Chapter 10 Smartworks Activity Answers

1. Which of the following correctly describe the Earth during the Hadean Eon? a. Its interior was so hot that a solid outer crust, if present at all, was likely being extensively remelted, The crust was mostly ultramafic magma and rock, and the atmosphere was dominated by volcanically emitted gases, Temperatures were likely too hot to sustain a liquid ocean. 2. Place the following ages in order from oldest to youngest. a. (oldest to youngest) age of the Earth, age of the moon, age of the oldest minerals on the Earth, age of the oldest rocks on the Earth 3. Sort the examples of global change based on whether they are unidirectional, cyclic (nonperiodic), or cyclic (periodic). a. Unidirectional: evolution, differentiation of Earth’s layers b. Cyclic (Nonperiodic): plate tectonics, mass extinctions c. Cyclic (Periodic): Earth’s axial tilt, ice ages 4. What evidence do geologists use to identify a meteorite impact as the cause of the extinction of the dinosaurs? a. Glass spheres, a large crater in the Yucatan Peninsula, shocked quartz, a layer of iridium in several areas around the globe 5. Place the events that led to the formation of the first ocean in order from youngest to oldest. a. (youngest to oldest) Rain fills basins to create oceans, water condenses in the atmosphere, Earth cools, Continental crust forms, Late heavy bombardment ends 6. This image shows the way that North America might have looked 90 million years ago, during the Late Cretaceous. Label the diagram with the tectonic features listed. a. 7. Rank the order of occurrences during the first 2 billion years of the Earth’s history. a. (oldest to youngest) earliest evidence of liquid water, oldest rock sample, first chemical signature of life, first cratons, oldest undisputed fossils 8. Which major climatic and biologic events happened during the Pleistocene Epoch? a. There were numerous extinctions of large animals toward the end of a glaciation, Much of the northern hemisphere experienced an ice age 9. Rank the order in which these organisms evolved. a. (first to last) Fish, Land plants, Amphibians, Reptiles, Mammals 10. This video discusses how glacial deposits support the theory that Antarctica and North America were once connected. Think back to the Proterozoic Eon and the supercontinent named Rodinia. a. South America, Antarctica, Australia 11. Rank the order in which the earliest organisms evolved. a. (oldest to youngest) archaea and bacteria, protists, fungi and shellless invertebrates, green algae, shelled invertebrates 12. Rocks and fossils are the primary tools geologists use to study the Earth’s history. What is each best used for? a. Rocks: numerical ages of geologic events, previous tectonic configurations b. Fossils: evolution, extinction events 13. How did the Cambrian explosion of life change the nature of the living world? a. Many defensive structures and behaviors were favored in natural selection due to the proliferation of carnivores, Numerous filter feeders and deposit feeders and large, mobile predators complicated the world food web 14. Many scientists have proposed a new geologic interval known as the Anthropocene, which is marked by distinct human-caused changes. Which of the following are items that might mark the beginning of the Anthropocene for a geologist 1,000 years in the future? a. pollutants such as cesium and plutonium in the rock record, extinction of many of Earth's species, trace fossils such as concrete and glass 15. What are some of the causes of mass extinction events? a. large igneous province eruptions, climate change, asteroid impact, tectonic activity 16. Identify North America's geologic provinces by dragging the labels to the indicated regions. a.