Lesson 1.1: The Long Beginning

There are various outcroppings of rock and trenches around the world. These features indicate that Earth’s crust is not solid but instead is composed of a number of rigid plates that move and slide up over their edges. In this lesson you will describe the interior structure of Earth and analyze how movement within Earth creates crustal movement.

• Read pages 296 to 299 of the textbook. Answer the questions as you encounter them.

Check your answers with those in the “Practice Answers” in the online course.

Way below the ground you stand on, convection currents provide the driving force behind the movement and shifting of Earth’s crust. These convection currents are invisible to you. In the next activity you will study convection currents in an aquarium. This activity will provide you with more insight into the motion of Earth’s mantle.

 

• Read pages 300 and 301 of the textbook, starting at “Dynamic Crust” and ending at “1.1 Summary”. Answer the questions as you encounter them.

Check your answers with those in the “Practice Answers” in the online course.

• Read “1.1 Summary” on page 301 of the textbook. Then complete “1.1 Questions”.

Check your answers with those in the “Practice Answers” in the online course.

---

Go to Assignment 1.1: The Long Beginning.