| Sunset Crater is a cinder cone that formed from a volcanic eruption in about 1064 to 1068 AD (Self, 1990). The cinder cone rises about 1000 feet above the plain in the Flagstaff area. Periodic eruptions continued for another 200 years. Sunset Crater is the youngest volcano in the San Francisco Volcanic Field. The San Francisco Volcanic Field has more than 600 hills and mountains of volcanic origin that have formed within the past six million years (Priest and others, 2001). The volcanic field extends from near the Grand Canyon rim south and east through the Flagstaff region. |
