Chapter 2, Problem 10P

ǀ Plate tectonics. The earth’s crust is broken up into a series of more-or-less rigid plates that slide around due to motion of material in the mantle below. Although the speeds of these plates vary somewhat, they are typically about 5 cm/y. Assume that this rate remains constant over time. (a) If you and your neighbor live on opposite sides of a plate boundary at which one plate is moving northward at 5.0 cm/y with respect to the other plate, how far apart do your houses move in a century? (b) Los Angeles is presently 550 km south of San Francisco, but is on a plate moving northward relative to San Francisco. If the 5.0 cm/y velocity continues. how many years will it take before Los Angeles has moved up to San Francisco?