Name__________________________________________ Period _________________ Date __________________ Midterm Practice QUIZ Chapter 9 1. If the Cretaceous Period began about 146 Ma, this means it began __________________________________ 2. Geologic time is divided into _____________eons. 3. Precambrian time consists of ______________________________________________ 4. A geologic period is usually named for the place where its characteristic ______________ were first discovered. 5. The gradual development of new organisms from preexisting organisms is called _________________________ 6. Which of the geologic time period’s rock is characterized by severe damage? _____________________________ 7. The division of geologic time that makes up about 88% of Earth’s history is called _________________________ 8. Scattered landmasses on Earth merged into a supercontinent during ______________________________________ 9. The Devonian Period is also known as the Age of ______________________________ 10. According to the impact hypothesis, dinosaurs became extinct when ______________________________________ 11. The Cenozoic Era is known as the Age of _______________________________ 12. The Precambrian rock record is difficult to interpret because __________________________ has altered the original order of rock layers. 13. The appearance of many new life-forms during the first period of the Paleozoic Era was probably aided by the development of __________________________________________________________________ 14. The most common Precambrian fossils are ________________________ 15. The first period of the Mesozoic Era was called the ____________________________ Period. 16. The end of the Permian Period was marked by __________________________________________ 17. What happened when temperatures decreased during the ice ages of the Cenozoic Era? _______________________ _______________________________________________________________________________________ 18. On a geologic column, the oldest rocks are located where? _____________________________________________ 19. Mountain ranges created during the Cenozoic Era include the __________________________________________ 20. Scientists have most accurately determined the absolute ages of rock layers by using _____________ dating methods. 21. A variety of life-forms appeared in the Cambrian Period due to ________________________ covering the continents. 22. What can a scientist assume about the formation of a rock layer that matches a similar layer in a geologic column? ______________________________________________________________________________________________ 23. Dinosaurs became extinct at the end of the ______________________________________ 24. Dinosaurs first appeared during the ____________________________________________ 25. You exist during the __________________________________________________________________