130 likes | 218 Views
Discover how rocks, meteorites, and ancient atmospheres help reveal the solar system's and Earth's history, from dating methods to major extinctions. Explore and answer key questions in this comprehensive notebook.
E N D
The History of the Earth EQ: What techniques can scientists use to determine the age of the solar system and the earth?
ROCK DATING • Rocks allow geologists to interpret Earth’s early history • Rocks record geological events and changing life forms of the past • Half life can date rocks as billions of years old
Age of Rocks on Earth and Moon • Earth rocks about 4 billion years old • Moon rocks about 4.3 billion years old • Indicates that both are formed about the same time
Meteorites, Moon Rocks and Earth Rocks • Meteorites, moon rocks, and Earth rocks help geologists to determine the age of the solar system • Meteorites are relatively unchanged since the beginning of the solar system • Meteorites are the best source of rocks on the Earth to indicate the age of the solar system
Early Atmosphere • Started out as mostly Helium and Hydrogen • As earth cooled volcanos spewed out gases (water vapor, carbon dioxide and ammonia) • Cyanobacteria, algae, and plants used photosynthesis to convert carbon dioxide into oxygen. • Today the atmosphere is 78% nitrogen and 21% oxygen
Moon and Mercury • Atmospheres of the moon and Mercury are similar • Both have little atmospheres • Atmosphere is unable to slow down asteroids
Geological Time Scale • Helps scientists organize earth’s early events • Sequence of geological events in Earth’s history
5 Major Extinctions • End Odorvacian (86% of species lost) • Late Devonian (75% of species lost) • End Permian (96% of species lost) • End Triassic (80% of species lost) • End Creaceous (76% of species lost)
ANSWER QUESTIONS ON LEFT SIDE OF NOTEBOOK • How did oxygen become part of Earth’s early atmosphere? • What process lead to the decrease of carbon dioxide in Earth’s early atmosphere? • What are the differences between the atmosphere of the earth and that of the moon and Mercury? • What effect does an atmosphere have on the impact of asteroids?
5. Why do scientists believe that the earth and the moon were formed at the same time? 6. What types of rocks that are found on earth are the best indicator of the age of the solar system? 7. What evidence do scientists use to determine the age of the solar system? 8. How do rocks allow geologists to interpret Earth’s early history? 9. Why are meteorites good sources of information concerning the age of the solar system? 10. What is the geological time scale used for? 11. What were the five major extinctions?