Learn on PengiAmplify Science (California) Grade 7Chapter 3: Investigating the Rate of Plate Movement

Lesson 1: Rate of Motion

Key Idea.

Section 1

The Imperceptible Creep

Key Idea

To a human observer, the ground feels stationary. However, tectonic plates are continuously creeping across the planet's surface.

The rate of this motion is incredibly slow, averaging only a few centimeters per year—roughly the speed at which fingernails grow. Because this change is so gradual, it takes millions of years for continents to move noticeable distances.

Section 2

GPS Technology Evidence

Key Idea

Since humans cannot feel this slow motion, scientists rely on technology. The Global Positioning System (GPS) allows for precise measurements of Earth's surface.

By placing GPS receivers on different plates and tracking their positions over years, scientists obtain hard data. This GPS evidence proves that the plates are indeed moving and allows us to calculate exactly how fast and in what direction they are traveling.

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Chapter 3: Investigating the Rate of Plate Movement

  1. Lesson 1Current

    Lesson 1: Rate of Motion

  2. Lesson 2

    Lesson 2: Historical Evidence (Wegener)

  3. Lesson 3

    Lesson 3: Deep Time and Pangea

Lesson overview

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Section 1

The Imperceptible Creep

Key Idea

To a human observer, the ground feels stationary. However, tectonic plates are continuously creeping across the planet's surface.

The rate of this motion is incredibly slow, averaging only a few centimeters per year—roughly the speed at which fingernails grow. Because this change is so gradual, it takes millions of years for continents to move noticeable distances.

Section 2

GPS Technology Evidence

Key Idea

Since humans cannot feel this slow motion, scientists rely on technology. The Global Positioning System (GPS) allows for precise measurements of Earth's surface.

By placing GPS receivers on different plates and tracking their positions over years, scientists obtain hard data. This GPS evidence proves that the plates are indeed moving and allows us to calculate exactly how fast and in what direction they are traveling.

Book overview

Jump across lessons in the current chapter without opening the full course modal.

Continue this chapter

Chapter 3: Investigating the Rate of Plate Movement

  1. Lesson 1Current

    Lesson 1: Rate of Motion

  2. Lesson 2

    Lesson 2: Historical Evidence (Wegener)

  3. Lesson 3

    Lesson 3: Deep Time and Pangea