Eruptions! written by Pam Holden Teacher Talk "Do you know that the deep core of the Earth contains boiling melted rock called magma? Find out how it sometimes explodes through the Earth's crust as lava, forming a volcano. There are several kinds of volcanoes to learn about. Can you think of anything good about a volcano?” Key Words collect Earth island measure power study thrown world Teaching Plan • Use Teacher Talk to stimulate discussion of topic. Eruptions! Contents Page • Develop research skills based on this subject. • Refer to Table of Contents to locate subject matter. • Understand use of quotation marks: “hot spots” • Identify adverbs and adjectives used to enhance text. • Read dates written as numbers: 1983 1980 • Research foreign locations referred to in text. • Use Glossary to clarify terms used in text. • Refer to Index to locate specific information. • Promote drama, writing or art as follow-up activities. Word Count = 839 What is a volcano? Types of volcanoes Active volcano sites Eruptions on land Volcanologists Submarine volcanoes Witness a volcano Dormant volcanoes Extinct volcanoes Looking at volcanoes Index 2 4-7 8-9 10 12 14 16 18 20 22 24 First published in 2011 by Red Rocket Readers, an imprint of Flying Start Books Ltd. 88a Hinemoa Street, Birkenhead, Auckland, New Zealand. story © Pam Holden ISBN 978-1-877506-72-7 Printed in New Zealand All photographs supplied by Thinkstock.com This book is copyright. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without permission in writing from the publisher. www.redrocketreaders.com written by Pam Holden 1 sudden volcanic eruption A volcano is a mountain that has built up around an opening in the Earth’s surface. The core of the Earth contains hot melted rock, called magma, which sometimes bursts through the Earth’s crust as lava, pouring out of the mountaintop with steaming mud, gases, smoke and ash. It can happen suddenly as pressure gradually builds up inside until it explodes, or erupts. 2 3 cone-shaped volcano Mt. Fuji in Japan • Active or live volcanoes may erupt suddenly without any warning. • Dormant volcanoes, which are sleeping, show signs of life, so might erupt again at some unknown time in the future. • Extinct volcanoes have stopped erupting and are dead, so they are absolutely safe. Most volcanoes are shaped like cones, but some are wide and flat, and some are under the sea or on islands. There are three types of volcanoes: alive, sleeping and dead. 4 5 The Ring of Fire Active volcanoes are alive and ready to explode at any time. Whether an eruption is short or long, large or small, fierce or gentle, noisy or quiet, it can be extremely dangerous! Encircling the edge of the Pacific Ocean is a huge horseshoe shape called “The Ring of Fire”. It is the home of more than 75 of the world’s active and dormant volcanoes. Other places with active volcanoes are called “hot spots”. 6 7 eruption at Mt Kilauea in Hawaii Many other countries have active volcanoes, including: • Japan • Canada • Philippines • Sicily • Iceland • Costa Rica • Nicaragua • USA • Indonesia The most active volcano on Earth is Mount Kilauea in Hawaii, which has been erupting continuously since 1983. Red-hot lava pours into the sea constantly, making a spectacular sight, especially when observed at night from a ship! 8 9 incredible damage An eruption on land brings great danger to humans and animals. Boiling lava flowing down a mountainside can reach farms, towns and forests, destroying lives as well as buildings and vegetation. Whole towns and villages have been buried in several parts of the world, like Pompeii in Italy. Volcanic ash floating in the air is a serious danger to aircraft, as it limits visibility. It can also be sucked into jet engines, blocking them to a standstill. 10 11 volcanologist We need special scientists called volcanologists who are trained to check volcanoes, so that they can warn people whenever there is likely to be an eruption. For safety on visits to observe volcanoes, volcanologists wear protective clothing and work with special equipment to measure volcanic activity. They collect samples of rock, lava and ash to study, so that more can be learnt about volcanic action. 12 13 volcanic coastline in Hawaii When we hear the word submarine, we usually think of a ship that travels under the water. But there are many submarine volcanoes that erupt on the sea floor. Boiling magma can push an underwater mountain’s cone up to the ocean surface, where it forms a new island. Lava pours into the sea making the water steam and hiss. The islands of Hawaii were formed from huge submarine volcanoes about a million years ago The world’s largest volcano is Mauna Loa, which rises 5 miles (almost 9 kilometres) from the ocean floor in Hawaii. 14 15 erupting volcano A mountain blowing its top is an amazing sight! If we were unfortunately close to an erupting volcano, we would see red-hot lava pouring out of the mountain and streaming quickly down the mountainside. We would feel enormous heat, hear deafening roaring noises, and smell the suffocating black smoke of the burning mountainside. We would be choking on the ash flying out of the fire as we ran at full speed to save our lives. Even being a witness to a volcanic eruption from a safe distance must be a terrifying experience! 16 17 Mt St Helens crater exploding A volcano that is not erupting is called dormant, which means “sleeping”. It may be quiet for many years before awakening with an eruption that can be gentle or sudden, sometimes exploding violently without any warning, causing widespread damage and loss of human lives. Mount St Helens in Washington State, USA, erupted in 1980 after being dormant for more than 120 years. 18 19 crater lake 20 Many volcanoes are extinct, which means that they are dead. They have stopped erupting and are safe, with absolutely no signs of life. Volcanologists’ tests show that they will probably never erupt again. There are several useful things about old volcanoes. At the top of a volcano is a hollow called a crater, which sometimes becomes a lake or grassy valley. Valuable gems have been found nearby, and miners have discovered copper, gold and silver there. The old lava thrown out years before becomes fertile soil for the growth of new plants for farming. Volcanic rock is useful to construct buildings, bridges and roads. 21 active volcano Volcanoes are known to exist on other planets such as Mars and Venus, as well as on our moon. Active volcanoes are popular tourist attractions, being visited at a safe distance by people wanting to see the amazing sight of lava streaming from an erupting mountain. With the help of volcanologists checking carefully and giving warning of trouble, we can learn more about the wonder and power of volcanoes. 22 23 Index active Glossary 6, 8 active working, moving dangers 10 crater a wide hole in the ground dormant 6, 18 dormant asleep, resting erupt explode, blow its top extinct dead, finished erupting fertile good for growing crops lava hot melted rock erupting extinct 20 Hawaii 8, 14 lava 2, 10, 14, 16, 20, 22 magma 2, 14 planets 22 magma hot melted rock inside Earth submarine 14 submarine under the sea volcanologists 24 Page 12-13 volcano a mountain that erupts volcanologist a scientist for volcanoes witness person who watches an event Advanced Fluency 1 Non-Fiction Set A GUIDED READING O R/R DRA INTERVENTION LEVEL 24 ISBN 978-1-877419-31-7 24
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