Answer to Question 1
Answer: You would expect structures that form under compression. Reverse (and thrust) faults would be forming at relatively shallow depths, where rocks are deforming in a brittle fashion. Folding of the rocks into anticlines and synclines would also be likely. I'd expect some variation on this diagram:
Answer to Question 2
Answer: Terranes are relatively small crustal fragments (microcontinents, volcanic island arcs, or oceanic plateaus). Terranes may be accreted to continents when subduction brings them to a trench, but they usually do not subduct due to their relatively low density. The terranes are peeled off the subducted slab and thrust onto the leading edge of the continent. Thus, they add bulk (mass, volume) to the edge of the continent. The western Cordillera is composed of many accreted terranes that originated mostly far to the south. Tectonic motions slathered them on to the edge of North America, and so their deformed, metamorphosed bulk piles up on the continent's leading edge like smashed bugs on the windshield of a fast-moving car.
