Ch 29: Historical Geology

About This Chapter

Study important material on fossils and how they can help us understand geologic history by watching and reading our lessons. Track your progress with self-assessment quizzes so you can be prepared to recall important science topics.

Historical Geology- Chapter Summary

Use the video and text lessons in this chapter to brush up on your understanding of fossils, including distinguishing characteristics and how scientists estimate a fossil's age. Learn what fossils can show us about changes in our planet over time. The subjects you'll study in this chapter include:

  • Principles of uniformitarianism
  • Types of fossils
  • Definition of relative age
  • Index fossils and fossil dating
  • The fossil record
  • How fossil evidence can demonstrate changes in the Earth's environment

The lessons in this chapter are taught by professional instructors who took great care in designing lessons that are brief, but informative. If you ever find yourself struggling through a lesson or if you want to ask a question, our instructors are here to help you with anything you need before you move forward.

7 Lessons in Chapter 29: Historical Geology
Test your knowledge with a 30-question chapter practice test
Uniformitarianism: Definition, Principles & Examples

1. Uniformitarianism: Definition, Principles & Examples

Uniformitarianism is an important concept in geology that addresses the consistent behavior of geological processes over time. Learn about the concept and significance of uniformitarianism in this lesson, and then test your knowledge with a quiz.

What is Relative Age? - Definition & Effect

2. What is Relative Age? - Definition & Effect

How do geologists determine the age of different rock layers or fossils without the aid of modern equipment? Learn how geologists use rock layers to determine relative ages.

Relative Dating with Fossils: Index Fossils as Indicators of Time

3. Relative Dating with Fossils: Index Fossils as Indicators of Time

You may already know how to date a fossil with a rock. But did you know that we can also date a rock with a fossil? Watch this video to find out how we use index fossils to establish the relative ages of rocks.

Law of Superposition: Definition & Concept

4. Law of Superposition: Definition & Concept

Superposition is one of the fundamental principles of stratigraphy. It is also a statement of the obvious (or seems to be). You will learn all about the concept in this lesson.

Fossil: Definition, Types, Characteristics & Examples

5. Fossil: Definition, Types, Characteristics & Examples

Fossils provide scientists with many clues about Earth's history, offering evidence of dinosaurs and strange plants that existed in the past. This lesson will define a fossil, look at different types and characteristics of fossils, and then describe how fossils are formed.

Fossil Record: Definition & Examples

6. Fossil Record: Definition & Examples

This lesson teaches you about the fossil record. It explains how scientists learn about Earth's distant past and highlights what fossils can tell scientists about ourselves and other organisms.

Using Fossil Evidence to Evaluate Changes in Environment & Life Conditions

7. Using Fossil Evidence to Evaluate Changes in Environment & Life Conditions

How can something that died tens of millions of years ago help people in the present day understand the past? In the case of fossils, these long-dead specimens can be perfect clues for figuring out changes in environment and life conditions.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
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Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
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