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Homework # 4 Relative Dating Section: Name: Date: 1. the Cross Homework # 4 Relative Dating Section: Name: Date: 1. The cross section below represents a portion of 5. The sequence of rock types found in the walls Earth's crust. Letters A through D are locations of the Grand Canyon are shown. The names within the rock units. of rock formations are shown and the upper and lower boundaries of each formation are indicated by dashed lines. The rock layers have not been overturned. At which location is quartzite most likely found? The sequence of rock layers in the cross section A. A B. B C. C D. D provides evidence that the Muave formation is A. younger than the Temple Butte, but older than the Bright Angel B. younger than both the Temple Butte and 2. Base your answer(s) to the following question(s) the Bright Angel on the geologic cross section below, which shows rock units 1 through 7 that have not been C. older than the Temple Butte, but younger overturned. Some of the rock units contain than the Bright Angel New York State index fossils. An unconformity exists between rock units 5 and 6. D. older than both the Temple Butte and the Bright Angel Key Basalt Volcanic ash Contact metamorphism 6. The geologic cross section below shows bedrock layers A through D. Line XY is a fault. What evidence shown in the cross section indicates that the basalt rock unit is the youngest rock unit? 3. Bedrock from which entire geologic time period is missing between rock units 5 and 6? The fault most likely occurred after A. all bedrock layers were formed B. layer C formed, but before layer D formed 4. Identify one metamorphic rock that could have been formed by the contact metamorphism C. layer A formed, but before layer B formed within rock unit 1. D. layer B formed, but before layer C formed page 1 7. Base your answer(s) to the following question(s) 10. The cross section of the bedrock layers of a on the cross section below. Rock units are canyon is represented below. Letters A and B labeled 1 through 8. The line between A and represent rock layers on the sides of the canyon. A' indicates an unconformity. Layer A can best be correlated to layer B by comparing the A. sediments on each side of the stream B. sequence of rock layers on each side of the canyon Which event occurred sometime after the C. organisms currently living in rock layers A formation of the unconformity? and B D. rate of erosion of rock layers A and B by A. formation of rock unit 3 the stream B. tilting of rock unit 5 C. deposition of the sediments that formed rock unit 8 D. intrusion of rock unit 7 11. Base your answer(s) to the following question(s) on the block diagram below, which shows 8. Which characteristic of the granite intrusion 0 provides the most evidence that it solidified bedrock units A through F and boundary XX . deep underground? A. very hard B. coarse texture C. light color D. felsic composition 9. Earth has sedimentary bedrock of marine origin that is four billion years old. Which inference The rock that formed in the contact can be made from this information? metamorphic zone between rock unit E and rock unit D is A. Earth had oceans four billion years ago. A. hornfels B. marble B. Sedimentary rocks formed from magma when Earth cooled four billion years ago. C. schist D. anthracite coal C. Most sedimentary rocks are at least four billion years old. D. Life existed on Earth four billion years ago. Section: page 2 Homework # 4 Relative Dating 12. Base your answer(s) to the following question(s) 16. Base your answer(s) to the following question(s) on the geologic cross section of bedrock shown on the geologic cross section below. Location A below. A through G identify rock layers and Q is within the metamorphic rock. represents a fault. Lines W, X, Y, and Z are locations of unconformities. The rocks have not been overturned. Which rock is the youngest? A. shale B. sandstone C. igneous rock D. rock at location A Which rock or feature is oldest? 17. Base your answer(s) to the following question(s) on the cross section below and on your knowledge of Earth science. The cross section A. rock A B. rock G represents rock units that have not been overturned. Lines CC0 and GG0 represent C. fault Q D. unconformity Z unconformities. The geologic ages of some of the lettered rock units are shown below the cross section. 13. The movement of bedrock along fault Q most probably produced A. gaps in the rock record B. an earthquake C. a volcanic lava flow D. zones of contact metamorphism 14. The unconformities shown in the cross section represent The diagrams below represent three index A. buried erosional surfaces fossils found in one of the rock units. B. locations of index fossils C. volcanic ash deposits D. boundaries between oceanic and continental crust These fossils are most likely found in A. rock unit I B. rock unit J 15. Identify two processes that produced the unconformity. C. rock unit K D. rock unit M Section: page 3 Homework # 4 Relative Dating 18. Base your answer(s) to the following question(s) 21. The cross section below represents four on the geologic cross section below in which different rock units. The symbol for contact overturning has not occurred. Letters A metamorphism has been omitted from the cross through H represent rock layers. section. Which two letters represent bedrock of the The sequence below represents the relative ages same age? of the rock units from oldest to youngest. limestone ! granite ! shale ! sandstone A. A and E B. B and D Which cross section below represents where the F G D H C. and D. and symbol for contact metamorphism would be located, based on the relative age sequence? A. 19. The diagram below represents three bedrock outcrops. The layers have not been overturned. Letters A through E identify different rock layers. Fossils found in the rock layers are shown. B. C. Which fossil could be classified as an index fossil? A. B. C. D. D. 20. Which scientific principle states that younger rock layers are generally deposited on top of older rock layers? a. superposition b. evolution c. original horizontality d. includsion Section: page 4 Homework # 4 Relative Dating Problem-Attic format version 4.4.274 _c 2011–2016 EducAide Software Licensed for use by Wanda Vargas Terms of Use at www.problem-attic.com Section: Homework # 4 Relative Dating 09/28/2016 1. Answer: C 2. Answer: Basalt cuts across all other rock units. / Contact metamorphism is shown between the basalt and all rock layers. 3. Answer: Ordovician Period. 4. Answer: marble or hornfels 5. Answer: C 6. Answer: D 7. Answer: A 8. Answer: B 9. Answer: A 10. Answer: B 11. Answer: A 12. Answer: B 13. Answer: B 14. Answer: A 15. Answer: 16. Answer: A 17. Answer: C 18. Answer: D 19. Answer: C 20. Answer: a. 21. Answer: A.
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