Poston Butte is a small, late Miocene outcrop of basaltic rocks located several miles northwest of Florence Arizona. A nearby porphyry copper deposit is named after Poston Butte. The Arizona Geological Society's 'Field guide for a transect from Florence to Miami, Arizona' (1996), edited by Steve Richard provides an excellent description of the Poston Butte porphyry copper deposit authored by Cori Hoag. http://archives.arizonageologicalsoc.org/guidebooks/AGS_1996-04_Trans_Fl....
Photographer: Mike Conway
Photo Date: 2017