A blocky lava flow was erupted early in the history of this vent. The flow is 50 feet (15 m) thick near the cone. Near the terminus of the flow, about 4 miles (7 km) away, the flow is 180 feet (55 m) thick. Photo by Steve Mattox, 1989.
View north from Crater 160 to SP Mountain. SP Mountain it the dark cone left of center. Photo by Steve Mattox, 1989.

Aerial view looking north to SP Mountain. An older graben cuts across the top-left corner of the photo. Note two fingers
of the SP lava flows that spilled into the graben. Photograph by Wendell
Duffield, U.S. Geological Survey.
Ulrich, G.E., and others, Excursion 5A: Miocene to Holocene volcanism and tectonism of the southern Colorado Plateau, Arizona, in Chapin, C.E., and Zidek, J., eds., Field excursions to volcanic terranes in the western United States, Volume 1: Southern Rocky Mountain region: New Mexico Bureau of Mines & Mineral Resources, p. 1-41.
Ulrich, G.E., 1987, SP Mountain cinder cone and lava flow, northern Arizona, in Beus, S.S., ed., Centennial Field Guide Volume 2 Rocky Mountain Section of the Geological Society of America, p. 385-388.
Wood, C.A., and Kienle, J., 1993, Volcanoes of North America: Cambridge University Press, New York, 354 p.
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