Changes to Earth's Surface

Across
4.	the upper part of the mantle below the lithosphere
6.	an instrument used to detect and record earthquakes
10.	the process of an oceanic plate colliding with and descending underneath a continental plate
12.	a deep valley that forms where plates move apart
14.	beneath the mantle; the layer of Earth in the center
15.	forms when molten rock is pushed to the surface and builds up
16.	the point on Earth's surface directly above the focus of an earthquake
17.	the thin outer layer of Earth
19.	the process of being broken down into smaller pieces

Down
1.	a plate boundary where the plates move together
2.	large ocean wave created by undersea earthquakes or volcanic eruptions
3.	the dropping or settling of eroded material
5.	the removal and transportation of weathered material
7.	the snap and slide of rocks as energy is released in Earth's crust
8.	the very thick layer of Earth beneath the crust
9.	a plate boundary where the plates are moving apart
11.	the crust and the upper solid part of the mantle
13.	the point inside Earth where an earthquake begins
18.	a break in Earth's crust where rocks can slide past each other