Restless Earth

5. new oceanic crust is formed as tectonic plates pull apart and magma rises
7. rock formed when lava or magma cools and hardens
8. formed at plate boundaries usually when plates collide
12. the semi-liquid layer of the mantle where convection currents happen
13. cycles: hot material rises, cool materials sink; drives plate tectonics
15. extinction events that occur over a long time period
18. name of the ancient supercontinent when it was all one landmass
19. formed as a result of high temperature and pressure deep within Earth changing a rock that already existed
20. a group of the same species living in the same area
21. located between the mantle and outer core

1. instruments used to measure and record seismic waves
2. sudden events that led to a mass extinction
3. forms after weathering and erosion when sediments compact and cement
4. tectonic plates move away from each other usually forms new crust and rift valleys
6. large rigid pieces of the Earth's lithosphere that move and interact with each other along plate boundaries
9. fractures or zones of weakness in the Earth's crust
10. includes the crust and upper part of the mantle; is divided into tectonic plates
11. tectonic plates move toward each other usually forming mountains and volcanoes
14. an opening in the Earth's crust through which molten rock is pushed out and creates new rock
16. where tectonic plates slide past each other, causing earthquakes
17. deep elongated depressions in the ocean, often associated with subduction zones