[Trace Elements Program, Field and Colorado Plateau Projects, February 1948]

Two illustrations showing locations of Trace Elements Offices in the United States and an index map of part of the Colorado Plateau produced for a Febuary 1948 report of the U.S. Geological Survey's trace element investigations.
Date: 1948-03~
Creator: Geological Survey (U.S.). Trace Elements Office.
System: The UNT Digital Library