Best viewed over the World Hillshade layer using the Multiply blend mode.

This layer combines the geologic investigations from nine 1:100,000 quadrangles. The source maps are:

Littlefield Quadrangle, 2001, by George H. Billingsley and Jeremiah B. Workman

Fredonia Quadrangle, 2008, by George H. Billingsley, Susan S. Priest, and Tracey J. Felger

Glen Canyon Dam Quadrangle, 2013, by George H. Billingsley and Susan S. Priest

Mount Trumbull Quadrangle, 2004, by George H. Billingsley and Jessica L. Wellmeyer

Grand Canyon Quadrangle, 2000, by George H. Billingsley

Tuba City Quadrangle, 2012, by George H. Billingsley, Philip W. Stoffer, and Susan S. Priest

Peach Springs Quadrangle, 2006, by George H. Billingsley, Debra L. Block, and Helen C. Dyer

Valle Quadrangle, 2006, by George H. Billingsley, Tracey J. Felger, and Susan S. Priest

Cameron Quadrangle, 2007, by George H. Billingsley, Susan S. Priest, and Tracey J. Felger

Source data were downloaded and converted into an ArcGIS Pro file geodatabase using the Personal Geodatabase to File Geodatabase Conversion tool and the ArcGIS Data Interoperability Quick Translator. The majority of the colors are based on the 1996 edition, originally published by the Museum of Northern Arizona (aka the "Dragon Map"). Missing geology types were copied from each of the other quads. A new field was created ("CartographicSymbol") and used to consolidate several types across the region and edge match (basalt flows and deposits, pyroclastic flows and deposits, some sedimentary and dune types).

This project was inspired by the work of Ryan Clark and his "Geologic map of the Grand Canyon and vicinity".