The Granite Gorge (annotated)
From time to time the Tonto trail will come out into the main canyon and to the very edge of the inner gorge, known as the Granite Gorge. The rock here is known as the Vishnu Schist, and is in places intruded by pink Zoroaster Granite. Above all of this lies a layer of sedimentary Tapeats Sandstone, followed by all of the other sedimentary layers above that.