Ch 2: Understanding Earth's History

About This Chapter

This collection of bite-sized lessons and quizzes examines the history of the planet Earth. Access these lessons at any time to improve your Earth science knowledge, prepare for an exam or get ahead in class.

Understanding Earth's History - Chapter Summary

Work through this chapter at your own pace to better understand the history of our planet. Our expert earth science instructors explain several Earth formation and geological evolution theories as well as information pertaining to the sun's structure and the major eras of Earth's history. Each lesson comes with a short quiz, and the chapter concludes with a comprehensive exam. You can also submit questions to our instructors if you need any extra help. Upon completion of the chapter, you should be able to:

  • Evaluate theories regarding the formation of the Earth and moon
  • Outline the sun's structure
  • Differentiate between the geological evolution theories of catastrophism and uniformitarianism
  • Summarize the history of life on Earth

5 Lessons in Chapter 2: Understanding Earth's History
Test your knowledge with a 30-question chapter practice test
Formation of the Earth: Theories

1. Formation of the Earth: Theories

In this lesson, the theory of how the planet Earth formed will be discussed. This includes looking at how it differentiated into three layers, how it formed its atmosphere, water, and land features, and how it continues to evolve today.

Formation of the Moon: Theories

2. Formation of the Moon: Theories

Explore the four major theories on the formation of the Moon. The theories include the fission theory, capture theory, condensation theory and giant impact theory. Also look at both information supporting and flaws found in these theories.

Structure of the Sun

3. Structure of the Sun

Discover the layers of the sun, including the core, radiative zone, convective zone, photosphere, chromosphere, and corona. Find out which layers you can see from Earth. Investigate what sunspots and solar flares are.

Theories of Geological Evolution: Catastrophism vs Uniformitarianism

4. Theories of Geological Evolution: Catastrophism vs Uniformitarianism

Geologists haven't always agreed about the history of our planet. They have debated between catastrophism and uniformitarianism over the last few hundred years! Learn about the two main theories of geologic evolution and how scientists came to resolve the dispute.

The History of Life on Earth: Timeline and Characteristics of Major Eras

5. The History of Life on Earth: Timeline and Characteristics of Major Eras

The Earth is over 4 billion years old. Ever wonder what happened during certain time periods in that large amount of time? We will look at the major eons and eras of Earth's history along with important characteristics of each.

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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