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Learn about radiocarbon dating, fossil succession, and geological history in this study guide. Explore how radiocarbon dating works, the principle of fossil succession, and key events in Earth's history such as the Mesozoic and Cenozoic eras.
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Warm-up Week 18 • Radiocarbon dating could be used to date which of the following? a. 65 MYA meteorite c. 60,000 YA metamorphic rock b. 15 MYA lava flow d. 60,000 YA tiger bone • The principle of fossilsuccession states that different types of fossil organisms ____. a. succeed one another in a certain order b. generally leave behind hard parts c. are younger in the deepest layers of rock • occur most often in sedimentary rock • ________ most likely contributed to the extinction of large mammals in the late cenozoic era. a. Deadly reptile predators c. A shortage of food b. The evolution of humans d. The break-up of pangaea
Q: How old is Earth? ~4.56 Billion Yrs! Q: How do you know?
Uniformitarianism • Forces and processes we see today have been working thesame wayformany years. Q: What are some processes? Past Present
Law of Superposition YOUNGER ↑ OLDER ↓
Principle of Cross-Cutting Relationships • Anything that divides a layer is younger
Which type of plant was dominant during the Cenozoic? • Which type of organism was characteristic of the Precambrian?
Study Guide… • 25 Minutes. • Review. • Game.
Review #2 Stromatolite = Algae!
Becoming a Fossil… • _____ Burial. • _____ Parts. • Shells, bones FAST HARD
Principle of Fossil Succession • Same order or creation • Index Fossils • Widespread • A___ of rocks GE
Radioactive Decay • Isotopes Stable atoms • “Half-Life” • Time for ½ of nucleus stable.
Q: What fraction is left after 4 half-lives? Q: 1/8 of a sample is left. The half-life is 8 years. How old is the sample?
Radiometric Dating • Calculate “birthdate” • Radiocarbon Dating • Living things • Ratio of Carbon • “Death” date.
Precambrian History • ___% of Earth’s History • Earth Forms • Early A__________ Evolves 88 TMOSPHERE • Evidence: • R________ • F________ OCKS OSSILS
Great Paleozoic Extinction. • Continents moved together • C_______ changed quickly • Bye Bye Organisms. LIMATE
Mesozoic Life: • Mesozoic Extinction • M________ ETEOR
Q: What caused the extinction at the end of Paleozoic? Pangaea Change in Climate Q: What caused extinction at end of Mesozoic? Meteor.
Late Cenozoic Mammal Extinction HUMANS HUNTING!