Earth’s Layers: Changing Earth homework #1 Student Name: ___________________ Use this text and the work om class to answer the questions about the Earth’s layers. Scientists know more about Earth’s crust than they do about the mantle or core. e crust is the thin, brittle outer shell of the planet. It is made of solid rock. e crust under the oceans is called oceanic crust. e crust of the continents is called continental crust. e two parts of the crust have several differences. • Oceanic crust is made of basalt, an igneous rock. It formed when lava flowed onto the ocean floor and hardened into rock. e oceanic crust is denser than the continental crust but thinner, ranging from 5 to 12 kilometers in thickness. ick layers of mud cover much of the ocean floor. • Continental crust is made of all three types of rock: sedimentary, igneous, and metamorphic. It is less dense than oceanic crust, so it rises higher above the mantle than oceanic crust. Continental crust is much thicker than oceanic crust, averaging 35 kilometers in thickness. 1. Describe Earth’s crust. 2. Why do you think scientists know more about Earth’s crust than Earth’s other layers? 3. Compare and contrast oceanic crust and continental crust. Match each definition with the correct term. nitions _____ 1. rock from space that strikes Earth _____ 2. Earth’s middle layer _____ 3. bendable layer of Earth in the upper mantle that lies beneath the lithosphere _____ 4. Earth’s outer layer _____ 5. brittle layer of Earth consisting of the crust and uppermost mantle _____ 6. liquid part of Earth’s dense metallic center _____ 7. solid part of Earth’s dense metallic center Terms a. crust b. asthenosphere c. outer core d. mantle e. meteorite f. lithosphere g. inner core Both Continental Crust Oceanic Crust