Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 5: Problem 4

How do we know that Earth was once entirely molten?

Short Answer

Expert verified
Answer: The three main pieces of evidence suggesting Earth was once entirely molten are the density differences between Earth's layers, Earth's magnetic field, and the process of differentiation.

Step by step solution

01

Evidence 1: Density Differences Between Earth's Layers

One indication that Earth was once molten comes from the density differences between its layers. The Earth is composed of a solid inner core, a liquid outer core, a solid mantle, and a thin solid crust. The densest materials, such as iron and nickel, can be found in the Earth's core, while lighter elements like oxygen, silicon, and aluminum are concentrated in the crust. This implies that denser elements must have once been distributed throughout a molten Earth, allowing them to sink and concentrate in the core.
02

Evidence 2: Earth's Magnetic Field

Another piece of evidence suggesting that Earth was once molten is the existence of its magnetic field. Earth's magnetic field is mainly generated by the motion of the liquid outer core, which conducts electricity. If the Earth was never molten, it would not have a liquid outer core, and the generation of the magnetic field would be unexplained.
03

Evidence 3: The Process of Differentiation

The process of differentiation also supports the idea that Earth was once molten. Differentiation is the process through which heavier elements sink to the center of a planet, while lighter elements rise to the surface. This process is essential in the formation of Earth's layers. In order for differentiation to occur, the entire planet must have been in a molten state, allowing the elements to separate based on their densities. In conclusion, the density differences between Earth's layers, Earth's magnetic field, and the process of differentiation all provide evidence that our planet was once entirely molten.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Ozone and carbon dioxide each make up only a fraction of a percent of our atmosphere. Why, then, should we be concerned about small increases or decreases in the atmospheric abundance of these gases?

Describe the process of plate tectonics. Give specific examples of geographic features created by plate tectonics.

What is the difference between ozone depletion and global warming?

How does the greenhouse effect influence the temperature of the atmosphere? Which properties of greenhouse gases in the atmosphere cause this effect?

What are the differences among igneous, sedimentary, and metamorphic rocks? What do these rocks tell us about the sites at which they are found?
See all solutions

Recommended explanations on Physics Textbooks

Physical Quantities And Units

Read Explanation

Electricity and Magnetism

Read Explanation

Turning Points in Physics

Read Explanation

Astrophysics

Read Explanation

Further Mechanics and Thermal Physics

Read Explanation

Electricity

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free