6-9+Volcanoes

A volcano is an opening in the Earth's surface or crust, which allows hot, molten rock, ash and gases to escape from deep below the surface. When pressure builds up, and the volcano is ready to explode, it releases a hot, molten, rock called magma. The temperature of the magma is very hot, about 900 degrees Farenhite. The center of the volcano is called the crater. The crater is were the lava flows out, lava also flows out through little cracks in the volcano. Volcanic activity tends to form mountains or features like mountains over a period of time.
 * Volcanoes**

Volcanoes are normally found were plate tectonics pull apart, or come together. A mid ocean ridge, like the Mid-Atlantic Ridge, has example of volcanoes pulling apart. The Pacific Ring of Fire, has examples of volcanoes coming together. When plates move apart, the plate boundary is called, a divergant plate boundary. When plates move together, that plate boundary is called a convergent plate boundary. When two plates slide past each other, the plate boundary is called a transform plate boundary.

You are probably wondering how volcanoes are formed. Well, the first step in volcano formation is magma rising from openings in Earth's crust. It then hardens and more magma rises. That magma hardens as well. this cycle repeats itself over and over until a huge volcano is formed. Volcano formation almost always takes place on plate boundaries like the ones listed above. Eventually, magma stored underneath the volcano in a magma chamber will be put under pressure. The pressure builds up and causes volcanic eruptions. Some eruptions are quiet and soft, while others are explosive and loud. Eruptions constantly build up volcanoes, change them, and add to environments.

What should you do when a volcano near you is going to erupt? Before you get all crazy, know whether you are or not at risk for danger. If you are, the first piece of advice I could give you is to stay calm! When you scream and run you won't get anything done. In an emergency like this, you need to have some things with you at all times. Some of those things are, food that will not spoil (caned food), water, flash lights, and extra batteries. Make sure you have a battery operated radio, protective clothing, dust mask, goggles and sturdy shoes. As soon as you know that there's a volcano to erupt, you should gather your family and work out a disaster plan. If you have to outside for any reason, make sure every inch of your body is covered with clothing or cloth. cover your mouth with a dust mask, or if you don't have one, a cloth. After a volcano, remember to wear your protective clothing when you're cleaning up debris.

When a volcano is about to erupt, signs are an important key. One sign is the releases of gases. Another sign is ground movement or earthquakes. Sometimes an eruption can become so violent that a landslide can occcur. Ash can also fall. Did you know in 1980 when Mount St. Helens erupted, ash was carried 22,000 square miles from the volcano? Mudflows are the worst outof all the efects a volcano has. Mudflows can reach speeds up to 20-40 mph. Mudflows act like floods, destroying houses, trees, and boulders. Even though Lahars seem thhe worst of a volcano, I think that Pyroclastic flows are the worst. Pyroclastic flows are the mixtures of ash, gas, and other volcanic material flowing down a volcano very fast. If a person is caught in a flow it's certain death. This is not an exageration. The Pyroclasticflows can't be outrunned. The flows are also hot and choking. If a volcano has a history of Pyroclastic flows, it's likely to occur soon.

Scientists can predict where and when volcanic eruptions will occur far better than any other person. They can use a seismogram to find the epicenter of an earthquake, where they can then map out any underground magma flow. This can almost lead them right to the volcano that will erupt. Scientists also test the electric magnetic field around a volcano for any changes or test the chemical composition of gas. Measuring the strength of a volcano can be done by gauging the rate of lava and gas flow. To learn more about volcano signs, you can go to these websites: [|http:/][|/vo][|lcano.und.edu/] http://www.volcanoes.com/ http://www.fema.gov/kids/volcano.htm http://www.weatherwizkids.com/volcano.htm [|olctq.htm]