Plate Tectonics study guide answers.docx

### **Plate Tectonics Study Guide** ### **Structure of the Earth** 1. 2. 3. ### **Historical Context of Earth\'s Layers** 4. Seismic waves 5. Continental fit, fossils, mountains, earthquakes 6. 250 million years ago Pangea supercontinent: all continents were attached and slowly mo...

### **Plate Tectonics Study Guide** ### **Structure of the Earth** 1. 2. 3. ### **Historical Context of Earth\'s Layers** 4. Seismic waves 5. Continental fit, fossils, mountains, earthquakes 6. 250 million years ago Pangea supercontinent: all continents were attached and slowly moved apart over millions of years. He noticed coastlines of Africa and South America fit together, and evidence of same plant and animal fossils were found along coastlines of both continents. Mountain ranges on these continents also matched up 7. 8. ### **Evidence Supporting Plate Tectonics** 9. a. b. c. d. e. f. ### **Modern Understanding of Plate Tectonics** 10. 11. 12. **Overview of Crust Types** =========================== ### **Continental vs. Oceanic Crust (compare and contrast)** 13. 14. Continental over 4 billion years old and oceanic crust is only 200 million years old 15. **oceanic crust is denser, that\'s why it is subducted under continental** **Tectonic Plate Boundaries** ============================= ### **Types of Plate Boundaries and what they cause** 16. 17. Plates move together: creates trenches when ocean subducts continental, tsunamis from earthquakes, island arcs from oceanic subducting oceanic, and mountains when continentals collide together 18. ### **Convergent Boundaries** 19. **oceanic/oceanic: older oceanic subducts under newer oceanic plates creating island arcs** **oceanic/continental: oceanic subducts under continental forming trenches and volcanoes on continent** **continental/continental: two continental plates collide and buckle up forming mountains** 20. Subduction zones lead to: island arcs, trenches, and volcanoes 21. Example of volcanic arcs: mariana islands and aleutian islands ### **Mountain Formation** 22. 23. Himalayas: mount everest What is happening to this mountain every year and why? Growing nearly an inch each year because the plates are still moving towards each other **Geological Phenomena Associated with Plate Movement** ======================================================= ### **Volcanic Activity** 24. Effusive and explosive Why are the eruptions different? Pressure, Rate of degassing and viscosity of magma. High levels of these lead to explosive eruptions. 25. Danger to communities ### **Earthquakes and Tsunamis** 26. Caused by large underwater earthquakes 27. Asian Tsunami, which killed more than 200,000 people in 11 countries across the Indian Ocean region in December 2004. **Importance of Understanding Plate Boundaries** ================================================ ### **Human Impact and Safety (Know the following:)** - - - - -.