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Ring of Fire and Volcano Facts
Many people have one image of a volcano in their head: a big mountain spewing lava. But where does the lava come from, and why does it happen in the first place? Also, there are plenty of other volcanoes that spew gas or ash, so not all volcanoes fit that one image in our minds. Use some of these resources to learn more about what a volcano is and how they impact us today.
What Are Volcanoes?
A volcano is typically a mountain or hill with an opening where rock, gas, hot vapor, or lava erupts from the earth's crust. Volcanoes can come in many shapes and sizes. They are typically classified in five different ways: cinder cones, composite cones, calderas, flood basalts, or shield volcanoes. A shield volcano looks much less like the volcanoes we seen in cartoons and movies. It typically looks more like a hill, with long, gentle slopes (looking more like a shield on its side). On the other hand, composite cones are tall, like ordinary mountains, and are more likely to explode in large eruptions of gas and ash. Famous volcanoes like Mount St. Helens and Mount Vesuvius are in this category.
How Are Volcanoes Formed?
Believe it or not, the earth beneath our feet is moving and shifting all of the time. Rather than being one solid thing, the crust of the earth shifts on top of the earth's mantle, a layer of super-hot liquid metals. Like sponges floating on top of water, these plates move, slide, and bump into one another. We don't feel it all of the time because it's happening on such a big scale. This concept is called plate tectonics. When bits of crust, or plates, bump into each other, sometimes it causes earthquakes, but at other times it can cause volcanoes. Super-hot lava from the mantle of the earth bubbles up to the surface at soft points of the crust or certain places where the plates meet. Over thousands of years, pressure builds under the surface.
What Causes a Volcano to Erupt?
After those thousands of years, what causes them to finally explode? Sometimes, an earthquake creates an opening in the crust, but more often, gas bubbles inside simply increase the pressure until finally the volcano erupts. Eruptions can be explosive or non-explosive, with or without intense gases, and some have a lot of ash, while others can lead to less ash. These eruptions can happen frequently and with few bad consequences, but sometimes they happen only once every few thousand years, with major problems for humans as a result.
Volcanoes are all around the world, and they can be very, very dangerous. However, we don't need to always be scared of them. Many volcanoes are dormant, or in other words, they haven't erupted in 10,000 years. Those that are active, or have erupted since the last ice age, are typically monitored by scientists. It should be something that we're aware of but not constantly fearful of.
The Ring of Fire
After learning about plate tectonics, students may hear a lot about "the Ring of Fire." It's a term to describe one large region around the Pacific Ocean. It's fairly active, as the plate that it's on seems to move and grind against other plates on a more regular basis. Due to that movement, which is relatively quicker than that of other plates, the area experiences a lot of earthquakes, tsunamis (or dangerously large waves), and volcanoes. Hawaii and Japan are home to some of the most famous volcanoes.
All in all, volcanoes are fun to study. Today, you can find volcanoes across the world, from Japan to Alaska to Italy. Many volcanoes are safe, and many are constantly monitored. Some of them are so constantly monitored that you can watch live videos on a regular basis. Check out some of these webcams to watch volcanoes in action (or dormancy).
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