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Notes 3.2

 * magma chamber -** a chamber that holds the magma
 * pipe -** tubes that connects the magma to the surface
 * vent -** a opening on the volcano
 * lava flow -** the part that is covered with lava as it flows out of the vent
 * crater -** a bowl shaped part on top of the volcano that collects magma
 * silica -** silica is a element that is formed by oxygen and silicon
 * pahoehoe -** a lava that flows vary fast, when cooled it shapes like ropes
 * aa -** a lava that flows very slow, when cooled it forms blocks
 * pyroclastic flow -** an explosion of gases, "bombs", ash, cinders, and rocks
 * active -** a volcano that can erupt in the future
 * dormant -** a volcano that is "asleep"
 * extinct -** a volcano that is "dead"
 * hot spring -** a stream of water that shoot up at a certain time
 * geyser -** a water fountain that erupts from the ground
 * geothermal energy -** heat energy made by heated (by magma) steam or water

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Outline
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Introduction

 * Hawaii's goddess, Pele
 * Pele is the destroyer and creator of the Hawaiian island
 * Pele lives under active volcanoes
 * If Pele is mad, she shoots out lava

How Magma Reaches Earth's Surface

 * magma rises
 * because magma is less dense than the solid material, magma can flow through the cracks
 * the magma rises until it reaches the surface
 * a volcano erupts
 * When a volcano erupts, it is like carbon dioxide released from soda
 * When a volcano eruption happens, the gasses in the magma flows out carrying the magma with them

Inside a Volcano

 * the magma comes from a pocket called a magma chamber
 * in order to let magma travel reach the surface, the magma travels through the pipe
 * the point when the magma gets out the pipe is called the vent
 * the magma then is collected in a bowl-shaped area on top of the volcano called the crater
 * the magma that reaches the top is called lava
 * the stream of lava that flows to land is called lava flow

Characteristics of Magma

 * some magma flows very slowly, because it is very thick
 * some flows almost as fast as water, because it is very thin
 * the hotter the magma, the the faster it flows
 * some magma are so sticky that it won't flow very far
 * some magma produces dark colored lava

Types of Volcanic Eruptions

 * quiet eruptions
 * runny lava flows quietly out of the crater
 * quiet eruptions form two different types of lava
 * pahoehoe
 * pahoehoe is a fast-moving lava
 * when cooled, forms wrinkles, "rope", and billows
 * aa
 * when aa is cooled, it forms bumpy rocks
 * explosive eruptions
 * the explosion sends out gases, "bombs", ash, cinders, and rocks

Stages of a Volcano

 * there are three kinds of volcano
 * active
 * a volcano that can erupt in the future
 * dormant
 * a volcano that is "sleeping"
 * extinct
 * a volcano that won't erupt

Other Types of Volcanic Eruption

 * there are two other different kinds of volcanic eruption
 * hot spring
 * a hot spring is a pool of water formed by heated ground water seeping through the earth
 * geyser
 * a fountain heated by magma

Monitoring Volcanoes

 * geologists monitor volcanoes by:
 * they use tiltmeter, laser-ranging device, and other devices to level the slight movement
 * they take temperatures from ground water, so they can see if the magma is getting hotter

Volcano Hazards

 * people live near Mount St. Helens got careless and forgot about it, until it woke up from its 123-years sleep
 * both quiet and explosive eruptions are dangerous
 * quiet eruptions bury citys, sets fire, and cause difficult breathing
 * volcanic ash can bury citys, clog car engins, and damage crop
 * if the ash is wet itis badd day for you! Damp ash can collaps roofs