20 Fascinating & Fun Science Facts: Volcanoes
How much do you know about volcanoes? Test your knowledge with these fascinating facts.
- A volcano is an opening in the Earth’s surface from which magma, gas, and ash can erupt and escape.
- The word volcano originates from the name of the Roman god of fire, ‘vulcan’.
- Volcanoes are most commonly found on tectonic plate boundaries. Tectonic plates are pieces of the Earth’s surface that fit together like a jigsaw.
- Volcanoes are also found over mantle plumes which are very hot areas of rock inside the Earth.
- Volcanoes are not just found on the Earth’s surface. There are many more volcanoes on the ocean floor than on land, in fact, ¾ of all volcanoes are underwater. There are even volcanoes under ice caps as can be found in Iceland.
- The Ring of Fire is a 40,000km horseshoe-shaped area in the Pacific Ocean and is home to 90% of all volcanoes on Earth.
- Volcanoes form on either destructive plate boundaries or constructive plate boundaries. On a constructive plate boundary, also called a divergent plate margin, plates move apart. A volcano is formed as magma wells up to fill the gap and forms a new crust.
- On destructive plate boundaries, also called convergent, an oceanic and continental plate move together. The denser oceanic plate is forced under the lighter continental plate and this friction causes the oceanic plate to melt. Magma rises up through the cracks and erupts onto the surface.
- Volcanoes are classified as active, dormant, or extinct. Active volcanoes experience regular activity, dormant means there hasn’t been recent activity but it may still erupt, and extinct indicates that the volcano is inactive and it is highly unlikely to ever erupt again.
- Volcanoes can be a variety of shapes and sizes, depending on the type, amount, and thickness of lava that erupts and the way it erupts. Shield volcanoes are flat and large, composite volcanoes are tall and steep, cinder cones are oval-shaped with a deep mound, and calderas are big and round like a cauldron.
- Magma is hot liquid rock inside a volcano. Once magma leaves the volcano and erupts to the surface it is called lava.
- Lava can reach temperatures as hot as 1,250℃. Lava may spurt up if there is pressure or simply flow out of the vent. The hotter and thinner the lava, the farther it will flow. When it stops flowing it hardens into rock called igneous rock.
- Approximately 1,900 volcanoes on Earth are active and likely to erupt.
- 350 million people in the world live within the danger range of an active volcano.
- Soil near volcanoes is rich and fertile due to the volcanic ash that settles there. Because of this, many choose to farm on the land on and near volcanoes.
- At 4,169m tall, the world’s largest active volcano is Mauna Loa in Hawaii.
- In 79 A.D, Mount Vesuvius erupted and devastated the town on Pompeii in Italy. The ash preserved the town and the remains of the people in it.
- In 1883, Krakatoa in Southeast Asia erupted. It released 200 megatons of energy, which is equivalent to 15,000 nuclear bombs. It is the loudest sound ever reported in history.
- Large eruptions can block the sun’s radiation and drop temperatures on Earth. In 1991, Mount Pinatubo in the Philippines ejected sulphur dioxide which formed a haze of sulphuric acid. This prevented the normal amount of sunlight from reaching Earth and lowered global temperatures by 0.5℃.
- Volcanoes can trigger tsunamis, floods, earthquakes, pyroclastic flow, mudflows, lava flows, ash, avalanches, and poisonous gas. They can cause a lot of damage and destroy buildings, kill and injure people, destroy forests, ruin crops, cause illness, and poison lakes and rivers.
Want to learn more about volcanoes and earth science? For more science, more amazing facts, and more fun, enrol now in our science holiday camps and science classes where kids can learn, experiment, explore, and play!