Geologic map of the central Gila Bend Mountains, west-central Arizona [Fourth of July Butte, Gillespie, and Quail Spring Wash 7.5 min]

Map, Bedrock, Surficial, Areal, Structure, Stratigraphy, Mineralization, Locale, Signal Mountain volcanic rocks - Miocene, Dixie Mine volcanic rocks, volcanic rocks north of Agua Caliente fault, Fourth of July volcanic rocks - Oligocene(?) or Miocene(?),