Lesson 1.4: Getting a Handle on Time

Looking at a distinctive feature of Earth’s surface, such as the contrasting layers of land running along a riverbank, you may think that a series of unusual events led to its formation. Your thinking would be consistent with early theories of geological processes, which emphasized sudden, violent events. The modern theories of geological processes emphasize slow and weak processes that have occurred over time spans of millions of years. This lesson will provide you with a better understanding of these immensely long time spans.

• Read page 314 of the textbook.

In the next activity you may use your imagination to tell an eventful story behind the formation of some distinctive features of Alberta’s landscape.

• Read pages 315 and 316 of the textbook, starting at “How Much Time ?” Answer the questions as you encounter them.
  
  Check your answers with those in the “Practice Answers” in the online course.

Rocks may seem so permanent to you. But over the long term they do undergo change. In the next activity you will see the nature of this change.

 

• Read “The Rock Cycle” and “The Rise of Uniformitarianism” on page 317 of the textbook.

The next investigation helps to clear up a mystery about contrasting layers along the banks of the Athabasca River.

• Read “1.4 Summary” on page 318 of the textbook. Then, complete “1.4 Questions”.
  
  Check your answers with those in the “Practice Answers” in the online course.

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Go to Assignment 1.4: Getting a Handle on Time.