Earth's Tectonic Plates

4. The process here the collision between two plates collide and one gets forced under
5. The theory that the earth has plates that move across the surface
7. A system that maps the seafloor by sending sound beams and measuring the echo time
8. The solid, innermost layer of Earth, composed primarily of iron and nickel
9. A tectonic belt of volcanoes and earthquakes surrounding the Pacific Ocean
13. A natural tube formed by flowing lava and after eruptions, is left as an empty tunnel
14. The rigid, outermost layer of Earth, composed of the crust and the solid, uppermost part of the mantle
18. A supercontinent that existed approximately 335 to 175 million years ago, when all the Earth's landmasses together
19. An elastic wave in the earth produced by an earthquake or other means
20. A group of ideas and models supported by large amounts of evidence

1. A zone in the Earth's upper mantle, located below the rigid lithosphere, that behaves as a viscous, semi-fluid layer
2. Requirements for any engineering solutions success
3. A hill like figure with an opening in a planet's crust where hot liquid rock, ash, and gas escape from inside
6. The hypothesis that continents have slowly drifted away from what used to be one landmass
10. Wegener had one of these about The Continental Drift
11. The hard, outermost layer of the earth
12. The process where rocks on the sides of ridges pull and magma comes up, cool, and causes new seafloors
15. A sudden and violent shaking of the ground, as a result of movements within the earth's crust and plates
16. The limitations on an engineering solution
17. This is a break in the earth's crust