Ch. 15
Applying the Concepts

<See the back of the chapter.>

Questions for Thought

 1. 	The principle of uniformity is the frame of reference that the same geologic processes that change rocks seen today are the same processes that changed them in the past. It is based on the assumption that the laws of science are the same now as they were from the beginning. That Earth's history can be interpreted by tracing it backward from the present to the past. This tracing requires a frame of reference of slow, uniform change.

 2. 	Slow and deep: Folding
	Slow and shallow: Folding or faulting
	Quick: Faulting

 3. 	Faulting results from sudden stress on the cooler, more brittle rock near the surface. Folding from stress applied more slowly on deeper rock.

 4. 	At plate boundaries.

 5. 	The Pacific Northwest: subduction of Juan de Fuca plate.
	Alaska: subduction of Pacific plate.
	Hawaii: hot spot under the Pacific plate.

 1. T
 2. T
 3. F
 4. T
10. F
11. d
12. b
13. b
14. d
15. a
20. a
21. d