hit cold seawater. STATS AND FACTS The minerals erupted by black smokers and similar ocean-floor vents are vital to all oceanic life. VENTS FIRST FOUND 1977 ON THE EAST PACIFIC RISE Giant tubeworms gather vital minerals using their bright red gills—they have no mouth, eyes, or even a stomach.

BLISTERING HEAT

Vent water that has been superheated under pressure erupts from the chimney into ocean water that is close to freezing point. Layers of different minerals are deposited as the hot water cools in the chimney.

hot water erupt into the near-freezing darkness.
On parts of the ocean floor, jets of searingly
beneath each rift heats the ocean-floor rocks,
BLACK SMOKERS
in turn heating the seawater that has seeped
that form mid-ocean ridges. Rising magma
to dissolve minerals, which turn into dark,
They boil up from the rifts in Earth’s crust
into it. Intense pressure allows the water
smoky particles when the hot water

erupts into the cold ocean. HOTTEST WATER ON EARTH Billowing vent Water that filters down to the ocean-floor rock is heated before being forced back up into the ocean. When the erupting water mixes with the cold seawater, the minerals solidify. Some of these billow up like smoke; others build up chimneylike structures around the vents. Remarkably, the minerals also support vast colonies of specialized animals such as crabs, mussels, and giant tubeworms.

US_086-087_Black_Smokers_a_w.indd 86 02/03/17 4:55 pm