Silver Creek caldera - source of the Peach Spring Tuff

AZGS geologist Charles Ferguson and colleagues have a new paper coming out in Geology on the recently discovered Silver Creek caldera as the source of the Peach Springs Tuff.  [Right, Peach Springs Tuff in Silver Creek caldera.  Tamara Carley with Charles Ferguson (in cowboy hat). Credit, Calvin Miller, Vanderbilt Univ.]

Excerpts from the abstract (published online in advance of the print publication) conclude that "the Silver Creek caldera, which straddles the eastern edge of the Colorado River extensional corridor near Oatman, Arizona, is the source of the Peach Spring Tuff. A fragment of the caldera identified in the midst of the extensional corridor is structurally juxtaposed with mesozonal plutons of identical age. The implied extension direction (182°–225°) is compatible with abundant previously published structural data for the region." 

Ref: Charles A. Ferguson, William C. McIntosh, and Calvin F. Miller, "Silver Creek caldera—The tectonically dismembered source of the Peach Spring Tuff," Geology, first published on October 19, 2012, doi:10.1130/G33551.1