Terremotos, Volcanes Y Tsunamis

Matthys Levy and Mario Salvadori

Earthquakes, Volcanoes, and Tsunamis
Projects and Principles for Beginning Geologists

Earthquakes, Volcanoes, and Tsunamis
Projects and Principles for Beginning Geologists

Matthys Levy and Mario Salvadori

Library of Congress Cataloging-in-Publication Data Levy, Matthys. [Earthquake games] Earthquakes, volcanoes, and tsunamis : projects andprinciples for beginning geologists / Matthys Levy and Mario Salvadori. p. cm. Includes index. Originally published: Earthquake games. New York : M.K. McElderry Books, c1997. ISBN 978-1-55652-801-9 1. Earthquakes—Juvenile literature. 2. Volcanoes—Juvenile literature. 3. Educational games—Juvenile literature. I. Salvadori, Mario, 19071997. II. Levy, Matthys. Earthquake games. III. Title. QE521.3.L486 2009551.2—dc22 2008040143

Cover and interior design: Scott Rattray Interior illustration: Christina C. Blatt Cover photos: iStock © 1997, 2009 by Matthys Levy and Mario Salvadori All rights reserved First published in 1997 by Margaret K. McElderry Books as Earthquake Games This edition published by Chicago Review Press, Incorporated 814 North Franklin Street Chicago, Illinois 60610 ISBN978-1-55652-801-9 Printed in the United States of America 5 4 3 2 1

To the children of P.S. 45 in the Bronx, New York, who fi st asked, “Mario, how do earthquakes work?” And to Nicola, Okna, Shae, Edison, Austin, Daniel, and Maia M. L. and M. S.

Contents

Preface vii 1. The Secrets of the Earth 1
The Cracked Egg Scraping Plates Falling Towers 7 9 12 4

The Birth of Mountains

2. If You HadBeen There
Liquefaction 20

17

3. When the Ocean Rolls 25
Convection 26 27 30 Generating a Tsunami Tsunami in a Tub

4. Earthquake Messages 35
Pressure Waves Shear Waves 38 40 41 37

The Speed of Waves Wave Reflection

Wave Refraction

42 43

The Strength of Water

5. How Strong Was It? 45
Build a Seismometer A Pendulum 51 54 56 47

Another Pendulum Experiment The Seismograph6. From Myth to Science 65
The Shaking Experiment Making Predictions Mapping the Risk 70 74 66

7. Can Animals Predict Earthquakes? 79 8. Should We Fight or Fool the Quakes? 83
A Push-Pull Demonstration A Bending Demonstration Isolation 92 93 95 Building on Pads 86 88

A Pendulum Isolator

9. The Smoking Mountains 103
A Spewing Volcano 105 108 110 Another Volcanic Eruption Build aCardboard Volcano A Smoking Volcano Geothermal Energy 112 117

Conclusion 121 Appendix: Important Earthquakes, Volcanoes, and Tsunamis 123 Resources 131 Index 133

Preface

e expect many things to move, but not the earth! How could the earth, which is strong enough to support a skyscraper, shake and break up? Where do earthquakes come from? Are we ever going to know when and where they willhit? And co uld w e e ver l earn to b uild str uctures capa ble of withstanding earthquakes? Many years have passed since humans fi st experienced earthquakes. Over time, we have learned answers to most of these questions—but not all of them. The book is b uilt around projects, demonstrations, and simple experiments that make it easy and fun to develop a physical understanding of earthquakes andtheir natural relatives—volcanic eruptions and tsunami waves. You will enjoy working on most of these projects alone or with a friend; for a few, you may want to ask a parent or an older sibling or friend to help you. In either case, you will have a good time and also learn a lot about earthquakes, volcanoes, and tsunamis.

W

vii

viii

PREFACE

We hope you will enjo y reading this book asmuch as w e did writing it, but above all, we hope that you will never meet face-toface with an earthquake, an erupting volcano, or a tsunami. NOTE: Although English units of measurement (feet, pounds, etc.) are still commonly used in the United States, almost all the other countries in the world have adopted a measurement system called the metric system or SI. This system is taught in o ur...