Holocene scoria cone and lava flows at Sunset Crater, northern Arizona

Abstract Sunset Crater, about 15 mi (25 km) north of Flagstaff, Arizona (Fig. 1), is in the eastern part of the San Francisco volcanic field, on the southern margin of the Colorado Plateau. Access to the Sunset Crater National Monument is by Forest Road 545, an all-weather road off of U.S. 89. Included within the boundaries of the monument are the scoria cone of Sunset Crater and most of one of its associated lava flows, the Bonito flow. Another lava flow associated with Sunset Crater, the Kana-a flow, occurs in the Coconino National Forest east of the monument. Hiking is prohibited on Sunset Crater scoria cone, and collection of specimens is not permitted within the boundaries of the national monument. Topographic maps published by the U.S. Geological Survey that cover the monument and surrounding area are the Sunset Crater East, Sunset Crater West, O’Leary Peak, and Strawberry Crater quadrangles of the 7%-minute series. The geology of the area is shown by Moore and Wolfe (1976).