The upper Oligocene and lower Miocene Galiuro Volcanics in the northern part of the Galiuro Mountains contains two distinctive major ash-flow tuff sheets, the Holy Joe and Aravaipa MembersAsh-flow Tuffs Of The Galiuro Volcanics In The Northern Galiuro Mountains, Pinal County, Arizona: Usgs Professional Paper 1104 available on February 11 2017 from Indigo for 20.5
