Processes that Shape the Earth

6. boundary,A plate boundary where two plates move away from each other.
8. map,A map that shows the surface features of an area.
9. plate,a piece of the lithosphere that moves around on top of the asthenosphere
11. by which rock, sand, and soil are broken down and carried away (i.e. weathering, glaciation)
12. weathering,The process in which rock is broken down by changes in its chemical makeup
13. interval,the difference in elevation from one contour line to the next
15. drift,The hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations
16. description of surface features of land.
18. line,A line on a topographic map that connects points of equal elevation
20. breaking down of rocks and other materials on the Earth's surface.
21. soft layer of the mantle on which the lithosphere floats.

1. boundary,A plate boundary where two plates move toward each other.
2. plate going under another plate
3. difference in elevation between the highest and lowest parts of an area
4. contour,on a map, a darker, heavier contour line that is usually every fifth line and that indicates a change in elevation
5. weathering,Any process that breaks rock down into smaller pieces without changing the chemistry of the rock; typically wind and water.
7. rigid layer made up of the uppermost part of the mantle and the crust.
10. in which sediment is laid down in new locations.
14. boundary,A plate boundary where two plates move past each other in opposite directions
16. hypothesis that has been tested with a significant amount of data
17. tectonics,The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle.
19. spreading,the formation of new areas of oceanic crust, which occurs through the upwelling of magma at midocean ridges and its subsequent outward movement on either side.