This interbedded Oligo-Miocene sandstone and conglomerate shows how streams can deliver a mix of coarse and fine debris, depending on stream flow conditions. Hackberry Wash near Winkleman, Pinal County. Photo by Jon Spencer.
For Bill Dickinson's 2008 report, "Conglomerate Clast Counts in Oligocene-Miocene Strata North from the Catalina Core Complex to the Gila River Valley, Southeastern Arizona", http://repository.azgs.az.gov/uri_gin/azgs/dlio/394
