The
Teton Range is a small but dramatic mountain range of the Rocky Mountains, just south of Yellowstone National Park. The two principal summits are the Grand Teton at 13,772 ft and Mount Moran at 12,605 ft; most of the range is within the Grand Teton National Park. Along the fault line, the west block was pushed upwards to form the Teton Range, creating the youngest range of the Rocky Mountains... the east block fell downward to form the Jackson Hole Valley. On the southwest face of Mount Moran and on the Grand Teton magma has manifested as black dikes of diabase rock. Erosion and uplift have exposed the granite we can see today.