CK12 Earth Science

radioactive atoms and 96.875% daughter atoms, you can assume that the substance is 5 years old. The decay of radioactive materia ...

measuring the proportion of radioactive carbon-14 to stable carbon-12. As a substance ages, the relative amount of carbon-14 dec ...

Figure 11.26: Zircon crystal. ( 15 ) In general, radiometric dating works best for igneous rocks and is not very useful for dete ...

their daughter products are used to determine the age of rocks and organic remains. Review Questions What four techniques are u ...

way in the past. Why is it important to assume that the rate of radioactive decay has remained constant over time? Further Readi ...

tree ring Layer of wood in a tree that forms in one year. You can determine the age of a tree by counting its rings. varve Thin ...

(9) Hermann Wiese. Outcrop. GNU-FDL. (10) Kurt Rosenkrantz.. CC-BY-SA. (11) Kurt Rosenkrantz.Fossils. CC-BY-SA. (12) Fossil shel ...

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Chapter 12 Earth’s History 12.1 Geologic Time Scale In this Earth’s history chapter, you will learn about some of the ways that ...

Earth to learn two main things: theorderin which events happened on Earth, andhow longit took for those events to happen. For ex ...

tall mountains may have once been low, flat ground. These kinds of changes take place over many millions of years, but they are ...

Figure 12.1: The Geologic Time Scale. ( 15 ) ...

OneofthefirstscientiststounderstandgeologictimewasJamesHutton. Inthelate1700s, he traveled around Great Britain and studied sedi ...

Review Questions How old is the Earth? Why did early geologic time scales not include the number of years ago that events happe ...

12.2 Early Earth Lesson Objectives Describe how the Earth formed with other parts of the solar system more than 4 billion years ...

12.3). Huge mountains have formed, been destroyed, and replaced with new mountains. The oceans have opened up and moved around t ...

What is the atmosphere and what is it made of? How do weathering and erosion affect the Earth? Formation of Earth and Our Solar ...

Figure 12.6: An artist’s rendition of a baby star still surrounded by a protoplanetary disc in which planets are forming. ( 10 ) ...

Figure 12.7: The surface of the moon is scarred by collisions with debris that was meters to kilometers in diameter. Most of the ...

Figure 12.8: The surface of Mercury shows similar collisional cratering. Most of the plan- etesimals were accreted into planets ...