Earthquakes

3. The depth of an earthquake hypo-center.
7. Relatively hard, solid rock that commonly underlies softer rock, sediment, or soil.
8. A mathematical device to compare the size of the earthquakes.
9. The outer solid part of the earth, including the crust and uppermost mantle.
13. A seismic body wave that shakes the ground back and forth in the same direction and the opposite direction as the direction the wave is moving.
14. The point within the earth where an earthquake rupture starts.
15. A seismic body wave that shakes the ground back and forth perpendicular to the direction the wave is moving.
16. The zone of earthquakes surrounding the Pacific Ocean.
17. A number that characterizes the relative size of an earthquake.
18. A fracture along which the blocks of crust on either side have moved relative to one another parallel to the fracture.

1. The outermost major layer of the earth.
2. The distance between successive points of equal amplitude and phase on a wave.
4. The ductile part of the earth just below the lithosphere, including the upper mantle.
5. Earthquakes that follow the largest shock of an earthquake sequence.
6. Capable of generating earthquakes.
9. A movement of surface material down a slope.
10. A sea wave of local or distant origin that results from large-scale seafloor displacements associated with large earthquakes.
11. The inner most part of the earth
12. The point on the earth's surface vertically above the focus, point in the crust where a seismic rupture begins.
17. The part of the earth's interior between the metallic outer core and the crust.