Rocks, Plates, and Human Impact

3. plate boundary where two plates move toward each other, often forming folded mountains, volcanoes, or undersea trenches
4. process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary.
8. a dense sphere of solid iron and nickel at the center of Earth
9. a descriptive scientific statement or equation that reliably predicts events without explaining them
11. rigid layer made up of the uppermost part of the mantle and the crust.
15. plate boundary where two plates move past each other in opposite directions; tends to cause earthquakes
17. process by which fertile land becomes dry and arid as a result of drought or deforestation
19. a type of rock that forms from an existing rock that is changed by heat, pressure, or chemical reactions.
21. well-tested explanation that unifies a broad range of observations
23. soft layer of the mantle on which the tectonic plates move
24. a type of rock that forms when particles from other rocks or the remains of plants and animals are pressed and cemented together
25. a type of rock that forms from the cooling of molten rock at or below the surface
26. the strong, lower part of the mantle directly outside the outer core
27. a testable prediction, often implied by a theory

1. a layer of molten iron and nickel deep inside earth
2. the concept that earth's continents have moved across the earth's surface through geological time.
5. the transition of land from being natural or rural to being developed
6. an undersea mountain chain where new ocean floor is produced; a divergent plate boundary, further driving plates apart
7. processes by which previously broken-down particles of rock, sand, and soil are carried away
10. the breaking down of rocks and other materials on the Earth's surface.
12. process by which molten material adds new oceanic crust to the ocean floor at a divergent boundary
13. a current caused by the rising of heated mantle material and sinking of cooled mantle material that moves tectonic plates
14. the removal of trees faster than forests can replace themselves.
16. steep-sided depressions that form when the roof of an underground limesotne cave collapses
18. plate boundary where two plates move away from each other., often forming mid-ocean ridges or rift vallies
20. molten rock beneath the earth's surface
22. theory explaining the structure earth and many associated phenomena as resulting from the interaction of contiental plates that are in constant motion