photo credit: Wikipedia
By Kira Krall:
People know about volcanoes. How can you not remember the 2010 Eyjafjallajökull eruption?
But only about 20% of volcanic eruptions occur on land. The other 80%? They happen in deep, deep oceans.
In 2009, the deepest recorded underwater eruption happened 4,000 feet below the waves. For some perspective, recreational SCUBA divers are limited to about 130 feet. At 3,300 feet down, absolutely no sunlight can be seen.
Underwater volcanoes expel magma just like land volcanoes do. As the magma cools, it forms a hard surface. As the volcano repeatedly erupts, the magma begins to layer. Eventually, the cooled magma breaches the surface of the water. This is how islands are formed!
Hydrothermal vents are like the underwater volcano’s little sibling. They don’t explode magma in earth-shaking eruptions, but they do play an important role in the Earth’s seismic activity.
These vents do exactly what their name implies. They expel water that’s been heated as a result of magma activity. “Heated” is an understatement. The water coming out of these vents can reach temperatures up to 867° fahrenheit. That’s a pretty big deal considering the water surrounding the vents is about 35° fahrenheit.
For a while, scientists thought these vents had zero biological activity; then in 1977, they found Pompeii worms.
They can grow up to 8 feet long and don’t require any sunlight. They convert the toxic hydrogen sulfide that’s coming out of the vents into food. Crabs, shellfish, and bacteria can also be found in this biological community.
To date, less than 5% of the ocean has been explored. Considering that the ocean makes up about 70% of the Earth’s surface, there’s quite a bit more to discover. And I have a good feeling that everything we find will be just as mind-blowing as underwater volcanoes and super-heated worms.