Terms : Hide Images
| 7991475615 | Plate tectonics | A theory explaining the structure of the earth's crust and many associated phenomena as resulting from the interaction of rigid lithospheric plates that move slowly over the underlying mantle | 0 | |
| 7991475617 | Subduction zone | A destructive plate margin where oceanic crust is being pushed down into the mantle beneath a second plate | 1 | |
| 7991475618 | Hot spot | An area where magma from deep within the mantle melts through the crust above it | 2 | |
| 7991475619 | Volcanic chain | Formed above a subduction zone | 3 | |
| 7991475620 | Mid-ocean ridge | An undersea mountain chain where new ocean floor is produced; a divergent plate boundary | 4 | |
| 7991475621 | Transform boundary | A plate boundary where two plates move past each other in opposite directions | 5 | |
| 7991475622 | Island accretion | When islands atop an oceanic plate are added on to continental crust as the two plates converge | 6 | |
| 7991475628 | Missoula floods | Massive floods that contributed to the formation of the Columbia Gorge, Willamette Valley, and Channeled Scablands. | 7 | |
| 7991475629 | Columbia Basalt Flows | Volcanic floods that blanketed much of the Pacific Northwest in basalt. | 8 | |
| 7991475630 | Date of Missoula Floods | Occurred at the end of the last ice age (20,000 - 10,000 years ago). | 9 | |
| 7991475631 | Cause of Missoula Floods | Failure of ice dam that extended from a glacier in Canada into Missoula Montana. | 10 | |
| 7991475632 | Erratics | Rocks carried away from their original resting places by glaciers. | 11 | |
| 7991475633 | Date of Columbia basalt flows | 17 million to 6 million years ago (Mostly around 15 million years ago) | 12 | |
| 7991475634 | Cause of the large earthquakes that periodically occur in the PNW | The Cascadia subduction zone | 13 | |
| 7991475635 | Cascade Mountains | Formed due to the subduction of the Juan De Fuca plate beneath the North American Plate | 14 | |
| 7991475636 | Yellowstone hot spot | Responsible for both the Columbia basalt flows and the Yellowstone caldera. | 15 |
