E-Book Overview
Written for an introductory one-semester geology course, this text is a brief version of Thompson/Turk's MODERN PHYSICAL GEOLOGY. Thompson/Turk's brief text offers professors a more streamlined alternative to the longer, more detailed introductory text. INTRODUCTION TO PHYSICAL GEOLOGY emphasizes human-environment interactions and discusses the latest research in physical geology. Beautiful illustrations and clear writing style set this text apart from other geology texts.
E-Book Content
C H A P T E R
1 Geology and the Ear th
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magine walking on a rocky shore. You can see the pounding surf, hear stones clink together as waves recede, feel the wind blowing in your hair. But the cliffs don’t move and the ground doesn’t shake. Even though the Earth appears to be a firm foundation beneath your feet, it is a dynamic planet. Continents slowly shift position; mountains rise and then erode away. These motions escape casual observation because they are generally slow, although every year events such as volcanic eruptions and earthquakes remind us that geologic change can be rapid.
A storm-driven wave crashes against the Oregon coast. (H. Richard Johnston/Tony Stone Images)
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CHAPTER 1
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1.1 THE SCIENCE OF GEOLOGY
GEOLOGY AND THE EARTH
Geology is the study of the Earth, including the materials that it is made of, the physical and chemical changes that occur on its surface and in its interior, and the history of the planet and its life forms.
THE EARTH AND ITS MATERIALS The Earth’s radius is about 6370 kilometers, nearly one and a half times the distance from New York to Los Angeles (Fig. 1–1). If you could drive a magical vehicle from the center of the Earth to the surface at 100 kilometers per hour, the journey would take more than two and a half days. Most of the Earth is c