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About Underwater Volcanoes

Mauna Kea is Hawaii's and the world's tallest peak. It measures 47,000 ft from the base of the volcano to the summit. Underwater volcanoes account for up to 75 percent of annual magma output; they eventually form into islands. Underwater volcanoes erupt differently than surface volcanoes. Most underwater volcanoes are hidden at an average of 8,500 ft. These volcanoes could form a new island. They are also called "submarine volcanoes". Most are located at mid-ocean ridges where Earth's tectonic plates are spreading apart. They're found deep underwater, but there are some in shallower water. An underwater volcano erupts a little differently than a surface volcano. There is an unlimited amount of water to cool down the lava. A shell of rock hardens around the lava almost instantly, creating a type of formation called pillow lava.

Damages of Underwater Volcanoes

Underwater volcanoes can cause earthquakes up to 2,000 miles away. You might not feel the earthquake but the earthquake can cause damage. They can cause ocean pollution that may cause problems for fishermen. There are organisms that get harmed by the gases or chemicals in the underwater volcano. The aquatic animals could be killed if they were next to the volcano when it erupts. If a person was on a boat over the underwater volcano and it erupted they would die.

History of Underwater Volcanoes

There are about 20,000 underwater volcanoes in the Pacific. Ten eruptions have been caught on video. 80% of volcanic eruptions happen underwater. The underwater volcanic eruption near Tonga created a new island. More than 5,000 active underwater volcanoes have been discovered. Kick 'em Jenny is the name of an active underwater volcano in the Caribbean Sea, which is about 8 km north of Grenada. Between 1939, the volcano’s first recorded eruption, and 2001, its last, it is said that there were 12 more eruptions. Today, there is a 5-km safety zone around the volcano to deter adventurous snorkelers and scuba divers.

How Submarine Volcanoes Form New Islands

Molten volcanic material is pushed out from the submarine volcano and results in the formation of a large mass of material if the plate pauses for a sufficient length of time at the spot. In this way, a volcanic island, or ridge, is built. The plate moves, and the other part of it lies over a hot spot, receiving new volcanic material. Afterward the older material, if it's become an island, is introduced to erosion and is then worn down.

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Extra Information

If the 4,000 volcanoes per million square kilometers on the floor of the Pacific Ocean is estimated for all the oceans than there are more than a million submarine volcanoes. Maybe as many as 75,000 of these volcanoes rise over half a mile above the ocean floor. Technology and hard work by a group of explorers and geologists have allowed us our first detailed look of submarine volcanoes. Many others lie at such great depths that the tremendous weight of the water above them results in high, confining pressure and prevents the formation and release of steam and gases. Even very large, deep water eruptions may not disturb the ocean floor.

Resources

http://pubs.usgs.gov/gip/volc/submarine.html
http://www.crystalinks.com/volcanoesunderwater.html
http://en.wikipedia.org/wiki/Submarine_volcano
http://www.universetoday.com/guide-to-space/earth/underwater-volcanoes/