AZGS’s newest Down-To-Earth booklet recounts the geology of Flagstaff and the history of the Rio de Flag, the river that runs through it. Part 1 is an overview of the regional geology and Part 2 includes trail guides. For more info and a link to download the guide, visit the AZGS website.
Written by volcanologist Dr. Richard F. Holm, Professor Emeritus at NAU, the illustrated 70-page text includes 16 maps and 42 photographs and illustrations. According to Holm, “This geology and trail guide is for anyone who likes to walk, be outdoors, and is interested in the geology in and around Flagstaff.”
Citation: Holm, R.F., 2019, Geology of Flagstaff and Geologic History of Rio de Flag, Northern Arizona with Trail Guides to Geology along Rio de Flag. Arizona Geological Survey Down-To-Earth #23, 70 pages.