Tectonic Plates

5. the outermost shell of a terrestrial planet.
6. scientific study of the deformation of the rocks that make up the Earth's crust and the forces that produce such deformation.
8. long narrow depressions on the sea floor
9. a continuous range of underwater volcanoes that wraps around the globe like seams on a baseball, stretching nearly 65,000 kilometers
11. he sideways and downward movement of the edge of a plate of the earth's crust into the mantle beneath another plate.
12. a seafloor mountain system formed by plate tectonics

1. when 2 plates move away from each other.
2. a portion of the Earth's mantle that flows like molten plastic despite being solid.
3. The linear boundary between two diverging lithospheric plates on the ocean floor.
4. a fracture or zone of fractures between two blocks of rock.
7. when 2 plates come together.
10. a theory explaining the structure of earths crust