Facts About Volcanoes - strangefacts

• The biggest volcano in the world is the Mauna Loa, in Hawaii. It rises off of the seafloor to 13,000 feet above sea level or about 29,000 feet above the seafloor

• Most volcanoes are 10,000 to 100,000 years old

• There are at least 1,500 active volcanoes around the world

• Indonesia has the most volcanoes about more then 200 alive

• Common volcanic gases include water vapor, carbon dioxide, sulfur dioxide, hydrogen chloride, hydrogen fluoride and hydrogen sulfide

• Volcanic eruptions can send ash high into the air, over 30km (17 miles) above the Earth’s surface

• The lower 48 states in the U.S. have about 40 volcanoes

• Scientists has estimated the ocean contains 10,000 volcanoes

• The oldest volcano is the Etna at 350,000 years old

• About 500 million people live close to active volcanoes
  

• Volcanoes are openings in the Earth’s surface. When they are active they can let ash, gas and hot magma escape in sometimes violent and spectacular eruptions

• The word volcano originally comes from the name of the Roman god of fire, Vulcan

• Hot liquid rock under the Earth’s surface is known as magma, it is called lava after it comes out of a volcano

• Some famous volcanic eruptions of modern times include Mount Krakatoa in 1883, Novarupta in 1912, Mount St Helens in 1980 and Mt Pinatubo in 1991

• While we certainly have some big volcanoes here on Earth, the biggest known volcano in our solar system is actually on Mars. Its name is Olympus Mons and it measures a whooping 600km (373 miles) wide and 21km (13 miles) high

• The object with the most volcanic activity in our solar system is Io, one of Jupiter’s moons. Covered in volcanoes, its surface is constantly changing to the large amount of volcanic activity

• Most people think of volcanoes as large cone shaped mountains but that is just one type, others feature wide plateaus, fissure vents (cracks were lava emerges) and bulging dome shapes

• There are also volcanoes found on the ocean floor and even under icecaps, such as those found in Iceland

• Volcanoes can be active (regular activity), dormant (recent historical activity but now quiet) or extinct (no activity in historical times and unlikely to erupt again)

• While these terms are useful, scientists are more likely to describe volcanoes by characteristics such a how they formed, how they erupt and what their shape is?