Description:
E.D. Wilson's 1937 Ph.D. Dissertation, Harvard University, MA. Dr. Wilson was a senior geologist at the Arizona Bureau of Mines for many years.
Rocks which have been classified as pre-Cambrian are very prominent in Arizona, as indicated by the State Geologic Map. The most complete sequences of so-called Archean and Algonkian types known in the Southwest crop out in the Grand Canyon. Formations of known or supposed pre-Cambrian age constitute about half of the visible rocks in the State's numerous widely distributed mountain ranges which are largely isolated from one another by basins underlain with Tertiary and Quaternary beds.
Arizona’s greatest exposures of pre-Cambrian sedimentary and volcanic rocks are in the central mountain ranges, within distances of 90 to 200 miles from the Grand Canyon. This central region has yielded approximately 1500,000,000 worth of copper, gold, silver, lead, and zinc, mainly from the Jerome pre-Cambrian deposit and partly from numerous Mesozoic or Tertiary veins in pre-Cambrian host rocks whose salient controlling structures appear largely to be heritages from pre-Cambrian events.