Just as islands mark locations of the Pacific Plate that were once over the hot spot, volcanic rocks on the North American Plate mark locations that were formerly over the hot spot. Ages of the volcanic rocks indicate when that location was over the hot spot. Examine the relationship between the age of volcanic rocks and distance from Yellowstone.

11. In what direction has the North American Plate moved over the hot spot under Yellowstone? Describe your reasoning.

  !   Use the ruler tool to measure the distance the North American Plate has moved since forming volcanic rocks over the hot spot. Use the distance to answer question 12 below.