Description: From abstract: Numerous discontinuous layers of opal are interbedded with a gently-dipping series of vitric tuff and ash which is at least 300 feet thick. The tuff and ash are capped by a dark, vesicular basalt in the eastern part of the area and by a thin layer of terrace gravels in the area along the west side of Virgin Valley.
Date: May 1951
Creator: Staatz, Mortimer Hay & Bauer, Herman L., Jr.
Partner: UNT Libraries Government Documents Department