6.2+Plate+Tectonics+.pptx

HMH Science Dimensions Earth and Space Science Unit 6: Plate Tectonics Lesson 2: Tectonic Plates Unit 6 Lesson 2 Motion of Earth’s Surface • The San Andreas Fault, like other faults, is a break in rock along which the rock can slide. • Faults show that parts of Earth’s surface move relative to ot...

HMH Science Dimensions Earth and Space Science Unit 6: Plate Tectonics Lesson 2: Tectonic Plates Unit 6 Lesson 2 Motion of Earth’s Surface • The San Andreas Fault, like other faults, is a break in rock along which the rock can slide. • Faults show that parts of Earth’s surface move relative to other parts 2 Unit 6 Lesson 2 Can You Explain It? The lithosphere on the western side of the fault is moving northwest relative to the lithosphere on the eastern side of the fault. The San Andreas is a complex fault system that marks a major boundary in Earth’s lithosphere. 3 Unit 6 Lesson 2 Motion of Earth’s Surface This map shows the motion of the lithosphere as velocity vectors—arrows that represent speed and direction. 4 Unit 6 Lesson 2 Motion of Earth’s Surface • Scientists measure the shaking to determine the precise location of an earthquake’s epicenter, the point on Earth’s surface above the earthquake’s starting point, or focus . Earthquakes from a period of 40 years. Active volcanoes in past 10,000 years ANALYZE What do you observe about the patterns of earthquakes and volcanoes? 5 Unit 6 Lesson 2 Motion of Earth’s Surface ANALYZE Compare the patterns of ground motion, earthquakes, and volcanic eruptions shown on the maps. Describe the patterns and how they seem to relate to each other. Use specific examples to support your claim. 6 Unit 6 Lesson 2 Motion of Earth’s Surface Earth’s outer layer, its lithosphere, is divided into distinct pieces known as tectonic plates 7 Unit 6 Lesson 2 Earth’s Lithospheric Plates Continental and Oceanic Crust EXPLAIN Compare sections from the different parts of the South American plate. How are they similar? How are they different? What do the sections tell you about what the crust is made of and how it formed? 8 Unit 6 Lesson 2 Earth’s Lithospheric Plates The Composition of the Crust • The composition and structure of the crust reflect the processes that shape plates. The South American plate is typical of many plates composed of both continental and oceanic crust. • 9 Unit 6 Lesson 2 Earth’s Lithospheric Plates • Continental crust and oceanic crust transitions within the continental margin, which includes the continental shelf and nearby sediment. • A non-obvious transition is called the continent-ocean boundary 10 Unit 6 Lesson 2 Continue Your Exploration Choose one of the paths below to continue your exploration: • Relative and Absolute Plate Motion • Sampling Oceanic Crust • Eggshell Tectonics 11