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Along the Ring of Fire
1 Off the coast of Alaska, molten rock rises through cracks in the floor of the Pacific Ocean. This superheated material known as magma oozes like toothpaste squeezed from a tube. Stretching, grumbling, and erupting, the earth slowly builds a new island.
2 Along the Pacific coast of South America, one part of the planet’s surface gradually drifts toward another. Although difficult to believe, the rocky outer crust of Earth is not solid; rather, it is broken up into gigantic pieces called plates. Up to 250 miles thick, the plates, which float on top of a softer layer of hot rock, move at a pace of 0.39 to 3.94 inches per year. As the plates slide past one another, the action can sometimes result in volcanic activity.
3 These dramatic events take place thousands of miles apart, yet they are connected. Surrounding the Pacific Ocean is a circle of volcanoes that includes more than half of the world’s active volcanoes. While many are sleeping giants, others ooze lava and toss ash and rock into the air. This region is called the Ring of Fire.
4 The Ring of Fire stretches from the west coast of South America northward to Alaska. It curves left at the Aleutian Islands and crosses the Pacific Ocean. Then it heads down the east coast of Asia toward New Zealand. Historical Eruptions
5 Major volcanic eruptions along the Ring of Fire make history. In 1883 Krakatoa, an island volcano at the western edge of the ring, erupted in four explosions. The third explosion was so loud that it could be clearly heard 3,000 miles away. Krakatoa heaved a massive dust cloud nearly 50 miles into the air. For a year, that cloud shrouded Earth and changed the weather worldwide.
6 Closer to home, Mount St. Helens, a volcano in the Cascade Range in Washington, erupted in 1980. Although Mount St. Helens did not spew lava, it did cause tremendous damage. This eruption hurled a cloud of superheated ash, dirt, rock, and gases into the air. The ash blew eastward and was thick enough to disrupt travel. The side of the mountain fell away, causing a landslide.
7 In 1991 Mount Pinatubo in the Philippines erupted after 600 quiet years. During four days in June, Pinatubo released more than 20 million tons of debris into the air, destroying many homes. Asia Australia Pacific Ocean South America America North Ring of Fire 13
8 Some volcanoes erupt more quietly, with lava oozing through the cracks in Earth’s surface. This type of volcano is found in Hawaii. Fluid lava from a volcano, such as Kilauea, tends to advance slowly but still causes extensive damage. Deep beneath the surface of the ocean, the Ring of Fire is destructive, but it is constructive too. How can a volcano destroy and build at the same time? How Volcanoes Can Be Helpful
9 After a volcano erupts, lava flows and then hardens into rock. More lava adds another layer to the rock. Eventually the rock builds into either a mountain or an island. Many years must pass before the harsh surface of the new island can sustain life. Over time the hard volcanic rock crumbles into soil. Wind carries seeds that fall into the soil and take root. Islands soon become covered with dense plant life. Flowers and fruits attract birds, insects, and other animals.
10 Island chains like Japan, New Zealand, and Hawaii formed as a result of volcanic activity. Mount Fuji in Japan is one of these volcanoes, though it is not an active one. It is said to be a dormant, or sleeping, volcano for the time being. Part of a national park, it has not been active in hundreds of years. Farmers even plant crops in fields along the slopes of Mount Fuji.
11 The Ring of Fire is constructive in other ways too. Its activity not only forms islands, it also provides useful materials. Volcanic rock contains reserves of minerals commonly used in everyday life. Large deposits of aluminum, nickel, zinc, and copper are found in volcanic rock all over the world. A form of aluminum appears on grocery store shelves as foil and cans. Nickel, zinc, and copper have dozens of uses, including the copper wire and pipes found in most homes.
12 Volcanic activity creates some of the most spectacular fireworks found in nature. True, destruction lies behind the fireworks, but eventually new life will rise from the ruins. If the Ring of Fire seems distant and unreal, remember that it also exists as an island awaiting new life, as a field for growing food, and as part of the pipes that make a home.
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