 Erosion acting upon different types of uplift @-@ created joint and fracture systems is responsible for creating the valleys , canyons , domes , and other features we see today . These joints and fracture systems do not move , and are therefore not faults . Spacing between joints is controlled by the amount of silica in the granite and granodiorite rocks ; more silica tends to create a more resistant rock , resulting in larger spaces between joints and fractures . 
